• A bike company selling the idea of a frame that’s so light you won’t feel its weight
• A company specialising in sports health food and drink who wish to emphasize that it’s the athlete who succeeds, not the equipment.

Technically it wasn’t easy to produce so it’s a perfect subject for one of my anatomies.

The Cyclist

The shot of the cyclist was taken in a studio environment against a white backdrop. I used white rather than a green to eliminate any colour spill onto the subject. She was shot on a real cycle (secured on a home bicycle trainer) so as to ensure that she was in the correct anatomical position, and I shot her from lots of different angles to give me greater flexibility when creating the composite.

Examples of the studio shots

The problem with this approach is that the cycle covers up various parts of her body, so I then had her cycle her legs in the air and hold invisible handles so that I’d have the body parts that I would need to create the final image. These extra images were taken from the same position as when she was on the bike to ensure that the lighting was the identical.

The extracted cyclist. The bike covers up lots of the body.

Shots taken without the bike so that I've have body parts available during retouching

I don’t think the model really understood what my final aim was, so she may have felt a little silly complying with my bizarre requests!

For the lighting I relied upon my faithful ProFoto AcuteB strobes for the key light, and an SB900 for the rim light. The two were set off together using the new Nikon version of the PocketWizard FlexTL radio triggers.

Note that the decision to use a rim light was chosen to give greater three dimensional modeling to the image. This was done at the expense of a more flawless composition since there wouldn’t really be both a main light and a rim light in a natural environment (there’s only one Sun). In my image of the tennis player I was very careful about using one light since I wanted to create the most convincing image possible. In contrast, this image of an invisible bike is clearly impossible to start with and so I allowed myself a little more creative license. Nevertheless, to the untrained eye the rim light isn’t a noticeable giveaway…

The road

With the cyclist images in the bag I then hunted down roads that would be suitable. I knew what sort of thing I was looking for so used a number of scouting methods to find it: Google Earthing the local area, asking my entourage and just generally keeping an eye out when out and about. Eventually this road appealed to me.

As with the cyclist image I took the road from various angles so that I’d have an image that matched up with the angle of the cyclist image that I’d ultimately choose.

The backdrop

The backdrop of the road image lacked impact, so I decided to replace it. I tried quite a few candidates, from hills to mountains, but the green hills you see in the final result look best. It’s actually a snapshot that I took way back in 2004 while on holiday in Cyprus, just as I was getting involved in digital photography! The position of the sun produces a convincing look (to the untrained eye) whilst still adding some nice drama.

Putting it all together

Creating the composition took about a day and a half. The cyclist photo had to be chosen, extracted and then composited with various body parts to remove the bike. I originally had a false start in that the image I’d chosen looked great with the cyclist on the bike, however it looked very strange with the bike removed.

Once a better image had been chosen a suitable road image was used to match the angle of the cyclist, and she was blended into the image. The backdrop complete the composition, and the color toning finished off the image.

How can a proud father put photos of his children on his blog while still servicing the thirst for knowledge that his readership demands? I figured that this dilemma was justification enough to buy Nikon’s gorgeous new 85mm f/1.4G lens and put it through its paces.

Used wide open – which is what this lens is for – the 85mm produces beautiful dreamy images with sumptuously creamy bokeh. On a full frame body its the perfect focal length for a wide variety of portrait work, and after a few shots it instantly became my favourite lens.

I wish I could add something more useful for you, but what more can I say? There are lots of technical sites that demonstrate how incredibly sharp this lens is, and how perfect the corners are, how great the colour rendition is, and how well built it is; that’s all great stuff. What’s really important for me though is that only a super-wide 85mm can give this unique look, and that’s why I bought it.

Here then are a couple of family snapshots taken with my new toy. For the technicians, you’ll may like to know that the lighting is provided by an off-camera SB900 bounced off a wall and an on-camera SB700. Quick and simple, but effective.

Clovis and mum. Melty heart and melt-away background.

Big sister. Three and a half, going on ten.

Then in September last year I switched to Nikon. The reasons for this had nothing to do with flash, however as a result of the switch I’ve spent a lot of time familiarising myself with the Nikon system. I thought it might interest some of you to understand how the systems vary from the point of view of someone who has (now) used both extensively.

First off let me state that I personally find that both systems give me good results in terms of TTL flash exposure – neither are perfect, and with both systems the use of flash exposure compensation under various lighting conditions will be a necessity, but I don’t find one system better than the other in this regard. Rather, it’s the differences in usage that are actually fairly significant, and this is what I’ll be discussing.

Ambiant vs. Flash control

One of the biggest differences concerns how the two systems give you control over the ambient vs. the flash exposure.

The Canon system completely separates the two exposures, such that any changes made using the exposure compensation dial will only alter the shutter speed/aperture combination – the flash exposure is not altered. To change the flash exposure the user must use the Flash Exposure Compensation (FEC) setting.

Nikon have taken another approach. The camera’s exposure compensation dial affects the whole image, so any changes made will affect both the “background” ambient and the flash exposure simultaneously. The FEC setting, on the other hand, will only affect the flash.

Bumping up or down the background exposure relative to the flash exposure is something that I do all the time. With Canon, the separation of these controls makes this very easy. With the Nikon system such a manipulation would possibly require a change to the global exposure (ambient light and flash) followed by a further change to the flash exposure to put it back where it was before.

I say “possibly” because personally I work with the camera in manual mode 95% of the time. In this case one can therefore continue to control the ambient exposure by adjusting the shutter speed and aperture, and then use either the FEC or standard exposure compensation to adjust the flash.

My opinion is that Canon’s approach is to be preferred, it’s simpler and less fiddly.

Remote TTL

Both Canon and Nikon systems provide the ability to control groups of remote off-camera flashes, both using TTL for the flash exposure or by offering the ability to adjust the manual power of the flashes from the camera position. There are however major differences in how this is handled by each system.

The Canon system provides for 3 groups of flashes. In TTL mode Groups A and B are intended to light the main subject, and group C is independent. The flash exposure of the A/B groups is calculated such that together they correctly expose for the subject, however the A:B ratio can be easily changed by the user, and the FEC can be used to affect the exposure of the combined A/B group. In manual mode each group must be controlled independently. It’s not possible to combine TTL and manual modes.

Nikon have taken a more flexible approach to remote flash control. There are 3 remote groups + the master flash, and each can be placed into either TTL or manual. The FEC (for TTL mode) or the power level (for manual mode) can be adjusted separately for each group (or the master flash).

