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I took part yesterday in a London Photowalk hosted by Daniel Davies.
It’s the first time I’ve done a photowalk and the reason I took part in this one was because of an interesting format for the walk.

Rather than walking about snapping photos, there were the following restrictions:
1) We were allowed a maximum of 36 exposures during the walk
2) We set the ISO at the beginning and it couldn’t be changed.
3) The display on the back of the camera was taped over so we didn’t know how we were doing

What made this interesting is that we’re taking the principles of film photography and applying it to the modern technology. By giving us these self imposed restrictions makes us really slow down and really think about our composition before taking the shot.

I knew it would be an adjustment (the last time I shot film was in college), and it was a bit more of an adjustment than I expected. I’m not one to waste shots as it is, but by restricting the exposures to 36 and hiding the display really emphasised this.

At the end of the 2 hour walk I was well under the 36 allowed shots, so I rushed the last few … and it shows.
I took 33 alltogether and we sat in the pub at Tower Bridge (we started at London Bridge) with hot drinks to thaw our frozen fingers while we reviewed the shots on a laptop.

If you’re interested in seeing my pictures, then click on either the top image or one of the images below

HDR Single Exposure

This is a follow-on to my previous post HDR Explained

To recap – HDR is a method of blending images to get as much detail as possible from multiple exposures.
In this post I’ll (hopefully) explain why it’s best to avoid it if possible and show you an example of why you don’t really need HDR.

So ….. you’ve taken a picture of a landscape and created an HDR composite.
You like it.
Your family and friends like it.
You share it on Flickr and a bunch of sheep say that HDR is rubbish and false and rubbish (x2 so it must be true). Probably because they heard a friend or an ‘internet Pro’ dissing it.

The fact is that people can’t say someone is wrong when it comes to a personal opinion or personal taste.
If you like it then you like it, if you don’t then you don’t – there is no right or wrong. But nobody should tell you not to do it just because they don’t like it.

So, do I use HDR?
…. er… no

I know I just did the big "in defence" thing, but the reality is that, unless you’re a landscape photographer (which I’m not) then in most cases HDR isn’t really practical. It’s a possibility when you have a static subject, but when you want a dynamic image and you’re photographing something like racing or sports or doing portraits then it’s really a no-go.

So to still make your images "pop" then you need to start digging into the areas of lighting and/or more advanced post-processing.
This means you actually have to do some work instead of pressing 2 buttons and letting your computer do the heavy lifting for you 😉

At this point you probably want me to show an example so …..

Here’s an example image which I took waaaay back in March this year.
You will see that the image has almost bleached the sky and yet under the car is still soooper dark.

I take the Raw file from the camera and enter it into Lightroom. From here I’ll start making some non-destructive adjustments to the file to the point that it looks something like the file below.

As you’ll see, I’ve recovered a lot of the details back into the image and it now has a better balance. At this point I’d normally export it for a client to see as part of their online gallery/contact sheet so they can make their selections.

Normally this would be 95% there, but cars can usually take quite a hard edit, so from Lightroom I’ll export the image as a 16bit TIFF (for maximum detail) into Photoshop.
In PS I’ll start running through some actions that I’ve built with an aim to get to the image I have in my head. In the example below – this took me a little while to do which is why I’ll only do it on client selected images, not all of them.

This to my eye is the way it should look with perhaps some final polish to finish it off.
Part of my editing involves "painting" in the detail and dynamic elements to the image, whereas with HDR it’s like pouring a bucket over the picture and what you get is what you get.

Generally speaking HDR looks quite flat because the contrast has been eliminated during the blend, but it also tends to look "soft" too. You’ll see the processed single image is 100% pin sharp and has depth and form created by the contrast.

So, by taking the time to build some PS experience I can create something I’m happy with.

So there you have it. HDR Vs Single image editing. No composites or pulling elements from other pictures. It’s enough to catch someone’s eye and if you look deeper you can see it’s edited, but not enough to make it too detailed and flat the way HDR does.

For more examples of single exposure editing – see my earlier post on Colonsay Panoramas. Some of those were stitched together from up to 19 images to create 1 huge panorama which was then edited once in photoshop. I shudder to think of doing those in HDR (PC meltdown).

Click the split images to see a direct before and after:

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If so then drop a note below 🙂

For those that don’t know what HDR is …. its an acronym for High Dynamic Range and it’s a method of blending multiple images together to create a single image composed of the detailed elements of all the images.

Why do it?
The main reason is to do with limitations of a camera sensor/film Vs the human eye.
If you were to look into shaded woodland with the sun overhead then the human eye can almost cope with the extreme bright and extreme dark that’s visible …. almost.

Ansel Adams created a zone system which segments the extreme Low and High tones.
The human eye (amazing thing that it is) can see a huge range of zones, most film can see about 4/5 of the range at a time and 35mm digital cameras about 3/4 (although they’re getting better every year). But the bigger the sensor chip, the bigger the range of tones captured.

