Nikon F6 and the focus mode switch for non-AF lenses.

So I know what the S and C are for, but the M on the switch has me confused. According the manual (p.61), it enables ais lenses to be able to confirm focus with the circle indicator in the viewfinder. However, when in the S mode, my ais lens is also able to have focus confirmation via the circle. So the M setting seems redundant.

The other weird thing is that when the switch selects S or C, it feels like a typical electric switch (ie, easy to flip). But when I flip it down to M, it seems to have some kind of mechanical linkage behind it (and it's significantly harder to turn the switch to M). However, when I take the lens off and peer inside when going to M, I don't see any visible movement in the innards, either.

I think I'll just leave the switch on S full-time, since the mode selection is just one more thing to forget when changing from AF lenses to non-AF lenses. (I have enough trouble remembering to switch over the non-CPU lens setting in the menu).

Any info on this mystery would be much appreciated.

Thanks,

Evan

I don't have an F6 but I have other Nikon AF SLRs with the screw drive for autofocus. Flipping the switch to M retracts the AF "screwdriver" from the lens mount (try it again and watch the screwdriver). If you have an older AF lens that is not AF-S, this disengages the body AF motor from the lens AF gears, so you can manually focus the lens. For a lens that is strictly MF, setting to M is either redundant or tells the body not to bother AF'ing.

In the M mode, an autofocus lens will behave like a manual focus lens--you'll have to focus it yourself. This is handy when you want to set the focus on something and not have the camera decide it should focus on something else that might pass through the frame.

reddesert said:

I don't have an F6 but I have other Nikon AF SLRs with the screw drive for autofocus. Flipping the switch to M retracts the AF "screwdriver" from the lens mount (try it again and watch the screwdriver). If you have an older AF lens that is not AF-S, this disengages the body AF motor from the lens AF gears, so you can manually focus the lens. For a lens that is strictly MF, setting to M is either redundant or tells the body not to bother AF'ing.

Click to expand...

Got it! Not sure why I didn't notice that before. Guess I just needed my higher powered reading glasses. Thanks RD! (and it's good to know that I can just leave it on the S setting)

Pieter12 said:

In the M mode, an autofocus lens will behave like a manual focus lens--you'll have to focus it yourself. This is handy when you want to set the focus on something and not have the camera decide it should focus on something else that might pass through the frame.

Click to expand...

That makes sense, too. Thanks Pieter.

I think you will find that turning the switch to 'M' will also withdraw the drive pin into the body, because if you don't do that using an AF lens you will not be able to use it on manual. Why is it there, well some folk actually still like to use manual focussing out of choice. especially with tricky focussing points. Like me when I am using my AF Macro lens.