Using layers in photoshop 7

[5ash]

I find that I can only create layers that are 8 bit , have to convert 16 bit tiffs to 8 bit to create a layer. Am I doing something wrong or can photoshop 7 only handle 8 bit images as layers. If so is there a version of photoshop that will handle 16 bit images for creating layers? Would appreciate some advice.
Philip

[gb_astro]

Philip, looks like 16 bit layers began with CS (8).

gb.