11 stop zone chart from Imroy at wikipedia
00
01
02
03
04
05
06
07
08
09
10

Because the camera sensor is limited, when you take a picture of a subject which is an extreme zone you can "bracket" your exposure over multiple shots and pull all the data from each one to create the single image with the composite detail from the darks to the lights.

You can do the composite in-camera, but more often than not people use software which’ll do an HDR composite for you in a minute or two.
Most commonly Photoshop and Photomatix.

Good right? Not quite 😉

  • The good is that if you don’t have time or experience in editing then you can pull together an interesting image quickly and with little effort.
  • It also can create surreal images which are more like paintings than pictures, although some photographers tend to look down their nose at those

But there are downsides.

  • You have no control over the final result. Ok, you can adjust the intensity of the tonemapping, but it’s applied to the whole image
  • If you have any noise…. any at all in the image, then the HDR process will multiply it and it can look pretty bad (esp. in extreme tone mapping)
  • You have to take up to 9 exposures to get 1 final image which eats into storage space.
  • If you move the camera, even a fraction, between shots then chances are it won’t work.
  • It’s ok for 1 static subject, but a nightmare if you want to do a panorama, stop motion sequence etc…
  • If anything moves in your shots (trees, water, politicians, skateboarders…. :)) then they’ll repeat as ghosts – ruining the final image

So …. do I use it?
Yes and No. I rarely do HDR as I’ve developed a workflow that means I don’t need it, but that’s not to say I won’t do it if I’m in a pinch …..

The closest I get in reality when in extreme conditions is to take a 5 stop bracket (-2 to +2) and when I’m editing I’ll choose the best one of the 5 to edit rather than doing an HDR composite.

I’ll explain how to create a dynamic image with a single exposure in my next post. More to come…. 🙂

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If so then drop a note below 🙂

For those that don’t know what maximum flash sync speed is, put a flash on your camera, in Speed or Manual mode set it to 1/400s and take a shot. You’ll see that half the frame (usually the bottom) is darker than the top.

This is where the shutter is passing the sensor too fast for the flash and it closes during the flash fire.

Up until recently, the only cameras that were capable of high-speed sync were Medium Format digital cameras (e.g. Hasselblad) that cost £10+K. Medium Format cameras have a different shutter system (usually in the lens) and so the sensor is exposed to the image in a different way.

In the older film days, 35mm cameras had a maximum sync speed of about 1/60s …. which was a bit naff.
It’s only until fairly recently the maximum you could achieve with increased to 1/250s with Nikon and 1/200s with Canon.

Although this was much improved over the old systems, it was still limiting to what you could do in broad daylight.

Then Nikon brought out what they call “Auto FP High-Speed Sync” and Canon call “High Speed Sync”.

This allows the camera to fire a speedlight multiple times as the shutter curtain passes the sensor which ‘paints’ the images onto the sensor at much faster shutter speeds.
It basically makes the flash last a bit longer so that it gets all the image lit right to the bottom

The cost for this is a bit of power.

Where your flash may be outputting F22 @1m at full power, if you increase the shutter to, say, 1/2000, you’re Aperture will need to drop to a lower value (F8?) to maintain the same exposure.

This in itself is amazing and the fact that modern strobes like the SB800 and SB900 (and Canon EX580?) can cope with this is phenomenal and opens up a lot more possibilities with your photography. It kills the batteries, but that’s why we keep spares handy ;)

However, there are 2 drawbacks to this.
1) The camera has to be able to communicate to the flash to do this. Either in the hotshoe, using a remote hotshoe cable, or with some cameras, with the built in flash can talk to the speedlights
2) As mentioned above, there’s a power loss when increasing the sync speed beyond the native 1/250 sync as the flash has to increase it’s duration

So to increase the power you need more powerful lights than your speedlight, but you can’t make Studio Strobes sync faster than 1/250s ….. or can you ?

The answer is Yes.
Better than that, there’s 3 ways of doing it :)

The expensive way to do it is to use a PocketWizard MiniTT1 and FlexTT5 triggers to do this. But at approximately £225 each, its not cheap.
It will let you sync up to approx 1/500s (so I’m told) which is better, but not quite in the 1/5000s area.

In a light controlled area (e.g. a studio) use the flash to set the shutterspeed, not the camera.
The flash duration of a studio strobe varies on the make/model, but in all cases the duration is shorter(faster) at the lower power output than at full power. e.g the flash duration of an Elinchrom Ranger head can reach up to 1/6000s

This is the duration of the light emitted from the flash and in a light-tight room will be the only light source, so anything photographed will be at the flash’s duration speed rather then the one set in-camera.

