In article , fredrigl@math.uio.no says...
>mabbott@brutus.ms1.wits.ac.za (M ABBOTT) writes:

>| I just bought an F3 (upgrade from an F Ftn), and was wondering why
>| the meter can only be turned on after 4 frames have been fired since
>| closing the back. Is this normal?

>On my F3, the meter will only operate when the frame counter has
>reached `1', that is, the first picture. I haven't actually counted
>the number of frames fired until it operates.
>I find this feature a bit annoying some times. Some of the frames
>before the 1st can often be used on slide film, so it feels awkward to
>waste them.

Three winds normally brings you to the first metered frame with the
F3. BTW, you may not want to use earlier than the first frame with
slide film, since frame spacing is not correct until after the first
frame (I find it useful to cover the lens when winding so that the
slide cutter is not confused by the irregular spacing of exposed
leader frames with the F3).
Hope This Helps