[Gimp-user] Documentation - Behind/Color Erase modes
I do a lot of traditional drawing, so one of the common tasks I perform in GIMP is cleaning up the background after scanning a character I've sketched on paper (erasing stray pencil flecks and so on). I've frequently used the Erase (with alpha channel) to perform this task, because it means I end up with a transparency that I can paint some manner of digital backsplash underneath. My general process for doing this was: 1 - Duplicate the layer 2 - Perform a full Color to Alpha transformation on the lower layer (white as background) 3 - Use the Eraser on the upper layer, with a soft-edged brush, to clean up the background. Any mistakes during the process I can clean up using the Alt (anti-erase) modifier. This yields a smoother foreground-background fade around the edges than simply the Eraser on a single layer. But recently I discovered the faster way of doing this task: The Color erase painting mode, which performs a Color-to-Alpha transition as part of any other drawing operation. So I don't need to worry about managing multiple layers anymore. However I do need a function to perform the inverse, so I can compensate for mistakes... ...and it dawns on me that the Behind paint mode is exactly what I'm looking for here. All I need to do now is set up a keyboard shortcut to toggle between the two modes and I'll be good to go. Anyway, it should be noted in GIMP's online manual (http://docs.gimp.org/2.6/en/gimp-tools-paint.html#gimp-paint-mode-examples ) that the Behind and Color Erase blending modes are inverse functions of each other, with color erase transforming solid color to alpha and behind transforming alpha to solid color. (Should I file this on the bugtracker?) -- Stratadrake strata_ran...@hotmail.com Numbers may not lie, but neither do they tell the whole truth. ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Crop tool - highlight intensity
Not that I know of, but while we're on the subject I do notice that the tool's highlighting isn't particularly useful if you happen to be working with an exceptionally dark image -- as an idea, perhaps instead of darkening the outside areas by 50%, it could fade its opacity by 50%? -- Stratadrake strata_ran...@hotmail.com Numbers may not lie, but neither do they tell the whole truth. Date: Fri, 5 Aug 2011 15:28:47 -0500 From: cr33...@gmail.com To: Gimp-user@lists.xcf.berkeley.edu Subject: [Gimp-user] Crop tool - highlight intensity Hi list, Is there any trick to increase the intensity of the highlight option of the crop tool? Thanks, Chris ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Explicit manipulation of Alpha Channel.
Date: Tue, 19 Apr 2011 22:42:24 +0200 From: ofn...@laposte.net To: gimp-user@lists.XCF.Berkeley.EDU Subject: Re: [Gimp-user] Explicit manipulation of Alpha Channel. This is what layer masks are meant for. More specifically, on the Layers menu, select Add Layer Mask, with full opacity (white), then click on the mask icon from the Layers toolbox (it will appear next to the source layer) and start painting on it like you would any grayscale surface. (You can toggle the Show Layer Mask option any time you want to see exactly what the mask layer by itself looks like.) You can keep it this way for working, or when finished, select Apply Layer Mask to transfer the layer mask into the source layer's alpha channel. -- Stratadrake strata_ran...@hotmail.com Numbers may not lie, but neither do they tell the whole truth. ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
Re: [Gimp-user] Rule of thirds or golden ratio tool (suggestion)
From: rob.antonis...@gmail.com Date: Fri, 4 Mar 2011 13:07:05 -0500 To: aldeaglo...@gmail.com CC: gimp-user@lists.xcf.berkeley.edu Subject: Re: [Gimp-user] Rule of thirds or golden ratio tool (suggestion) hello I'd suggest a tool for photographic composition that has as options the rule of thirds or the golden ratio. So you can do photo composition on the fly and crop the image based on it. The Crop tool supports this feature already, just like the rectangle select. (At least as of GIMP 2.6 ... you didn't say which version.) It would probably not be too difficult to write a script-fu to add guides to the current image/layer for these divisions as well. -- Stratadrake strata_ran...@hotmail.com Numbers may not lie, but neither do they tell the whole truth. ___ Gimp-user mailing list Gimp-user@lists.XCF.Berkeley.EDU https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-user