To set up a high-speed shot, black out a room and set your camera to the correct ISO and f/stop for the power set on the srobes.
Set a long camera exposure (e.g. 2-20 seconds) and take a test shot with no flash.
If there’s any hint of an image then there’s ambient light from somewhere. Find it – block it.
To do the live shot you must manually trigger the strobes during the exposure …. and there you have it, high-speed sync.

The on-location way to do it is to use your existing speedlight (SB800 or SB900) to blip the light and set your studio strobe to be optically slaved and it will fire with the speedlight, but giving much more power than the speedlight could dream of.

The downside of this is that the flash needs to reach the Studio head which should be fine up to a point, but if you have remote lights beyond range or around corners, then the PocketWizards will be required

Below is a pictorial example of how to achieve High Speed Sync with just 1 speedlight and studio flashes.
NOTE: The studio lights are set to their lowest power setting throughout and my Nikon D700 is set to AutoFP on

1st shot – ambient light

Ambient. 1/13 @ f/7.1 @ ISO6400

I hook up an Elinchrom Skyport trigger as the BXRi has a built in receiver.

Ambient. 1/40 @ f/3.2 @ ISO6400

Pow!!! These things kick out some light…

Wireless Skyport. 1/200 @ f/8 @ ISO400

Switch off the Skyport and set the camera to a ‘flash’ setting and take a shot to show that no ambient is showing

Ambient. 1/250 @ f/11 @ ISO400

Switch the Skyport back on and … Half decent exposure. Notice the bottom edge of the frame is a bit dark. Looks like the Skyport/Elinchrom combination is not quite 1/250s which is a surprise. 1/200s will be fine though

Wireless Skyport. 1/250 @ f/11 @ ISO200

Increase the shutter speed to 1/400 and there’s the typical sign that we’ve exceeded the sync speed

Wireless Skyport. 1/400 @ f/11 @ ISO200

So lets try a PC Sync cable to see if that’s better

Ambient. 1/40 @ f/2.8 @ ISO6400

Looks fine at 1/200s. Let’s up it to 1/250s to see if we get the dark area at the base of the frame again

Sync Cable. 1/200 @ f/11 @ ISO200

….. Nope – it looks fine. The wire connection is fine at 1/250s. The wireless must be a bit sluggish

Sync Cable. 1/250 @ f/11 @ ISO200

Bump it to 1/400s and there’s the clipping of the frame again. Interesting that it’s much lower than using the Wireless trigger due to the immediacy of the hard wire connection

Sync Cable. 1/400 @ f/11 @ ISO200

Time to try the speedlight. Ignore the settings in this picture
It was actually set to [TTL][BL][FP] for the next shots

Ambient. 1/160 @ f/2.8 @ ISO6400

Ambient shot at much lower settings. The speedlights pack a much lower punch so need to adjust down accordingly

Ambient. 1/200 @ f/2.8 @ ISO400

Flash switched on and ….. not too bad

SB900 TTL FP. 1/200 @ f/4 @ ISO200

1/250s is showing clean edge to edge illumination

SB900 TTL FP. 1/250 @ f/4 @ ISO200

Ramped it up to 1/800 and it’s still lit fine, but notice the slight warmer colour shift

SB900 TTL FP. 1/800 @ f/4 @ ISO200

Ramp it up to 1/4000s and it’s still popping away quite happily

SB900 TTL FP. 1/4000 @ f/4 @ ISO200

I now set the SB900 to manual and it’s lowest setting (1/128) as per the picture 6 up from here. It actually shows [M] [FP] to indicate that it’s in high-speed-sync mode.
The Flash hardly does anything to the image, but will easily trigger the BXRi optical slave….

SB900 M FP 1/128 power. D700 1/4000 @ f/4 @ ISO200

Set the optical slave on and ….. hey presto. Clean image at 1/250s

SB900 M FP 1/128 power. D700 1/250 @ f/11 @ ISO200

Bump it up to 1/800 and, although it’s darker in the top of the frame, the bottom section is lit.

SB900 M FP 1/128 power. D700 1/800 @ f/11 @ ISO200

Increase to 1/2000s and it’s still lighting it. Bare n mind this is the BXRi at minimum powerand the camera settings are 2 stops darker than when using the AutoFP with the SB900

SB900 M FP 1/128 power. D700 1/2000 @ f/11 @ ISO200

Increase the F stop to F4 rather than power up the strobe head

SB900 M FP 1/128 power. D700 1/2000 @ f/4 @ ISO200

Hardly any change when increasing it to 1/4000s

SB900 M FP 1/128 power. D700 1/4000 @ f/4 @ ISO200

And again virtually no change even though the camera is firing at 1/8000s
…. yes 1/8000s sync with a studio light :)

SB900 M FP 1/128 power. D700 1/8000 @ f/4 @ ISO400

So there you have it. The easy way to perform maximum sync speeds on your camera and still be able to use studio lighting to light your subject.
Any comments, please add them below 🙂

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