My goal is to (temporarily at least) get reliable colour values on screen and in my screenshots, in CorelDRAW 2017 on windows. If I screengrab and paste into eg GIMP, the colours shift. I think what is happening is that my screenshots are being converted to my monitor colour profile.
Here's the bahaviour I'm seeing: I draw a green rectangle (RGB #00ff00), and then screenshot my desktop or the CorelDRAW window, pasting the resulting image into GIMP leads to a much yellower shade of green. This is a color value change, ie using the GIMP eyedropper shows I now have #68ff00. I believe this is due to Corel passing everything through a monitor colour profile before showing the image, and means my sRGB green is being converted into a DELL factory colour profile instead.
After much searching I came across this thread: https://forums.adobe.com/thread/1815636 which seems to describe a similar issue. In that thread, two solutions to this colour shift are described, namely:
- Use sRGB as a monitor colour profile
- Assign the monitor colour profile to the screenshot, then convert to sRGB.
Corel 2017 does not have any way I can see to change the monitor colour profile, and I learned that it defers (on windows at least) to the OS. Changing my device colour profile to sRGB (Control Panel->Color Management, Tick 'Use my settings', add sRGB profile and set as default, restart Corel) indeed leads to #00ff00 appearing in the screenshot. The second solution gives yet different results.
Here's what I think is happening: Original configuration:
- Corel starts with #00ff00/sRGB internally.
- It converts this to a DELL colour profile found via an OS level setting and displays #68ff00
- Screenshotting my desktop leads to a file with an #68ff00 colour value, but with no embedded profile information.
- Pasting this in GIMP shows #68ff00
- Pasting back into corel means the colour is converted through the DELL profile a second time.
Setting my windows colour profile to sRGB leads to this:
- Corel starts with #00ff00 internally, sRGB.
- Display onto the monitor now does no conversion as this is also sRGB
- Screenshot gets #00ff00, no embedded profile.
- Pasting anywhere preserves #00ff00 value.
Using the other solution from the adobe thread above leads to this:
- Corel starts with #00ff00/sRGB
- Display is #68ff00/DELL
- Screenshot / pasted image is #68ff00/None
- Assigning DELL profile (GIMP->Image->Mode->Assign Color Profile..) leads to #68ff00/DELL (same as display output from Corel)
- Converting to sRGB (GIMP->Image->Mode->Convert to Color Profile..) leads to #0ef842/sRGB
In all cases, if I use Corel's export selection, or Corel->Window->Dockers->Color Proof Settings->Export Soft Proof, then I get an exported file with #00ff00 in it. However, nothing I can find in Corel will change the pixels on my displays/screengrabs to #00ff00. 'Proof colors' runs things through a printer profile and changes the display colour. Ticking 'Preserve RGB values' and setting the 'Simulate Environment' to sRGB, still puts #68ff00 on my screen.
My questions are:
- How can I temporarily bypass the monitor profile in Corel, to see and screenshot #00ff00?
- Why does the assign DELL profile/convert to sRGB process suggested above lead to #0ef842? Is this simply the fact that some information is lost in conversion, and that applying the same profile in reverse will never yield the original colour in general?
- What problems will I encounter if I use an sRGB profile for my monitor on a permanent basis?