Lighting and Colour Adjustment 101

Despite the efforts of Glenn Pure and others to improve the image processing skills of members, I continue to be disappointed by the poor lighting and colour adjustment of images posted to our galleries including in the advanced level competition. Many members seem to be unaware of the most basic tools and appear to make these adjustments by ‘eye’. This is most unwise because there is a wide variation in the quality and state of calibration of monitors. Even with a well-calibrated monitor it is difficult to judge by eye whether a particular colour channel is saturated. This can only be done quantitatively and in this series of posts I will show examples of how to check the lighting and colour adjustment using simple tools.

The subject I have chosen to illustrate these notes is an Eastern Yellow Robin where care needs to be taken to prevent the yellow breast from saturating in the red channel. The first example is a screen shot snipped from the Canon DPP4 RAW conversion and adjustment editor. The values of the RGB numbers from any pixel in the image can be viewed in the top right area under the colour channel histograms. By moving the cursor around the image one can quickly find the brightest pixels which in this case are on the bird’s yellow breast. I have then used the brightness slider to raise the overall image brightness (+0.67 stops) so that a few pixels on the breast are saturated with R = 255 DN. This is all that is required. Notice that this is a quantitative adjustment and does not rely on having a good ‘eye’. All RAW conversion and adjustment software have some basic tools to make this kind of adjustment.

In subsequent posts I will show how one can view the lighting and colour adjustment in Photoshop to check that the steps used to finish the image have not caused adverse colour channel saturation.

Thank you Ian for helping me unravel the mysteries of DPP4 ? I will be following your tutorials with great interest

Hi Ian,
Thanks must go out toGlenn and 'Others' for their consistent and persistent efforts in the past to help us all learn a decent, well thought out workflow.
Saying that, I too, will be reading and applying your techniques into my own workflow.
My only problem at this stage is that I am heavily in debt to a Lightroom system that I still haven't even scratched the surface of what's available and probably never will.
I have persisted with this system only because of the outlay involved but it might be time to sever all ties and start following a similar path to yours but with Nikon's software?

One question that I do have for you is the time within your workflow when you adjust your colors and lighting? Is it before or after initial noise removal or after?
Kindest regards,
Bruce

Hi Doug,

There are no 'mysteries of DPP4', it is the simplest and best RAW conversion and adjustment workflow for Canon photographers that I know. My notes on how to effectively use DPP4 have been privately circulated to quite a few members and were updated at the time of the Geelong conference. At that time and subsequently, Rob Parker intimated to me that the notes would be published on the BLP website for easy access by members but for reasons I do not understand, this does not seem to have happened. I am now trying a little piecemeal approach using the Forum but because it is piecemeal it opens up questions like the one from Bruce which would not have arisen if he had my full set of notes showing the workflow priority.

Kind regards, Ian

Hi Bruce,

Lighting and colour adjustment is one of the top priorities in any RAW processing workflow. It should be done before noise reduction but you may not be aware of this as there is a hierachy of adjustments that will be prioritized in the background when the RAW conversion takes place. RAW conversion and adjustment software like Canon DPP4 has a logical workflow based on the layout of adjustment windows and buttons within the windows. One just follows the trail from left to right and top to bottom to achieve the optimum workflow. After RAW conversion you will have a 16-bit TIFF file for finishing in, for example, Photoshop. This provides another opportunity for noise reduction if you are unhappy with the result achieved by the RAW conversion software.

Hope this helps, Ian

Hi Ian,
Thanks for your help mate. I have downloaded the Nikon NX-D software and the user manual and as usual, Nikon has chosen to use any other language except that being used by everyone else and at the moment I'm going through the manual to correlate the manual with your teachings. It seems as if they do the same operations but certainly not in the same order as you or Canon.
Hopefully it will be the beginning of a long and happy partnership? That reminds me, I must give Warren a ring and have a talk to him about his workflow with the NX-D software.
With Post Processing being such a huge part of photography now, it puzzles me as to why Birdlife Photography didn't publish your articles in the first place?
Thanks again Ian,
Bruce