The cap is ....well captivating. Sorry I was going to say amazing, but I just couldn't help my self!
Yeh, pictures tend to look different on different screens. LCD monitors very greatly. They have what they call contrast ratio, which is the differnce between the blackest black and the whitest white, or something like that. Also with LCD's the angle that its vied at can make it look lighter or darker.
On old style CRT monitors, depending on how long(age) the screen has been in use can make a differance as well.
If you haven't completely given up, even though the reflection of the pen in the table surface looks neat I would try a different background.