Review for HDR Express (Review)
Friday, 25th March 2011, 16:09

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Photography is a passion of mine, I will ramble on a lot here, for which I apologise in advance. If you just want to get straight to the product, skip to the next page, I won't be upset. It's okay, really, I won't even know you did it.

Digital photography is a wonderful thing, not because it has allowed anyone to instantly see the pictures they've shot, reduced the cost of shooting them, and increased the proliferation of snappy snaps. Sure, those are all nice and all, plus it is great for many people who wish to record the various stages of their kids childhood, family breakdowns, and so on. But the fact remains, for 99% of the people who take pictures, 99% of the shots they take are dull and meaningless to anybody who doesn't know them.

Sounds harsh? Next time, take a good look at your favourite snaps of family or friends, and ask yourself truthfully the following question. If you didn't know the people in them, would you really honestly give a damn about that "great" photo? Is that shot of some building you went to see in Italy good because it reminds you of your trip there, or good simply because well done, you got it all into frame?

No, digital photography is a wonderful thing because it has allowed thousands upon thousands of dedicated amateur enthusiasts to really learn about the art, both technical and otherwise, of taking and making good photographs, without having to be rich, or making yourself poor. Before we had digital SLRs, if you just wanted to go beyond the basics of framing a shot, and actually learn much about depth of field, the right exposures for the right situations, appropriate shutter speeds, and so on, you'd be painstakingly writing down settings for every shot in a notebook, forking out about 30p every time you clicked the shutter.

Then you'd have to wait a few days, and have no control over the final prints, unless you could afford a load of expensive equipment and chemicals. If you could afford these, then a whole new world of possibilities would open up, but again learning all the techniques of developing and processing your pictures would eat a load more of your cash. And all of that is on top of learning what makes a good photograph.

But today, with the ever tumbling prices of digital SLR cameras, once you've bought one and a lens to go with it, most of the expense is behind you. With the high dynamic range that shooting in RAW allows you to play with, even the developing of images has been revolutionised by such commercial applications as Apple's Aperture and Adobe's Lightroom, and recent free offerings such as RawTherapee and BlueMarine. Now you can have the versatility of your own darkroom, without having to own a darkroom. Tweak colour balance, grain, sharpness, vignetting, all sorts of non-destructive alterations are at your disposal.

So what is HDR Photography?

The thing these applications don't do, at least for now, is offer you the ability to combine multiple photographs of different exposures into one. Why would you want to do this? Well anyone who has taken a picture in lighting conditions which are far from perfect will soon have realised the eye is much better than a camera at dealing with the differences between bright areas and dark ones. It does this for two reasons, the first being it can simply see more levels of difference than the camera sensor can manage, and the second more important reason, it utilises a dynamic system called the iris.

When you look into a dark area, the iris will open to let in more light, much like the aperture on your camera does. When you look at a bright area, it will close to reduce the light and improve the contrast. But because your brain sees what is effectively a live video stream, you don't always notice it even doing this, unless you walk out into bright sunshine from a dark room, or vice versa. A camera gets one single frame to capture as much detail as it can, and you have to decide what you want to capture, the detail in the highlights or that in the lowlights. Only in the most controlled and artificial lighting conditions can you set things up so it can accurately expose its sensor to everything.

The difference between the lightest and the darkest parts of a scene that a camera's sensor can detect, is called its dynamic range. Your eye has a wider dynamic range, and when combined by the fact that your iris allows more and less light in any time it fancies it, you can see in a very high dynamic range, far more than a camera can capture. This often leads to disappointment with some photographs, they just don't look how you remember seeing them.

Let's take a sunset as an example. To catch the wonderful colours in the clouds and the atmosphere, requires an exposure which renders everything that isn't the sky a black silhouette. Getting the exposure which shows the much darker land based world, results in a blown out detail free sky. You can't win! Well actually you can, using a technique that has been used by photographers ever since the film days. You take multiple pictures, one which covers the correct exposure for each feature you wish to see. Then later on, in the darkroom (digital or otherwise) you combine the two images into one.

Obviously this is the sort of thing that is much easier to do in Photoshop than a chemical filled darkroom, the latter would involve making a mask to cover one half of the image whilst you exposed the other, and then the opposite. Needless to say lining things up was difficult, time consuming and prone to errors, especially as at this stage of the process you can't even see anything on the photo paper you are exposing.

Now HDR photography is essentially this process, but automated and taken one stage further using a technique called tone mapping or local contrast control. The general idea is you take a range of shots at different exposures, load them into some software which then combines all the images into one single picture, with each pixel containing information that covers a much higher dynamic range.

Using clever maths, HDR software can go way beyond what was possible in film days, producing anything from a natural look which is close to what your brain remembers seeing, right through to extreme contrasty almost computer generated visions of neon loveliness. It all depends on your tastes, and sometimes what software you use. For instance, Adobe Photoshop CS includes the ability to create a HDR image from a number of others, including doing a half decent job of aligning handheld ones too. But the only look you can get with it, is the natural one, extreme tone mapping is right out here.

Over the last year or two I've tried a few options, some fast, some fiddly, none of them perfect. The latest one to catch my eye is from a company called Unified Colour, which offers a range of three HDR products, the entry level of which is HDR Express. Aimed at amateur photographers such as myself, it describes itself as nothing less than "the game-changer in HDR software." Quite a boast, let's see how it shapes up to the competition.

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