In my opinion the Nikon SB900 master is considerably easier to use than the Canon 580EX – the rear control screen has been very well designed in this regard. I also love the flexibility of the Nikon approach, and the independent control over each group.

Although Nikon’s flexible system would allow me to light independent subjects using different TTL groups, this would be an incredibly rare thing for me to do. Rather, the different TTL groups will typically be pointing at the same subject from different directions, and in this far more common scenario I like the ability to quickly change the ratio of the lights. Canon’s system makes this trivially simple, where’s Nikon’s makes this a little harder than necessary since each group will have to be changed individually.

Clearly Nikon themselves have realised this too since the A:B ratio mode is now available on the new mid-range SB700. Unfortunately the SB700 doesn’t allow for a combination of manual and TTL groups, so where it gains is flexibility in one area it loses in the other.

Assuming that the replacement for the SB900 keeps its existing flexibility whilst also providing the new ratio mode of the SB700, Nikon will win the remote TTL game hands down.

FEC

The two systems handle flash exposure compensation very differently, and for Nikon’s pro-body users it’s a bit of a kick in the teeth.

Canon offers a FEC control on both the camera body and their external on-camera flash units. Any changes that you make using the external flash unit will override the camera’s own setting. When using multiple off camera flashes separated into difference groups, the FEC will affect the A and B groups simultaneously.

Nikon’s approach is to offer an independent FEC control for each remote group (and another for the master flash) that can be controlled via the master flash unit. The on-body FEC has a cumulative effect with the FEC values that have been set on the master flash.  This allows you to control the FEC of all the groups simultaneously via the camera body, and to adjust individual groups using the master flash unit. Note that it’s not possible to change the FEC globally for all groups using the master flash unit itself.

As a side effect of this approach, the Nikon system also benefits from a greater range of FEC. The flash offers ±3ev of compensation and the camera body offers -3ev to +1ev – since they are added together this in gives a theoretical range of -6ev to +4ev. With the camera in manual mode the global exposure compensation is also added to the mix, giving a total range of -11ev to +9ev. Obviously this can’t be achieved in practice.

If this were the situation for all Nikon bodies then Nikon’s approach would be the better one to my mind, however they’ve thrown a huge spanner into the works for pro-body users. Specifically, since there’s no on-camera flash on D3-series bodies, Nikon didn’t see fit to provide users with any on-camera flash exposure compensation. As a result of this decision, when working with the camera in a semi-automatic mode remote flash work becomes rather more complicated:

• It is not possible to adjust the flash compensation for ALL the remote flash groups simultaneously – each group has to be adjusted one at a time.

• Accessing the flash compensation on the flash is slower and more awkward than access via the camera body.

• D3-series users don’t benefit from the extended FEC range.

Note that there is a partial workaround for these issues, and that’s to place the camera into manual mode. In this situation the standard exposure compensation will continue to affect the flash exposure as explained above.

That said, the primary situation in which one uses TTL flash rather than manual flash is one in which the lighting conditions are changing – and in many of these situations the semi-automatic modes may also be useful for handling changes to the ambient exposure.

Rear curtain sync

There is one final detail that’s worthy of note: Nikon support rear curtain sync with their off camera flashes, whereas Canon don’t.

Conclusion

It’s hard to really say if one system is better than the other, but here are my personal conclusions after using both systems:

• The Nikon system is considerably more flexible in terms of remote flash control, and that’s a very good thing.
• The Nikon system is also far more user friendly.
• Canon’s ratio control of remote flashes provides for quicker control over the common case scenario. I hope that Nikon add this to their top-of-the range flash quickly.
• In semi-automatic camera modes, Canon’s separation of ambient and flash exposure is preferable. In manual mode there’s no difference, but I still find it clunky to adjust the flash exposure using the global exposure compensation.
• The lack of FEC on Nikon’s D3-series bodies is a significant oversight. Canon’s pro-bodies have on-body FEC.
• Nikon’s rear-curtain sync for remote flashes is a nice advantage.

Planning

A shoot like this requires access to a top athlete – both for the move itself¹ and the physique, so my first problem was to find one that was willing to participate. After searching the Internet for a while I discovered that one of France’s leading gymnasts – Yann Cucherat – trains just an hour away from me in Lyon, so I contacted him, pointed him to my work and asked if he’d be interested. He was kind enough to say yes.

Yann’s training schedule was very busy so my time with him was going to be short. My assistant and I made sure that we were well in advance for our photo session, and this allowed us to prepare and test the equipment before Yann’s arrival.

Lighting and troubles

With my flashes I wanted to achieve two things: to simulate sun light and to freeze the gymnast’s motion. This would normally be a simple task, nevertheless in practice lighting the shot proved to be problematic. The issues involved are certainly worth examining in detail. Let’s look at the constraints one by one…

Constraint 1 – flash was the only option

I needed control over the light – not only was the ambient light was flat and boring but I needed a hard light source to simulate the sun for the final composition. A flash was therefore essential.

Constraint 2 – overpower the ambient light

Despite its size the gymnasium was actually very well lit thanks to copious amounts of overhead lighting and a number of skylights that were allowing plenty of daylight into the room.

Since there were other gymnasts in training there was no possibility to turn off the center’s overhead lighting. To avoid the motion blur introduced by the ambient light falling onto the subject my flash would have to deliver enough light to completely overpower the ambient light.

Constraint 3 – shutter speed

In order to minimise the contribution of the ambient light (constraint 2) the use of a fast shutter speed is a move in the right direction, however I couldn’t go any faster than my camera’s sync speed – a measly 1/200th of a second for the Canon 5D Mk II. Fortunately I was using a PocketWizard MiniTT1 to fire my flashes, so this allowed me to fire slightly over the sync speed – 1/250th – using their incredible HyperSync feature.

Constraint 4 – lowest possible flash power to reduce flash duration

To freeze motion I would need a fast flash duration. The Profoto AcuteB flash packs that I use provide their fastest flash duration at lower power levels (by switching out the capacitors), therefore the lower the flash power the better my chances of freezing the gymnast.

Constraint 5 – the aperture

The choice of aperture was being pushed in all directions by a number of variables.

• To reduce the ambient light (constrain 2) I needed a small aperture.
• To reduce the flash power (constraint 4) I needed a big aperture.
• To produce a convincing composite image the aperture would need to be similar to that used in the background shot. For example it would be odd to have a very shallow depth of field on the gymnast and a pin sharp background.

