Thanks Ian. RawTherapee seems to do quite a lot of things well, its just a pity it is so user-unfriendly. i have often thought that if the developers could add a simplified interface with a limited range of adjusters covering the basics it would be a much better option.

How does white balance work with the colour checking process? I presume your playing field test would have been done using normal daylight colour temperature settings (is it 5600K, I can’t remember?). Can we assume that Neutral remains accurate with other colour temperatures provided WB is accurately set?

Simon

I recently came across this free PDF download on the internet. Members reviewing or setting up their own Colour Management workflow may find this a valuable reference, as I did

“Colour Management for Photographers” by Mark Galer

Free download (PDF) available from https://assets.adobe.com/public/0932b7d6-1cbb-4a6b-4ab1-f0dd484f6bf1

This free 54 page eBook is written primarily for Adobe Lightroom / Photoshop users, but should also be relevant to users of other software. It does assume some basic understanding of Lightroom and walks the reader through the definitions, usage and setup of a full colour management system for both web and print applications.
Topics include:
Benefits of colour management
Colour Science
Camera Profiles
Monitor Profile
What happens when we don’t colour manage
Key terminology
Colour Space
Choosing RGB working space
Out-of-Gamut Colours
Implementing a colour managed workflow
Profile your camera
Choose a monitor
Set colour profiles in Photoshop
Choose your preferences in Lightroom
Profile your monitor
Optimize your monitor
Soft Proofing
Output
Rendering Intents
CMYK

This is my first response to the forum as I have just found it. Some of you may know of me from your responses and realise just how much I don’t know. In respect to color, shading and all other like issues I can only respond for my self. Previously I have never used any form of post image adjustment. It’s come about by obtaining a new camera and a more suitable lens and the decision to become more serious.
I will try and answer one question raised how do I see color I have several books which help. These though are printed colors and cannot be relied on. Mostly I believe it’s what I remember and what looks correct to me. This of course means my perception which is not yours or any one else’s. I suspect especially among the less experienced this probably is their approach also. The use of histograms is all very new and needs more understanding in my case. If there has been articles or a good book to use I think the knowledge of this would help a lot of the less experienced. Years of experience which you guys have cannot be absorbed in a short time and I realise you allow for this.
I hope this clarifies some of the issues that new people find as is my own case .

Simon your observations on RAWTherapee are spot on, it is a beast to tame. As you know it is years in the making by a dedicated team of enthusiasts who have my admiration and respect but that does not make it any easier to use. It has been developed by scientists and engineers for scientists and engineers. I have found it and RAW Digger incredibly useful to get a better understanding of particular issues that were bugging me but I am unable to recommend RAWTherapee for general use.

Regarding the use of the colour checker and WB; one of the things I was keen to discover was how accurate was the Daylight pre-set in my camera when tested in ideal conditions at the cricket ground. I was gratified to find it was very accurate and probably better than the neutral white-grey-black test panels printed on the colour checker. There was some variation in the balance of the RGB values depending on whether I was checking light or dark tones which I decided was probably withing the variability to be expected from a printed test panel.

Your most important question concerns the extent to which we can rely of the WB pre-sets for different light sources. I don't know the answer as I no longer have access to a lighting lab where I have the appropriate calibrated sources to do the tests. My experience with DPP suggests that if you start with neutral picture style and choose the appropriate WB pre-set, you will be close to natural colour but may still need some fine tuning. This should be true for all serious RAW image processing software but who knows? I have yet to discover where the Adobe colour profiles come from, who measures them, how are they measured, what colour science is used to convert the measurements into final product?. In the case of DxO Labs it is safe to assume they do all there own measurements and you can see the results on their website but the underlying colour science remains a mystery. RAWTherapee is the only platform where you can see the underlying colour science and computer code as far as I am aware.

Ian, I would like to be able to help you with details of the testing etc behind the Adobe profiles - but I cannot. I recall a few years ago when I did some beta testing for Adobe, I asked a similar question which was met with a curt reply "We tested 30,000 images taken by professional photographers around the world"

A question if I may regarding the WB presets. I find the step between 'daylight' and 'cloudy', for example is typically about 1000K, irrespective of whether I am using the camera neutral, adobe neutral or a custom camera profile created with the X-Rite Colorchecker Passport. Invariably, I have 'adjust to taste' using the WB sliders in Lightroom to either warm up the daylight version or cool down the cloudy version. That is the reason that I prefer to adjust the temperature and/or tint of a known or expected neutral tone for equal RGB values. As you said in a recent comment, this technique relies on the accuracy of the assessment that the sample should in fact be neutral. If not, it is still necessary to adjust the temp / tint. Do you have any advice or tricks up your sleeve?
Thanks,
Bob

Just a question for Ian: I've used a number of different methods for colour correction, but I'm not closely familiar with how the XRite Colour Checker works. Specifically, when you use it to generate a set of colour profiles in varying lighting conditions, is the aim of the system to create images in which the image colours closely match how the observer saw the colours in the various conditions (i.e. if you photographed the same subject in different lighting conditions and applied the appropriate ColourChecker profile to each one, would all the images look different?), or is the aim to standardise the colours in each image to a reference set of conditions regardless of the light conditions at time of capture (in which case all of the final images would look the same)?