This is defined by
a) whether the 3DS file is a scene file ratehr than just geometry and has timeline info attached (in which case you cannot extend it in PS even; nasty bug)
b) whether or not the animation panel in PS was open and thus accidentalyl a time range for animation defined
Check those things and work your way through...
Ok, please guide me through this if you have a little time to spare. How can I check whether the 3ds file is a scene file or not? And where is the animation panel located in Photoshop? Don't get me wrong I'm kind of new in all this...
Ok, I just opened up a 3ds skeleton model in Photoshop, turned on the Animation Panel and I can see it only contains 29 frames. Do I assume this is timeline info contained that I can't change or is there a way to extend the timeline lengtth? Is there a workaround outside Photoshop?
I had this problem exporting a .3DS model from Sketch Up. I exported as a .OBJ instead and brought it into Photoshop. Seems to work fine so far.