I decided to compromise with f/5.6.

Constraint 6 – the ISO

The choice of ISO was being hustled by the same constraints as the aperture.

• To reduce the ambient (constraint 2) I needed to reduce the ISO.
• To reduce flash power (constraint 4) I needed to increase the ISO.

The ambient light was really very strong. Given my 1/250 sec at f/5.6 the ambient light at ISO 200 was still introducing motion blur. I decided to move to ISO 100.

The compromise

With the ISO, the aperture and the shutter speed all fixed, the only remaining variable in terms of exposure control was the flash power, and I needed to keep that at a minimum (constraint 4).

Prior to buying my portable studio flashes I spent a long time examining the options that were available to me, and I detailed the results on this blog. I stated the following:

“Another excellent starting point would be to buy 2 AcuteBs, one with the bi-tube (Twin) head. This set up offers a great deal of flexibility – the two heads are totally independant for complete control and less cable routing problems. When portability is paramount one pack is very light to carry about. When more power, quicker recycling times or shorter flash durations are needed then the two packs can be used to drive the Twin head.”

This is actually the route that I took. By using two AcuteB battery packs with one Twin head I was able to further reduce the flash duration for the amount of power that I would need.

The shot of Yann used for the composition.

Was it enough to freeze the gymnast? No!

Despite my best efforts there was still a touch of motion blur. It’s was mostly visible on the feet and legs which were having to move faster than the torso. The face was sharp though, and that was critical. All the variables had been exhausted. I had two choices – either to call it a day or to accept the motion blur as a creative effect in final image. I took the latter.

The right moment

The 5D’s frame rate is very limiting for this sort of work, so catching Yann at the right moment in time was a matter of good timing. Yann was great to work with – he managed to repeat the move enough times for me to get the shot I wanted.

Compositing

With the photo of the gymnast completed I entered into the final stage of the creation of this image – the post processing.

I had a photo from New York that lent itself perfectly to the concept that I had in my head, and so I used this for the background. I had positioned the flash so as to provide exactly the same angle of light as the sunlight in this photo – this is vitally important when creating compositions.

To extract Yann from the gymnasium I used Photoshop CS5′s new Refine Edge improvements. Adobe have really done a fantastic job with the refine edge tool now.

The effect of perspective on an object is governed uniquely by the distance of the object from the lens (focal length is irrelevant), so to create a convincing composition the gymnast was placed such that he appeared to be approximately the same distance from the viewer as he was from me when I actually took the photo. In a photo like this there’s a little leeway before the eye really starts to notice something strange going on, so I made him a touch large than he would probably have been in reality. Note that this is different from the tennis player composition in which the perspective effect was so strong that the positioning was critical.

Finally there was a fair amount of tonal work involved to make the two images feel like they were a single whole.

1. If anyone can tell me what this move is called I’d appreciate it!

Many photographic workshops are aimed at newcomers who seek basic guidance and support, covering entry-level subjects such as exposure, composition “rules” and simple post-processing techniques. My objective is different — to address the needs of intermediate and advanced shooters who wish to push themselves further and overcome any hurdles that are preventing their progression.

With this in mind I have chosen not to offer a rigid menu of predefined workshops. Instead, I will discuss your requirements with you in advance so that each workshop will be a unique experience designed to meet the specific needs of its participants. Nothing is fixed — the dates, course content, duration and even the location are all open to discussion (and guidance).

You can browse the list subject areas that I’m currently proposing on my workshops site. If you have other needs then please feel free to contact me.

To get the ball rolling I’ve decided to offer a 20% discount on the first five bookings for 2010.

I thought it might be interesting for some of you if I explain how this image of a tennis player diving for the ball was created, starting with the concept and working through to the the post-production.

Concept

Once the initial idea for the photo had been conceived (and having the idea is often the biggest challenge) the first step was to determine exactly how to achieve the result.  In this case I clearly couldn’t ask a model to dive onto a real tennis court (that’d hurt I would think…), so the only option left open to me was to produce a composite image.

As with all commercial-style shoots it’s important to pre-visualise the final image since this will guide the choice of location, the model, the clothing, etc. In the case of a composite image this pre-visualisation becomes absolutely critical; if the result is to be successful each of the individual images needs to be taken under similar conditions.  If the perspective of each subject isn’t consistent, the depth of field doesn’t match or the lighting is too different then the final result won’t be convincing.  It’s not feasible to undertake a project of this nature without having a good idea of what the final image will look like.

Planning

I knew that I wanted to use a wide angle lens with the tennis player close to the camera for a more dramatic perspective, and this implied a number of important considerations:

• I would need a very wide chroma key (“green screen”) backdrop.
• I would therefore need a fairly large studio.
• The perspective distortion would be strong, so it would be very important that the photo of the tennis court be taken at the same focal length as the photo of the player so that I could place the player at the correct distance into the image.

Unfortunately I didn’t have access to a green screen as wide as I needed, so I had to improvise.  I ordered a 1.2m x 15m roll of “Fadeless Art Paper”¹ so that I could stick it up on the wall using masking tape.  I didn’t expect this to be ideal (and I was right!) however I was prepared to spend a little more time in post-production to work around any problems.

Other than the backdrop issue there were many other things to think about – even a small scale shoot like this one needs careful planning.  Here’s an non-exhaustive list of the things that I needed to consider or remember to bring along:

• The date and time: the studio, the model and myself all needed to be available at the same time.
• The camera equipment: which lenses and strobes would I need to bring along? I have a very long equipment check list that I use when planning a shoot.
• The model’s comfort: food and drink (I made a quiche), access to toilets, a place to change, etc.  Also, in this case, a mattress to land on!
• Setting up: It’s the simple things that are easy to forget – masking tape, scissors and a step ladder for  putting up the backdrop for example.

The “Dive” Shoot

The "dive"

I planned to give myself an hour of set-up time before the talent arrived, however I was lucky enough to find a great model who wanted to be involved in the whole process.   She arrived early to help me unpack the car and prepare the equipment.  Without her help putting the backdrop in place would have been a horrendous experience – thanks Selma!

