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+--- Thread: How to replace a background - not cutting out (/Thread-How-to-replace-a-background-not-cutting-out)
How to replace a background - not cutting out - enginestar - 06-27-2018
Say I take pictures of an object on a 1 color background...
Is it possible to just get rid of that color?
Say cream or green or black?
Maybe roughly isolate the object and then apply a tool to turn the background to be white?
Thanks.
RE: How to replace a background - not cutting out - Espermaschine - 06-27-2018
Not 100% sure i understand what you want to do....
Do you want to
a) non destructively replace a single coloured background ?
or
b) get rid of a single coloured background ?
For a) you use a layermask
for b) ofn-erase-background
https://www.gimp-forum.net/Thread-ofn-erase-background
Both techniques could be combined into one, by applying ofn-erase-background on a duplicate, then alpha selecting the erased background and applying the selection as a layermask to the original image.
Then you can delete the helper duplicate and put a background in the colour you want, behind the original image with the layermask.
RE: How to replace a background - not cutting out - Ofnuts - 06-28-2018
(06-27-2018, 10:15 PM)enginestar Wrote: Say I take pictures of an object on a 1 color background...
Is it possible to just get rid of that color?
Say cream or green or black?
Maybe roughly isolate the object and then apply a tool to turn the background to be white?
Thanks.
Yes, but it is better/easier if the color is really uniform (unless you have a good lighting you'll have level differences), and/or different from anything else in the object (ie, green-screen) so that you can make selections based on the value of specific color channels. More attention/technique in the shot can save hours of editing.
If you want a white background anyway, the pro technique is to blow out the background (often made of white vinyl) with an additional flash behind the subject. If you are shooting small objects, invest in a shooting tent (rather cheap, but you can also build one yourself).