I've got a 7-8oz veg tan shoulder that I'd stored in a roll (no room to store flat alas.) Having finally gotten my other projects complete, I pulled it out to start the project I bought it for which will require the entire shoulder, uncut.
Unfortunately, though I thought I'd had it out of the sun, the outside of the roll (approximately half) is distinctly darkened. This picture more or less gives a crappy idea of how much darker the exposed portion is:
While it's not as bad as some leather 'tan lines' I've dealt with, this particular project will suffer if I can't even out the tone. By the time I'm done, most of the piece will be stained or antiqued, but I'd really like to start from an even base.
I'm fantasizing about masking the dark part and taking the shoulder out into direct sunlight for short stretches (or for that matter, I have a silk screen UV lamp and timer, but it's pretty potent.) It will be difficult, given the requirements of this project, to cut pieces off for testing. Maybe I can trim a few slivers....
In any event, does anyone have anything like a rule of thumb for direct sunlight exposure and darkening? Or a 'enlightening' anecdote about handling a similar issue?
Thanks in advance!
--tim