I’d bought 2 mattresses and a thick double duvet to use as a landing pad.  I positioned these at the angle that I wished to take the photo and moved them as far away from the “green screen” as I could.  The combination of a wide angle lens, a very wide subject (model horizontally out-stretched with a tennis racket) and close shooting distance meant that I couldn’t get as much separation as I’d have liked, so the green would inevitably “spill” onto the model and increase the post-processing time.  The main light also cast a shadow on the backdrop (although that isn’t too hard to handle later).

The lighting setup was fairly classic.  I used two monobloc flashes to light the backdrop as evenly as possible.  The main light was a Profoto AcuteB with the “New Zoom Reflector”, placed just left of camera and just high enough to put a catch light in the model’s eyes.  I planned to use another AcuteB as a fill light but it wasn’t necessary in the end (the white walls did that for me).  Rather than let it go unused I was able to use both power packs together for the main light (a dual tube Acute “Twin” head) allowing me to reduce the flash duration to better freeze the model in mid-air.  Finally, a Canon 580EX with a C.T.O. gel used as a kicker gave a slight separation.  All the flashes were set off simultaneously using PocketWizard radios.

After an hour’s set-up time we were ready to shoot.  Once again I was lucky to have been blessed with a great and enthusiastic model.  She took a 10 minute jog to get the sweat going a little, and then proceeded to take 70 (yes, seventy.) dives onto the landing pad.

My 5D MKII was tethered to my Macbook Pro, and the images were bought into Lightroom² so that she could see her body position and facial expressions.  This sort of direct feed back really helps to get the talent involved in the shoot, helping them to help you.

At the end of the shoot I took an image of a tennis ball under exactly the same lighting conditions.  This would facilitate the composition later on.

The “Tennis Court” Shoot

The tennis court

The choice of court would have an huge effect on the final image.  Since I wanted a slightly gritty/hard feel to the image I found a court that would suit that look.

The light falling onto the court was very flat – not at all like the hard light falling on the model – but that actually gave me more opportunity to control the image in post-production, and for the look I was after the flat light was more appropriate.  Had I wished for more lighting consistency it would have been crucial that the light was coming from the same direction as the light on the model (and that would have cast my shadow on the ground, complicating things a little).

The only major shooting considerations were therefore the focal length and aperture (which needed to be the same as that used in the studio), the focal point and the angle of view.

Post Production

I personally use Lightroom to catalogue and rate my images, so the very first step was to bring the images into my main catalogue. Once this was done I selected the images that would be used in the composite.

To choose my selects I use an iterative process.  On the first run through I give one star to all the images that have any possibility of being selected (in this case filtering out the ones where there model has already landed or where she wasn’t placed correctly in front of the green screen, etc).

I then filter for only these images and go through again to find the 2-star images – this is possible now that I have a familiarity with all the images in the collection.

In the third iteration I find the best images from the collection and I also check for critical focus.  If necessary a fourth iteration will leave me with just a few images to select from.  For this shoot the body position and facial expression were the two most important criteria.

Once I had my “dive” shot selected I bought it into Photoshop to remove the green screen (and the green spill).  This is a critical step, a badly cut out image will destroy the final effect.  Delivering a well-executed composite image requires a fair amount of post-processing experience and familiarity with your editing application (Photoshop in my case).

The tennis court also received some retouching to remove the fussy background. I wanted a clean image in which there weren’t lots of details fighting for the user’s attention.

The resulting composition is achieved using a fair number of layers in Photoshop.  Good use of layers ensures that the composition is created non-destructively so that it can be tweaked until it’s right.  The three principal images (court, talent and ball) are included as smart objects so that they can be transformed and retouched many times without compromising the image quality.

Here’s a look at the resulting layers palette to give you a feel for the work involved. Bear in mind that some of the work isn’t visible here since it’s inside the smart objects (the green-screen masking, for example).

Note that it’s best to read from the bottom up.

Attention to detail is essential if the composite is to look real to the casual observer. Things such as the subtle colouration of the ball and t-shirt from reflection of the ground help to ensure that the result is as seamless as possible.

Over to you…

I hope that this has been a useful insight into a shoot of this type.   There are many things to consider and to control, but this is what makes photography so interesting!

If you’re interested in learning more about photo realistic composition then you may be interested in the workshop that I’m going to to start offering for 2010.

If you have any questions then please feel free to leave a comment so that others may benefit.

1. This was harder than it should have been since I couldn’t find such a thing in France so I had to order from the UK.
2. Tethered shooting is possible using a combination of EOS Utility and Lightroom

To this end, over the course of the last few weeks I’ve been doing a lot of research into the various options that are on the market. Unfortunately I couldn’t find any resources on-line that grouped all facts together to help make the decision easier, so I’m sharing the fruits of my labour in the hope that it’ll serve other photographers.

Updates

I shall continue to update this post retrospectively to fix any errors or to add new information that I deem pertinant.

History

28 May 2009: Added importance of minimim flash duration to the discussion.
26 May 2009: Added flash duration for Acute Twin head, and discuss the use of two AcuteBs as a great starting setup.

The Contenders

There are battery powered flash systems available from all the major flash manufacturers, including Profoto, Elinchrom, Hensel, Bowens, Bron, White Lightning and Alien Bees. However, since Paul Buff’s White Lightning and Alien Bee systems are not readily available in Europe I eliminated them from my research. I also eliminated Bron since they’re far too expensive. That left Profoto, Hensel, Bowens and Elinchrom.

Criteria

In the comparison that follows I’ve compared the specifications of the various options available.

When considering a flash system some of the most important factors, price aside, are the power, flash duration, recycle time and the weight of the system, so I’m going to take a quick detour to discuss these points. The one thing that I don’t talk much about in this article is price – each photographer will have their own budget to consider.

Power

How much power should a portable flash have? This is a key question to answer when choosing a system because it’s going to have a direct consequence on the weight, and therefore the portability of the battery pack.

Questions to ask include:

Will you be shooting at the brightest time of day?
Will you need to overpower the ambient light, or are you just wishing to supply fill?
Will you be using a softbox or a reflector? Softboxes will require more light.
Will you be shooting in confined spaces or with wide apertures; will you need to turn the power right down?

To overpower sunlight using a softbox at 2pm in the afternoon on a bright day, you’ll need power, and you should definitely be looking at a system offering 1000Ws or higher. Most people consider 600Ws to be borderline for overpowering the ambient light, but depending on your shooting style this may not be an issue, in which case the 600Ws units are more portable and less expensive.

