I took this shot handheld at 1/20 with a 50mm prime lens, with the ISO set to 800. The actual shot in raw form is quite under-exposed, but at ISO 800 if I tried to boost the exposure all I would do is add too much noise. So I used a technique that’s very useful for night shots, or anything where you can’t get a long enough exposure without a tripod – and I’m not attracting attention to myself by setting up a tripod in the middle of the main drag in Preston.
First I took a copy of the layer, and did a Black and White conversion, and set the blend mode to Overlay, this dulls the saturation somewhat, but the main effect is to increase contrast. The resulting image was far too dark, so keeping the monochrome version at the top of the layer pile, I added copy layers which I set to Screen mode. Each one increases the brightness, but without any knock on effect on noise levels. Sometimes one layer is enough, and I tweak the opacity until I get the right effect. Sometimes, as in this case it takes more than one layer – this one ended up with six screen layers. This begins to saturate the colours, and the result has deep dark blacks and rich colours. It’s an effect that could be overdone, but I like how it’s worked in this example.