When I try to open a dng file in Photoshop (or gimp) it reduces the file to about 2 x 3 inches and 72 PPI. I can open the same file in iPhoto and it is full size and works fine. Why can't I get the same results in Photoshop? It ends up the size of a postage stamp and if I try to zoom in it gets all pixelated!
I have never experienced such a problem. Can you outline your conversion steps? Have you checked your Camera Raw settings at the bottom of the Camera Raw screen?