A good alternative would be to invest in a 600Ws system that offers a bi-tube flash head. When you need 1200Ws (or a shorter flash duration) you can put two packs together. When you don’t, you have more flexibility in the placement of the packs, and the ability to travel with half the weight when only one light’s needed.

Having lots of power isn’t necessarily a good thing however. Often the more powerful flashes don’t have a power range that allows them to be fired a very low power. The Bowens Explorer 1500 is such an example – it offers 1500Ws, but can’t be fired at less than 31Ws. When working with wide apertures or in circumstances where the light can’t be moved further back, the minimum power level can quickly become a real problem. I often stumble into this when using my 600Ws Bowens Geminis in the studio – their 6 stop range is limiting on the lower end. The problem can of course be address using ND filters, but it’s a pain.

Flash duration

If you need to freeze action then a short flash duration is absolutely essential. The manufacturers typically quote the ‘t0.5′ value for the flash duration, which is the total time that the flash output is above 50% of its maximum for a given power level. To equate the flash output to an equivalent shutter speed (for freezing action) we really need the t0.1 value (the total time that the flash output is above 10% of its maximum), and we can fairly reliably calculate this by multiplying the t0.5 value by 3.

For example, a t0.5 flash duration of 1/3000s is approximately equivalent to using a shutter speed of 1/1000s as far as freezing action is concerned.

The duration of the flash is dependant on the power level chosen. It is generally quoted that, in the case of portable strobes such as these, the shortest flash duration is achieved at the lowest power level, and the longest at the higher power level. This being the case, overpowering the sun (high power requirement) and stopping action (low power requirement) may be mutually exclusive.

During my research however, it’s become clear that not all the power packs behave in accordance with this rule. In effect, as the various capacitors are switched in and out to achieve the desired power level, this has an effect on the flash duration that’s difficult to predict. For example, the Bowens Explorer 1500 has its shortest duration at 1000Ws, and the Hensel Porty 12 at 300Ws. Also of note is that on asymmetric packs the shortest flash duration will normally come from the lower powered output.

Unfortunately this level of detail isn’t readily available. I’d be happy to add flash duration curves to this article if my readers can provide the raw data.

Recycle time

This is simply the time that it takes for the strobe to recharge ready for the next shot. Clearly, it’ll take longer to recharge when shooting at full power than it will at low power.

If your shooting style is fairly slow then this will probably have little bearing on your final decision, however if you’re shooting action it can be the most important criteria when choosing a pack.

Weight

The weight of the pack may well be very important for you. If you working alone and moving about a lot then a low weight system will have a huge advantage. A small flash pack that you can put into a backpack is a lovely thing to have.

On the other hand, if you’re doing large commercial shoots and have assistants and transportation at hand then the advantages of the larger packs will probably outweigh the weight disadvantage.

For this reason, many photographers may eventually choose to go both ways and buy different pack for different uses, and this foresight may well influence the buying process:

• Does the manufacturer offer both heavy and lightweight systems?
• Are both these systems appropriate for you?
• Are the modifiers compatible with both systems?
• Are the heads compatible with both systems? Is that important to you?

Facts and Figures

I shall start with a direct comparison of the fact and figures since they’re easy to compare. They don’t tell the whole story however, so I will follow with a more subjective comparison afterwards.

To make this comparison fairer, I’ve divided the various product lines into two groups – those of less than 1000Ws, and those of 1000Ws or more. If we don’t do this then many of the figures become meaningless; for example the Hensel Porty 6′s stunning 1s recycle time is very impressive when compared to the Elinchrom Ranger’s 3 seconds – but of course it only has to reach half the power…

Packs offering 1000Ws and higher

Packs offering less than 1000Ws

Other considerations

If there were one flash system that stood out as the clear leader then that would certainly make the buying decision a lot easier. Unfortunately this isn’t the case. Each product range has its advantages and disadvantages, and there’s always a compromise to be made.

Aside from the compromises that can be seen from the above tables (power vs weight vs performance) there are other things to consider too. Here I’ll look at each system and add my own subjective viewpoint.

Bowens

The Bowens Explorer 1500 battery pack offers excellent value for money, and may well be the best compromise for a number of people. The Bowens system itself is very extensive and their innovative “Wafer” softboxes are considered by many to be the best of any brand.

Pros

• Very short flash duration (1/5700 at 1000Ws)
• Very reasonably priced
• Highest power output available (1500Ws)
• Full asymmetry – both heads can be controlled independently.
• A total of 4 heads may be attached – 2 QuadX’s and 2 Gemini Esprit monoblocs

Cons

• Noisy fan
• Slow recycle time
• A friend of mine who uses this system tells me that RF noise it emits interferes with (US) Pocket Wizard reliability. Need to use Pulsars instead.
• No lightweight portable system alternative (TravelPak requires Gemini monoblocs)
• No option to remotely control the power levels
• Minimum power level is high (31ws), which may be annoying when working at wide apertures

Elinchrom

Elinchrom offers what is arguably the best overall system in terms of interoperability. The Rangers offer good performance with a much lower weight penalty than either Profoto or Bowens and at a reasonable price. The Quadra’s compliment the Rangers very nicely when portability is essential, and the Ranger heads can be used on the Quadra. Furthermore, the Elinchrom modifiers are plentiful and very well regarded.

That all said, most users appear to strongly dislike the mounting system, describing it as fiddly and error prone. There are plenty of stories of softboxes falling off because they weren’t attached properly! Also, the Elinchrom range stops short – when the Rangers don’t have the recycle time that you need, there’s no top-end product to turn to.

Pros

• Excellent all-round system
• Good choice of modifiers
• Reasonably short flash duration
• Light weight
• Skyport system allows for remote power adjustments
• Battery change is quick and efficient – very well thought out
• Weather resistant thanks to sealed push button interface

Cons

• Build quality often considered lower than the alternative – may be a little more fragile
• Slow recycle times
• Very fiddly mounting system
• Digital interface less convivial than analogue knobs (personal opinion)
• No very high-end portable offerings

Hensel

The new Hensel Porty stands apart from its peers due to its Lithium battery technology. Using Lithium rather than Sealed Lead Acid gives the Porty some major advantages in weight and recharge times.

If portability is the most important feature for your shooting style then the Hensel will be a great tool. The Porty 6 out performs the competition easily. However, if you’ll eventually need more performance then there are no options in the range that’ll match the Profoto B2, so this could be limiting.

