I've just get the SB-600 to my D70s and I am really enjoining shooting with it, everything works simple and fine, the indoor photos are amazing (compared to what I did before). Yet, there is a point what I don't understand: when shooting in P-mode (for example the camera shooses 1/60 (set max) and F4,5) the camera doesn't warns about exposure and the exposure is fine. But, when I choose the A-mode (aperture priority) and I set F4,5 the camera sets 1/60 and WARNS that the photo will be badly underexposed. ...The photo is great, as always. Even if I choose some smaller (like F8 or F11) apertures the photo is not underexposed, because the SB-600 is powerful enough and the iTTL knows what to flash... The same in S-mode (shutter prio), too. Why does the camera warns about the exposure (as I would use it without the flash) when shooting in non-P-mode? Flash set to iTTL (non-BL for indoor). ISO 200 always. I checked the manual of my camera and flash, too , but didn't really found the answer.