Colour is often the key factor in underwater photographs. A keen photographic eye and a few fine adjustments in postproduction can improve colours and give your image the final touch.
The fine-tuning of our underwater images in postproduction requires a closer look at colours and a skilled photographic eye. Just aimlessly sliding sliders in Photoshop or Lightroom software and seeing what happens rarely results in pleasing images.
The ideal starting point is to have an image in RAW or DNG format, a calibrated computer screen, proper lighting in your workspace and image-editing software such as Adobe Photoshop or Lightroom. Ninety-five percent of image editing can be done in Adobe Camera Raw (ACR)—the RAW processor of Photoshop—or in Lightroom, which offers the same functions but has a user interface that looks a bit more fancy.
How you want your image to look after editing is your choice alone. It is your photograph and you can do with it whatever you want. But let’s see how we can improve images with just a few basic steps!
The very first step in solving colour problems is always the white balance. I adjusted the white balance in the example shown (see Image 1) and applied a few subtle exposure and contrast adjustments (see the inserted screenshot from ACR). After that, the image now looks like Image 2.
The photo generally looks ok. There are lots of colourful subjects in it, and the histogram looks fine. But I believe that more can be done with it regarding the colour.
On first impression, the easiest tools to use seem to be the Vibrance and Saturation sliders, found in ACR and in Lightroom’s development module. However, with these controls in particular, a lot can be done wrong, especially when overusing them.
Vibrance boosts the saturation of your lower-saturated colours. This might sound nice, but let’s have a closer look.
While a slight boost of +20 to the right brings slight improvements (see Image 2), a value of +50 results in unnatural colours (see Image 3) and “full-power” at +100 almost destroys the image (see Image 4).
Let’s look at the extreme version of +100 vibrance boost in Image 4. We might think, “Wow, that really pops!” But actually, a lot of the colour details are wrong. In simple terms: it’s too much of everything (I hope you agree with me).
Now, our next try involves saturation. Saturation increases or decreases colour intensity across all channels. Let’s have a look at Image 5.
It is the same story here: A subtle move to the right indeed adds a little helpful saturation to the image but when overusing it (+50 or even +100), things go nasty. Let’s check the “+100” boost in Image 7.
What appears as “colourful” in this image actually consists of mercilessly oversaturated colours.
Conclusion: I would use the Vibrance and Saturation sliders extremely carefully, or even better, not touch them at all. The thing is, we do not want to “boost” all the colours in an image; we want to do subtle adjustments to specific colours that we find could use a little help in postproduction. This means that we first need to see and understand what to fix by focussing carefully on all the colours in the photo. And secondly, we need to use a precise tool to work on those specific colours. By the way, this is the last call for calibrating your computer screen (which should be done before moving on to the next step).
Let’s have a closer look at the tutorial image and mark a few colour areas that could use improvement (Image 8).
- Zone 1: The orange colour of those fishes is pretty poor and flat.
- Zone 2: The red and purple tones of this soft coral are slightly washed out.
- Zone 3: The colours of this hard coral look flat.
- Zone 4: All the blue tones of the water look a little flat.
As always, in proper postproduction, it is crucial to zoom in to 100% and then scroll and look around in the image to spot the finest details or “problem zones.”
As we are still working in the RAW processor, the most powerful tool to use to work on fine adjustments of specific colours (in ACR and Lightroom alike) is the HSL control tab.
You access the HSL control tab by clicking on the fourth icon in the top menu bar of the ACR window (left). In Lightroom, it is in the development module, just below the tone curve control.
HSL stands for Hue, Saturation and Luminance, and the HSL tool provides the option to modify hue, saturation and luminance of ANY colour in our photos.
- H (Hue): A gradation or variety of a colour
- S (Saturation): The degree of chroma or purity of a colour
- L (Luminance): The quality or condition of radiating or reflecting light
We can now optimise or alter specific colours in the image by moving the single colour sliders of the colours we want to edit (this means that if there is no problem with the reds, there is no need to play with the red slider). This counts for each colour and for each state (hue, saturation and luminance).
Back to the tutorial image: After focussing mostly on the orange, yellow, red and blue tones and altering their hue, saturation and luminance values, the photo now looks like Image 9.
The orange-coloured anthias are now in nice contrast and harmony with the blue water—and those soft and hard corals are looking fancier now as well.
Please bear in mind that all editing steps in Photoshop ACR or Lightroom are non-destructive, thus providing the welcome option to alter specific editing steps or (in some cases) just go back to zero and start again from scratch. ■