Pros

• Very low weight
• Very quick recharge time
• Very fast recycle times
• Excellent flash duration for the Porty 6
• Hensel radio system allows for remote power adjustments
• Weather resistant thanks to sealed push button interface

Cons

• Mediocre flash duration for the Porty 12 – especially when looking at the other advantages. A real shame that they couldn’t do better here.
• Digital interface less convivial than analogue knobs (personal opinion)
• Uninspiring range of modifiers
• Less common, so harder to find accessories etc.
• Spare batteries are very expensive

Profoto

When reading forums and talking with other professionals Profoto stands out as the brand of choice. Profoto products are expensive compared to the other brands, but they’re renowned for their build, reliability and superb light quality.

All is not rosy however. As a complete system I feel that Profoto is somewhat behind its peers. The AcuteB offers great portability, but the autonomy is poor and the recycle times and flash durations are very poor compared to the Hensel Porty 6. They’re also limited to just one head, and that head isn’t comptable with the other products such as the B2 or 7b, so if budget is tight it’s going to be hard to build up a system gradually. Finally, none of the battery packs are currently compatible with Profoto’s “Air”‘ system for remote power adjustment.

Do they have any redeeming features? Yes, of course. In terms of raw performance the B2 is the absolute best in class with the fastest recycling time and the shortest flash duration, although the price one pays for this is the weight. Moreover, they have what is undeniably the best mounting system. It’s quick and easy to use, and it allows for the reflectors to be “zoomed”. By moving a reflector back and forth the spread and quality of the light changes, giving the creative professional a wealth of possibilities that simply don’t exist with the other brands. It’s possible to change the fall-off of light in a way that would be very difficult in any other way.

All this is very infuriating. With Profoto you get both the best of what’s on offer (performance, build, superb mount) and the worst (price, system limitations, no remote power control) in one package, and you have to pay the highest premium for it.

If budget isn’t an issue then all things considered, Profoto is an excellent choice because it’s the system that has the most room for expansion (e.g. when you need more speed, there’s a pack that offers it). If you have the means to buy into both head systems then the system disadvange goes away. However if budget is an issue then think carefully before investing.

A single B2 is a great place to start, but the 7b represents awful value for money, offering very mediocre flash durations and recycle times.

Another excellent starting point would be to buy 2 AcuteBs, one with the bi-tube (Twin) head. This set up offers a great deal of flexibility – the two heads are totally independant for complete control and less cable routing problems. When portability is paramount one pack is very light to carry about. When more power, quicker recycling times or shorter flash durations are needed then the two packs can be used to drive the Twin head.

Pros

• B2 offers best in class performance
• Very high build quality
• Easy to rent
• Best mounting system by far (can aslo accept adapted Elinchrom modifiers)
• Excellent range of modifiers

Cons

• Expensive
• B2/7b packs are very, very heavy
• No radio system for remote power adjustments
• Not at all weather resistant – care needs to be taken.
• The AcuteB is poorly spec’d compared to competition equivalents
• B2 is best in class, but also heaviest
• Acute and Pro heads aren’t interchangable

Conclusion

All the systems that I’ve looked at have their own advantages and disadvantages. There’s no one brand that stands out as the obvious choice, and each photographer will have his or her own specific needs. It’s an unfortunate reality that it’s very unlikely that any of the systems available today will meet all of them. For example, I’d ideally like a small, light weight, 1200Ws pack that offers a very short flash duration and an extremely fast recycle time. In practice I can have all of those things, but not in the same package.

Given the sums of money involved I feel that it’s very important to take time to examine the various offerings and to make an informed decision based on your own requirements. Many forum discussion include comments along the lines that the light quality is essentially the same from all of them, and that all the systems will do a great job. Such commentry may be true for the person stating his or her opinion, but don’t be so blindly led. You may be very happy with your Elinchrom Ranger until the day that the 3s recycle time drives you mad and there’s no better option to upgrade to. You may love your Profoto until you realise that you need another light and you can’t afford it. Hensel offer a great package – but can you get parts easily where you live?

My advice is simple: consider not just what you want to do with the flash now, but also what you’ll do with it in the future. Look at the whole system, be very aware of the compromises that you have to accept, then decide.

Neil Van Niekerk has just written a very interesting comparison between Canon and Nikon flash systems.  Neil’s a very experienced TTL flash user, and uses both Nikon and Canon extensively, so there’s really no better person to discuss the subject.

His conclusion is that for on camera TTL (including bounced flash) the systems are just different.  That’s all.

We often hear that Nikon’s flash system is better than Canon’s and being the curious fellow that I am I’ve tried many times in the past to get to the bottom of this question by searching the net.  Until now I’ve never seen a decent comparison – probably due to the fact that there are so few people who are intimately acquainted with both systems.

I personally use Canon’s ETTL-II flash extensively, and I’ve never had an issue with it. It’s always worked extremely well for me. Clearly understanding the system is key to getting good results in either case.

However, I was very interested to note Niel’s thoughts concerning the better ease of use of Nikon’s off-camera TTL, so I took a peek at the SB-900 manual…

Here’s my own feature comparison based purely on reading the Nikon manual, my own experience with Canon, and the things that are important to my own use of flash.

Initial impressions

I certainly like the way that the SB-900 presents the information to the photographer, and I also like the way that the system allows the photographer to have total control over each flash group independently (for example, placing one group in TTL and another in manual). It seems easy to understand, and certainly slightly easier to grasp for someone new to off-camera TTL flash than Canon’s user interface.

Full TTL

In a full TTL situation the two systems are very different.  With Nikon you control the flash exposure compensation of each flash group independently whereas with Canon you control the overall flash exposure and then the ratio between the A/B groups. Nikon’s approach is easy to understand.  If Canon has an advantage here it’s that its very quick to change the ratio (and thus the output of two groups at once) with the simple turn of a dial – and this is something that I do all the time.  It seems to me that the Nikon flash system would require me to alter each group in turn to achieve the same thing which may be less efficient.

In practice however I assume that both systems simply require the photographer to adapt.  Like for Niel’s conclusions regarding on-camera TTL, I think that the systems are simply different – not really better or worse. In this case they’re so different that I can imagine that frequently switching between them would require an uncomfortable amount of mental gymnastics. However for those of us that use one system all the time I don’t think that there’s really an advantage to either approach. They both have their advantages and disadvantages, and they’re both so advanced as to excel in the right hands.

Mixed TTL/Manual

Where Nikon’s approach shines is in its flexibility. The ability to mix manual flash groups with TTL groups at will is extremely nice.

