[Gimp-user] GIMP changing colors in image.

[rich2005 <forums gimpusers com>]

> Hi there.
> I am probably way in over my head even posting in here.
> But maybe i get props for trying to learn. 
> I am using GIMP to do some super basic prep for images of my art for
> online sales.
> Some images end up being drastically different colors from the
> original painting and photo file once uploaded into GIMP and then will
> also save that way when I export tifs as jpgs for web use.
> I know it's unlikely. But is there a trick or setting to disable that?
> Is there some basic thing I am missing?
> Can anyone explain to me what is happening or help me trouble shoot?
> Thanks so much!
> I would love to preserve the original color as much as possible.

If you are taking the photographs of your artwork then it is probably a hardware
issue.

First, what is the format the camera uses? RAW or possibly jpeg. Going from RAW
into Gimp involves a conversion with all sorts of tweaks where colours can be
adjusted. Jpeg from a camera on the other hand is most likely RGB colour profile
and not all colours are included. Look up color space

https://en.wikipedia.org/wiki/Color_space

A fix can be as simple as "auto white balance" in Gimp, but usually more is
needed. You should take care about the lighting conditions when the photographs
are taken. A bit of reading here:

http://www.cambridgeincolour.com/tutorials/white-balance.htm

Then the computer display. For best results the monitor should be calibrated.
Monitors straight out-of-the-box will have their brightness set too high. There
are simple ways to get sensible setting. see:

 http://www.cambridgeincolour.com/tutorials/monitor-calibration.htm

However, all your potential customers will also have their monitors un-adjusted
so they will get a wrong impression of your work whatever you do. Why not
include a disclaimer on your web page.

rich: www.gimp-forum.net

-- 
rich2005 (via www.gimpusers.com/forums)