Hello everyone,
I'm not sure whether this is a right place to post my wish but I can't find any better.

It would be really great if the Sample Points dialog had "Sample average" option as the Color Picker Tool has, because it would certainly improve color correction experience. Without sample average it's not exactly more difficult to do color corrections in Gimp, but it's much more error prone because you can accidentally select the pixel with color lot of color noise.

I think my wish is easy to implement because the functionality already exists in Gimp's Color Picker tool.

Also I think it would be nice if the Sample Points dialog could show the before/after pixel values (divided eg. by slash or by enclosing one of the values in braces) but it's not something I give a high priority at all.

have a nice day, Lukas

2010/7/8 Michael Natterer :

On Thu, 2010-07-08 at 19:09 +0200, Lukáš Jirkovský wrote:

Hello everyone,
I'm not sure whether this is a right place to post my wish but I can't find any better.

It would be really great if the Sample Points dialog had "Sample average" option as the Color Picker Tool has, because it would certainly improve color correction experience. Without sample average it's not exactly more difficult to do color corrections in Gimp, but it's much more error prone because you can accidentally select the pixel with color lot of color noise.

I think my wish is easy to implement because the functionality already exists in Gimp's Color Picker tool.

Also I think it would be nice if the Sample Points dialog could show the before/after pixel values (divided eg. by slash or by enclosing one of the values in braces) but it's not something I give a high priority at all.

I wanted to add this in the original sample points implementation, but never managed to do it and forgot it in the meantime.

Can you file that as enhancement in bugzilla please?

https://bugzilla.gnome.org/enter_bug.cgi?product=GIMP

thanks, --mitch

I posted both wishes to the gnome bugzilla: https://bugzilla.gnome.org/show_bug.cgi?id=623940 https://bugzilla.gnome.org/show_bug.cgi?id=623941

Have a nice day, Lukas

2010/7/9 Alexia Death :

Can you tell me how you use the sample points? I'm interested in your use cases, to better understand different work flows.

-- --Alexia

I'll try to explain (maybe I could try to record a short video showing my work flow if my description is incomprehensible). When I open a photo I look for areas where I know how the color should look like. I usually look for neutrals (asphalt road, gray clothes) first and put some sample point here. Then I add sample points other places with known color like leaves. Then I open curves dialog and I try to set the curves so the color color "matches theory". In other words I try to match the curves so the neutrals are approximately neutrals and eg. leaves mentioned contains most green and bit of red but almost no blue. This is where the sample points are really useful because I see the numbers for all selected places at the same time.

Lukas

2010/7/11 Alexia Death :

On Sunday, July 11, 2010 11:51:47 Lukáš Jirkovský wrote:

I'll try to explain (maybe I could try to record a short video showing my work flow if my description is incomprehensible). When I open a photo I look for areas where I know how the color should look like. I usually look for neutrals (asphalt road, gray clothes) first and put some sample point here. Then I add sample points other places with known color like leaves. Then I open curves dialog and I try to set the curves so the color color "matches theory". In other words I try to match the curves so the neutrals are approximately neutrals and eg. leaves mentioned contains most green and bit of red but almost no blue. This is where the sample points are really useful because I see the numbers for all selected places at the same time.

Thanks for the explanation. Its a very interesting use of the sample points :) A video perhaps would bean overkill but I would like to see screenshots of before an after with some sample image, if its not too much of a bother.

Best, Alexia

I made some images to show how I use sample points. Image [1] shows initial setup and image without any corrections. Screenshot [2] shows the image while working on it using curves and sample points. Image [3] is the actual result, where I did correction on b in Lab decomposed image to get rid of the blue shadows atop of the curves.

[1] http://blender6xx.ic.cz/pub/sample_points/screen_1.png [2] http://blender6xx.ic.cz/pub/sample_points/screen_2.png [3] http://blender6xx.ic.cz/pub/sample_points/_MG_1242-corrected.jpg

Lukas