The most common usage scenario for this would be to use manual flash to light a stationary background object, and TTL for the moving subject.  With Canon the nearest we can get is to use group C for the background. This group fires under ETTL independently of the A:B ratio, however since it’s ETTL it may change slightly between shots.

Nikon wins here.

Full Manual

The final scenario is that of full manual flash control of all groups via the master, and in this respect the two systems offer the same level of control, so there’s no winner.

Other differences

There are a couple of other small things that swing in Nikon’s favour.   The most obvious one is the ability to use the pop-up flash as a commander.  The second one is that the on-camera flash is in a group of its own (under Canon’s system it belongs to group A) thus there are four groups rather than just three; nevertheless I’m not sure how useful that is in practise.

Conclusion

Nikon’s flash system is perhaps a little more flexible for advanced users, however both systems are so well refined that the difference shouldn’t be blown out of proportion.

As for the all important flash exposure calculation, I’ve never had any issues with Canon – and I note that Neil didn’t bring up and issues either….

So, I thought I’d take advantage of the unusual situation to create this image that I’ve had in my mind over the last few weeks.   I started by taking the photos of the chocolate sauce.  The consistency needed to be just right to get the look I was hoping for, and I was thrilled with the results.  I’ve put a couple of the resulting shots here to show you the results.

The photos were taken against a white wall which was lit just enough to overexpose it.  There was a softbox to the left of the poured chocolate and a reflector to the right, and these are responsible for the lovely long highlights on each side.  The twists were just the results of good luck.

I created an intial composition using three of the resulting images and then worked from there.  We had a box of particularly tasty chocolates so I took images of some of those (note that unlike the chocolate sauce we didn’t have too many of these).  I was careful to use the same lighting setup as above so that they would fit naturally into my composition.

The little round sweets were thrown by hand into the air and captured in mid-flight.

Finally I set forth upon the chocolate powder.  This was a lot harder to get right.  I tried all sorts of things to capture the powder in mid air but nothing worked well.  Eventually I decided to take a close-up shot of the powder on white paper using a Canon 135mm and some extension tubes.

Once I had all the elements I put them together using Photoshop to create the composition above.

1. Use a wide aperture

I love the look that shallow depth of field gives, and to that end I have a collection of wide primes. Most of the photos that my friend picked out were taken with a wide aperture to separate the subject from the background and to give that indescribable dreamy look that comes with it.

This image was taken with my 135mm at f/2.

My suggestion to him was to buy a 50mm f/1.8 prime lens and to use it lots. Both Canon and Nikon versions of this lens are great because:

I use flash a lot, and the ability to control my remote flashes from my camera is very important. The latest annoucement from the RadioPopper team now has me on the edge of my seat.

Background info

Both Canon and Nikon flash systems have the wonderful ability of allowing the photographer to control up to three groups of remote flashes directly from the master flash on the camera. When working in ETTL mode (for automatic flash control) the systems both work the same way:

1. The photographer presses the shutter button.
2. The camera fires each group in turn in order to measure the baseline flash exposure of each group independantly.
3. The camera calculates the appropriate power output of each group based on the photographer’s choice of settings and the baseline flash exposure just measured.
4. The camera sends each group the actual power level to fire at.
5. The shutter is released and the camera tells all the flashes to fire.

How does the camera communicate with the off-camera flashes? It uses flash! The master flash on the camera sends a coded sequence of very fast flashes that the receiving flashes can understand. All this happens so fast that all we see is one single flash at the moment we press the shutter release.

The technology also offers a major advantage to manual flash shooters in that the power level of each group can be controlled directly from the master flash so there’s no need to keep walking back and forwards to get the flash levels sorted.

The Problem

The technology is very impressive but it has a major disadvantage – the remote flashes have to be able to “see” the main flash, otherwise they can’t receive the coded signals that are sent by the controller. If you want to hide a flash round a corner, for example, you need to find another way of firing it; using radio is the obvious solution.

Radio?

The ability to fire flashes using radio isn’t new, there are many systems on the market at every price point imaginable. The world leader in the professional circuit is PocketWizard, known for their extreme reliability and long firing range. However these systems are only able to fire manual flashes. When they detect the flash signal they tell all the receivers to fire the remote flashes, but they aren’t able to send the coded sequences necessary for controlling the Canon and Nikon flash systems.

Another major drawback to this approach is that these triggers can’t be used to fire a Canon or Nikon flash in high speed mode when the photographer needs to fire above the maximum sync speed.

The Solution

In 2007 my dream of radio controlling my Canon flashes saw a glimmer of light. The RadioPopper was announced. An ingenious system that would attach to a master flash unit and watch for flashes. It was then capable of sending the coded sequence via radio to the receiver units that would literally replay the flashes to the slave flash. The project was very ambitious, but it would ultimately prove to work incredible well – it can even fire remote flashes in high speed mode.

Choosing between PocketWizards and RadioPoppers was not an obvious choice. RadioPoppers would fire my Canon flashes in ETTL mode which would be fantastic, however PocketWizards could be used to fire my Studio strobes and they had a much longer range. Ultimately though I decided that RadioPoppers would be the right choice for me.

The great news for me at the time is was that the first units were to be available in the US at the beginning of 2008 and they would then ship to Europe just three months later! I put my plan to equipe myself with PocketWizards on hold¹ and prepared for the wait.

The Great Depression

Unfortunately things were not to be. The first RadioPoppers available in the states were several months late, and the European version has never seen the light of day due to a technical design issue that has apparently resulted in a neverending round of paperwork.

The Saving Grace (I hope)

However, all is not lost. The latest news from RadioPopper has given me a new glint of hope. The team has learnt a lot from their first design and has now announced a redesigned system with some great new features. The firing range has been expanded to over 500m, the units are smaller and better designed, there are 16 channels to choose from and the transmitter can now also fire both manual flashes and ETTL flashes at the same time (in the same picture). This means that I can now easily use my Canon flashes alongside my Bowens in the studio. With this version the choice between PocketWizard and RadioPopper is obvious – RadioPopper wins hands down for my use.

And the best news of all is that the new version should be available in Europe within just 6 weeks of the US release.

I’m waiting with baited breath. It’s been a very long wait, but it looks like it’ll have been worth it.

