Ahoy,

Joining the board to find out as much as I can. I'm a professional photographer & teacher in Seattle. I recently converted a couple of Chromebooks to completely free software (LibreBooks?) and now I'm trying to find ways of doing things in GIMP and Scribus that I could do with proprietary programs.

As a teacher I think it's important to teach ethics and morality to students, and one of my big contentions is that students should *always* learn on free software machines unless there is absolutely no other option. It's important to me that they learn to think and explore ideas and concepts and images and language, and NOT simply learn programs, especially commercial ones.

So I'm looking to do things my teachers -- Bert Monroy, Dan Margulis, Vincent Versace, John Paul Caponigro -- taught me to do with Photoshop (color by numbers, channel blending, LAB color variation, CMYK proofing etc) but using all free software. I learned Pascal and C ages ago, and I'm quite rusty. Now I've recently started learning Python, Ruby and C++ to see if I can't contribute to the community that way as well.

Things I especially want to accomplish:

1) fixing the Pointer to read RGB, CMYK, LCH, and LAB correctly (usefully);
2) easier channel blending both for contrast and color;
3) make the Color mode more accurate.

So I'll be asking for a lot of help! But I tend to give back more than I take (which is why my torrent ratios are always 5:1 or better ). If I can help anyone else, I will always do my best.

TL;DR -- "Hello world!"

@OmarW



Is that Libreboot and maybe an Asus chromebook with an ARM processor?

If that is the case, then is it running Debian linux? This will be a handicap for other than applications provided in the Debian repo.

For a regular linux (notebook with intel/amd processor), I would suggest trying the development version Gimp 2.9.5 which has greater color depth and some extra info, not LCH and Lab but the color picker does show HSV and CMYK.

When it comes to CMYK Gimp is not good. There is an old plugin separate+ that still works with Gimp 2.8.x which is used after editing to produce a CMYK image.

You might be better off exploring the capabilities of Krita, maybe not the best teaching tool, but does support various colour modes and higher bit depths.

Another place to ask questions is https://discuss.pixls.us/ which is more into quote...a place for photography (and free software) enthusiasts...unquote

Welcome Gimp Chat OmarW

Welcome to Gimp Chat! =)

Welcome fellow photographer and teacher!

I'm on Pixls.us, too

On this LibreBook (Acer C720 Haswell) here I'm actually running GalliumOS which is essentially Xubuntu, and I'm fine adding repositories and compiling by hand, so software isn't too limited. I keep coming back to GIMP because Krita and Blender et al are both too limited and too cumbersome to do a whole lot of color correction.

My goals aim at getting my students to prepare their work for gallery shows and books. So I rarely need or care about the things that most people think are "essential" in the GIMP or Ph*t*sh*p. I have precious little need of vector and text and animation tools. And unlike the hip photography crowd I rarely care about 16-bit files or the rest of the voodoo. But I do need RGB profiles, CMYK and LAB curves, and such because I have a workflow that relies on curves and channel blending for contrast, and LAB for color variation.

That's why I've started programming again. The CMYK/LAB support in GIMP has been inspirational It's so poor I figure I can do better myself. I've played with PhotoFlow and Separate+ and Delaboratory and Elle Stone's hacked cce-Gimp 2.9.5 but they're all limited for other reasons.

With any luck I'll make something useful enough to commit to the git repository!

--Om

Thats interesting, I use an Acer C720 (2 GM mem, 32 GB ssd) running Bodhi E19 linux (also 'buntu based) + Gimp 2.8.20 from the 'buntu ppa.

The plugin gmic http://www.gmic.eu might come in useful for colour curves.



Although I do wonder about the colour quality of the Acer display.
--------------
Edit: Not Gimp but might be useful for demonstrations/teaching is delaboratory Development stopped but it is non-destructive editing and I still dig it out for 'tweaking' purposes.

Easy enough to compile
https://code.google.com/archive/p/delaboratory/ maybe you could add to the code.
or it is in a 'buntu ppa
https://launchpad.net/~dhor/+archive/ubuntu/myway

looks like this http://i.imgur.com/jriXLBe.jpg

rich2005,

Delaboratory is very nice, but it moves the image one pixel up and left after editing.

edit, one day later: OmarW, I forgot to welcome you. That's not polite.
So...,

Welcome here OmarW.

Funny you should say that...

I just spoke with Delaboratory's original programmer. He's very sour on the open source world these days, but he seemed amused I was thinking about reviving his program. He's convinced no one wants it. I am almost inclined to view that as a challenge!

--Om

Is there an updated Separate+ plugin available for gimp 2.10.24? The plugin I have throws an error because it's from 2013. The OS I have is Windows 10 64 Bit.

There is no Gimp 2.10 update for the Separate+ plugin.

If you need a CMYK image, perhaps to send to a printing company, then the easiest way is use a program that supports CMYK colorspace. As far as freeware goes, you can use Krita. Easy to change from RGB to CMYK.

For Gimp 2.10 the way is a program CYAN see: https://www.gimp-forum.net/Thread-CMYK- ... 3#pid11743

Note: Most printing companies these days will accept a RGB image and do the conversion themselves with the provision that colours will change due to the reduced CMYK gamut.

I didn't say gimp update, I said updated Separate+ plugin.

...and neither did I, lets rephrase it

There is no update for the Separate+ plugin for Gimp 2.10



Sure, I wrote that. It is for Gimp 2.8

I know it's for 2.8, I just thought there would be an update of the plugin for 2.10. I downloaded the plugin again and tried it out. It's slow but useful.