- This topic has 4 replies, 2 voices, and was last updated 9 years, 4 months ago by
.
-
Posts
-
Dear all,
I attached a simple image file with 3 squares. Each of them is composed of a solid center surrounded by alternating bars. When you look at the image from far enough, the solid centers should dissolve into the surrounding bars because the average bar color match the intensity of the center. At least this is what should happen if everything from the software that reads the image all the way to the monitor is properly setup for sRGB.
Indeed, if I leave my monitor and system in their default state, this is exactly what happens: I can’t really see the boundary between the centers and the surrounding bars.
However, when I calibrate the monitor using DisplayCal, the center looks clearly distinct from the surroundings. Am I doing something wrong? Do I understand the problem incorrectly? Is there some setting I should have used to respect this grayscale behavior?
My monitor is a DELL UP3216Q and I am running Unbuntu 16.04.
Kind regards,
Diego
Hi,
When you look at the image from far enough, the solid centers should dissolve into the surrounding bars because the average bar color match the intensity of the center.
Yes, but only if the overall tone response matches the assumption under which the gray center of the test image was created. It is quite common that such images are created with the sRGB tone response curve in mind, which is close to a gamma of 2.2. Furthermore, in a color managed environment, you have to assign a suitable working space profile (i.e. in this case sRGB) to the image (in case it doesn’t come with an embedded profile), and irrespective of actual monitor gamma, the image will then look correct in color managed applications (in conjunction with an accurate monitor profile).
Thanks for the message!
When I select the profile generated by displaycal in the System Settings, I can clearly see a change, so it seems to be doing something.
I am using GIMP to view the image. I believe the it is set to sRGB, as reported by the “identify -verbose” command from ImageMagick.
No matter how I configure GIMP, either trying to use the system monitor profile, or directly loading the file into it, the squares do not match.
If, however, I leave the default monitor profile on System Preferences, the image looks right.
Can you help me troubleshoot this?
I am using GIMP to view the image.
It would be good to check with another program, i.e. Firefox with
gfx.color_management.enablev4=true and gfx.color_management.mode=1No matter how I configure GIMP, either trying to use the system monitor profile, or directly loading the file into it, the squares do not match.
Post a screenshot of your Gimp color management settings please, and attach your monitor profile.
