[tex-live] Included .jpg figures to small

[Gunther Rens]

Hi,
I'm trying to switch from MikTex on PC to Live Tex (TexShop) on mac.  
I'm trying to typeset files which turn out fine on MikTex. Everything  
turns out exact the same exept for my .jpg figures: they are given the  
right amount of space in the text, but for some of my figures all I  
get is very small thumbnail-like figure on the botom end of that space.
It seems that only the figures I prepared in photoshop are affected. I  
save my figures as RGB color, 8 bits/channel, high quality (8). I use  
the graphicx package to include on TexShop v2.14.
Somebody an idea?
Thanks!
Gunther