Thread:Project:Support desk/Problem with image changing colour - different on logo & main page for same image

Problem with colours in pages vs in logo at top left

I'm using a .jpg file. When I have the file as the image as the logo at the top left the colours are correct.

When I have the same file in a wiki page, the colours are wrong.

What happens, particularly, is that, when it is set as an icon, main letters are dark green. You can see how it should be here:

logo the correct colour

When it is in a wiki page, the image becomes light- green - as it is here:

logo the wrong colour

Why the difference and how can I adjust it?