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Radial gradient selection...

Jan 4, 2014, 08:26
Post: #1
Radial gradient selection...
Thanks to some excellent and timely help I got here [you know who you are], I've been fooling around with using a radial gradient on a mask to create a selection, then messing with the selection with various tools, e.g. saturation, blur, contrast. All this on a duplicate of the background layer, of course.

On my most recent attempt, I noticed "rings" in a portion of the finished image. Is the sequence in which I'm using the tools the problem? Should I work on the top layer first, THEN create the selection? Any suggestions?

Here's a crop from the image:

[Image: 5Wt8W7Vl.jpg]

Thanks
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Jan 4, 2014, 09:05
Post: #2
RE: Radial gradient selection...
Should I work on the top layer first, THEN create the selection? NO! Duh!
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Jan 4, 2014, 09:51 (This post was last modified: Jan 4, 2014 10:02 by rich2005.)
Post: #3
RE: Radial gradient selection...
You got your own answer but something to note

Gimp being an 8 bit editor (3 channels red,green,blue each 8 bits) loses colour information during editing.

example. http://imgur.com/w1oyI9d

top: open the color curve tool (set to log made) nice smooth curve.
bottom: A strong S curve applied results in banding.

example http://imgur.com/35H6M4o

Re-open the curves tool straight away an you can see the spikes where info is lost and the shape is no longer smooth.
note: this only shows during continual editing, export the image and reopen and it looks ok, even if it is not (another reason to save as a xcf).
You might get away with applying a gaussian blur which will smooth things out, very much depends on the severity of your editing.

** https://www.gimp-forum.net/ now answering questions**
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Jan 4, 2014, 11:01 (This post was last modified: Jan 4, 2014 11:38 by iForStyle007.)
Post: #4
RE: Radial gradient selection...
@Btavern: Looks good! If you mean the lines you see in each shade of the gradient, maybe it is the order you did it in.

Whatever you do, you might be better off making a transparent layer and putting the blend/gradient on there & changing the layer mode, then do any blurring after the gradient, and very little to start out with(test) as the last thing you do on that layer.

Any layer you put under your blur shouldn't affect the gradient blur.
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@rich: lol, I saw a related photo in your sample with a japanese show trying to figure out the realistic looking objects vs chocolate ones! http://imgur.com/gallery/x6T6i

Edit: vvvv XD duelly noted, I'll see you next week, have a great weekend vvvvv
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Jan 4, 2014, 11:27
Post: #5
RE: Radial gradient selection...
Great, thanks. You guys are the best. Lots of stuff here for me to work with. It'll probably keep me busy for a couple days, so you can all have the weekend off.
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