1. Actually I bought two so that I could fire my camera remotely

Each region of France has its own specialities to offer, a tradition that brings water to this photographer’s mouth just thinking about it…

A village a few kilometers from here, Chabeuil, is known for its Caillette, a sort of ball of pork based paté (I daren’t ask more) that’s served warm with bread and salad. Believe me, it’s delicious…

Anyway, I digress. The point of this post is that Chabeuil holds an annual Caillette Fair where the different farms get to show off their Caillette making prowess, and each year the local camera club is asked to put on a small exhibition of pig photos (as you do). For a bit of fun I thought I’d offer my services.

I asked a friend of mine to assist and we drove to the local mountains to visit a free-range pig farm. The farmer thought we were bonkers, but he was nevertheless happy to let us “endulge our desires”, so we put our wellies on and set to work.

Also, I hadn’t appreciated just how big pigs could be. It turns out that up until this moment I’d only ever seen small pigs. Pigs can be much bigger than I’d ever imagined!

Even long range shots were hard; the pig that I was shooting may have been a fair distance away, but there would always be one of his friends wanting to say hello.

My “assistant” had her own problems to deal with. The ambiant light was flat so I wanted to add a little kick using off-camera flash. I’d given her a 580EX flash attached to an umbrella and a Pocket Wizard to set it off remotely, and her job was to get the umbrella as close to the subject as possible, from varying angles, as I was trying to take photos. Have you every tried to get a big white umbrella next to a pig without them noticing?

One of the best pieces of lighting advice I’ve ever heard is that to create an interesting image, one shouldn’t light all of it.

During the exhibition I constantly overheard amused parents explaining to their children that this is what they meant when they chastise them for eating like pigs!

Here’s a couple more, to see you out the door. (I’m a poet!).

I keep hearing this phrase at the moment, and it drives me nuts. There are many times when natural light is just great, but refusing to use flash at all is senseless on many counts.

Firstly, natural light is very often either flat and uninspiring or too contrasty and uncontrollable; this limits the times that a photographer can take beautifully lit photographs. There’s a reason that landscape photographers return to the same spot night after night for that perfect photo; they’re waiting for the perfect light. Beach-based fashion shoots are done underneath a giant diffuser to reduce the contrast to a manageable level.

Secondly, there’s often no natural light to use. When we’re inside the light comes from man-made light sources; should one not take photos under these extreme conditions? In fact, the above utterance that started this article often comes from someone who really means to say ambient light, rather than natural light, which is scary because those overhead fluorescent tubes are going to completely flood the room with overhead light, resulting in terrible flat photos of green people with dark eye sockets. “But hey, didn’t need flash!”

Finally, not liking flash is senseless because light from a flash is light like any other. A flash photographer can choose to recreate the type of lighting that most people think of when they say “natural light”, which is soft directional light with a warm colour tinge. Alternatively a flash photographer can decide not to use a flash because the natural light is just perfect, or do both by using the ambient light alongside flash to get the best of both worlds. A flash photographer can have beautiful light just about anywhere (landscapes apart!).

I can’t think of any valid reason to treat flash with distain.

Before I go on, here are four images to ponder over:

One is taken under natural light only
One is taken using flash alone
One is principally lit with natural light with flash used to lift the shadows
One is principally lit with flash with natural light playing it’s own role

Can you determine which is which? You can click to see bigger images.

l’ll give you the answers in a minute, but first let’s talk a little about light.

Light

Beautiful lighting is achieved through beautiful light, wherever it comes from. There are four important things to bear in mind:

1. The direction of the light.
2. The quality of the light.
3. The contrast of the light.
4. The colour temperature of the light.

The direction of the light

The direction of the light will determine where the shadows lie, and it’s the shadows that’ll model the subject, telling the viewer about the object’s form and three dimensionality.

The quality of the light

When we talk about the quality of the light we’re really talking about the size of the light source relative to the subject.

If the light source is much bigger than the subject then the light will wrap around them and soften the shadows – ideal for a child’s face, for example. This is known as soft light.

If the light source is small the shadows will be strongly defined and will emphasise the texture in subject – perfect for that sumptuous chocolate pudding. This is known as hard light.

In the home the most beautiful natural light images are often taken when the subject is asked to move next to a window. Why? Because it’ll result in soft, directional lighting.

The contrast of the light

The contrast in the image is very important as it will set the mood. However, too much constrast can also be hard to work with – We’ve all seen photos of a silhoutted person in front of a stunning sunset…

Hmm, maybe a flash could help there?

The colour temperature of the light

Light isn’t all white. Candle light is orange, sunsets are a more yellow, a fluorescent tube gives off green light, and tungsten is blue. This colouration is known as the colour temperature of the light. Flashes have a colour temperature that’s very close to daylight.

The colour of the light can also set the mood of the photo. Evening light often has that indiscernible tinge that can even make the most ugly of mankind’s monstrosities look beautiful. David X Tejada masters this fact, as witnessed by his industrial photography.

Putting it all together

Each of these aspects of light is of utmost importance, and it’s surprisingly rare that the natural light conditions are ideal. The reason that the evening light is the most appealing is because it is often directional and warm in colour. On the other hand taking well lit photos under the midday sun or on a grey overcast day is often much more challenging.

With flash the photographer has control over all of these aspects. The direction of the light can be chosen by moving the flash. The quality of the light is controlled using softboxes, umbrellas, or simply by bouncing the flash off a nearby wall or ceiling. The contrast is controlled by adjusting the power of the flash, and the colour temperature can be controlled with filters.

Mastering flash gives you creating lighting possibility when natural light can’t. Why deny yourself?

Answers

OK, I won’t keep you in suspense any longer.

The 100% flash image is that of the iron artist, taken with an off-camera flash camera left (shot through an umbrella) with on-camera fill to reduce the shadows.

The 100% natural light image is that of the restaurant. Are you surprised that there’s not more contrast between the back of the room and the window lit table? It’s actually a blend of several photos each with a different exposure; a subject for another blog article…

The back light in the photo of my baby daughter Annouk is a veiled window, Annouk herself is lit by flash bounced off my living room wall so as to create a soft directional light. This was probably the easiest image to get right since the window was a big clue.

Finally, the image of the ceramist is mainly natural window light with flash used to fill the shadow areas.

Conclusion

If you didn’t get the above answers right and you’re one of those people who “don’t like the look of flash” then you need to take another look at your stance. When used correctly flash can create beautiful images.

If you’re not using flash then you should seriously consider it – it’ll open up your photographic world. Reading the Strobist website is a good place to start.