It never ceases to amaze me how some merchants make their thumbs or previews so dark you cannot see the merchandise. Now, admittedly, my monitor is set with its brightness low - I find that easier on my eyes, which are pretty light sensative. But most thumbs from the good vendors show up fine, if just a trifle dark. If I have to turn up the brightness high enough to burn the monitor to try and see your product, the thumb is too dark - and if I can't see it, I won't buy it!