September 14, 2011
Post-production of digital images on a computer has something of a bad reputation. Many people think that it is time-consuming, difficult and somehow cheating. Yet post-production of images is an integral part of digital imaging. It can involve subtle changes or significant edits, but rather than thinking of these as something alien to the whole process, it’s worth thinking of post-production in the same way that film photographers used to think about printing their pictures in the darkroom: a chance to take something good and make it better.
Many people dismiss this as image manipulation and think of it as cheating, but I like to use the term correction: using post-production to compensate for the deficiencies of the photographic process and sometimes of your own photographic technique. This might be a picture with too little contrast, a slight colour cast or even a stray object in the frame.
That being said, many people do take post-processing a lot further. Sometimes this strays into the realm of digital art, but often it can produce a result that is crass and obviously fake. Where you draw the line is largely down to your own preferences: I aim for reality – even if reality needs a little helping hand.
Often there will be something in the frame that you really don’t like. This might be an old cigarette packet in a landscape, an elbow sticking into the picture or a straying tourist in a red Kagool! If it’s something that plainly doesn’t belong, then I will consider removing it. My criteria is essentially honesty: if someone were to revist the location of my picture, would they see the object I have just removed? So I will remove annoying people and litter, but leave in telegraph poles, scaffolding and mobile phone masts – no matter how much they might affect the picture.
Retouching is quite simple: even relatively simple software should have some sort of clone feature where you can use one part of a picture to paint over another part of the picture. Don’t be too ambitious though – removing a footprint from sand is quite easy to do without it looking obvious. Taking one person out of a crowd demands far greater skill if it is not going to look obvious.
One of the most dramatic changes that you can make for your photography is to switch from shooting with lower quality JPEGs to the high quality RAW format. This is essentially a digital negative that needs to be post-processed before it can be used. Some more sophisticated compact cameras and all DSLRs will be able to shoot RAW. It takes up more space, but it is much higher quality.
You can alter the white balance of a RAW file on a computer without any loss of quality. RAW is also optimised for a variety of tonal corrections that will help you to bring the most out of your pictures – increasing low contrast pictures, or lightening deep shadows that are obscuring details.
You can still apply some of these corrections to a JPEG, but this tends to be less easy – especially when correcting significant white balances – and in general you will get a higher quality result working with a RAW file.
The first stage of post-processing is editing your pictures. This is not just a case of throwing away the pictures that don’t work, it can be a great way to learn what you are doing with your pictures. All digital images contain a lot of information in their metadata. You can see the lens, exposure and even ISO used. As you’re editing, look for patterns. If you see a bunch of pictures with camera shake, check what shutter speed you were using: this will give you an idea of how good you are at handholding for a given lens, and what speed you should aim not to go below next time. This is also a good time to decide how high an ISO sensitivity you are comfortable with before the noise is too great.
Always check the focus by zooming to 100% when choosing between two pictures – otherwise you might keep a slightly out of focus shot over one that is pin sharp.
Once I have my final folder of ‘keepers’ I automatically give each one a unique number, so I will never accidentally copy it over another picture.
Previously, I have looked at backing up your pictures on the road; you also need to make sure to back-up pictures when you get back home. I maintain three copies of every shot. These are saved on hard drives. This is the cheapest way, and is much less hassle than trying to burn endless DVDs. One of my three copies is stored in a firesafe, although if you work away from home you can store one at work, or even at a friend’s house to avoid having everything in one place.
Work out a good back-up routine where you have one master disc and a back-up, to avoid copying pictures the wrong way and over-writing new work with old.
It is also worth considering some sort of cloud storage: a service like Flickr will give you unlimited storage for a relatively small amount a year.
Next time, we will look at some of the of the techniques you can use to post process RAW files and JPEGs to achieve a more polished result.