Nope, nothing about the image should be affecting whether you get a security token error.
I would guess that the security token thing is some weird issue related to your firewall or web browser or session time-out or broken session cookies.
You mentioned something about a separate error
it just says error DSCF2610.jpg Upload of file failed.
and I was guessing that that error might have something to do with exceeding file size limits.
Imagine a pathologically idealistic, anti-religious, culturally-relativistic, iconoclastic, socially-irreverent, sociologically-progressive signature line here. Or don't.