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05-27-2013, 03:29 PM   #1
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Join Date: May 2013
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using the 645 fa 120mm f4.0 lens

I am a bit embarrassed to admit that I am not sure how to use this lens. I can't find the "owners manual" if there is such a thing. The auto focus on the 645nii is good but it seems to have to start completely out of focus and then focus in on the subject ( and it is slow). Just very different than 35 mm lenses and that's ok. But what does the full and limit switch mean on the lens barrel and If limit = macro , can that be used when the lens ring is on "A"? Thanks for any help. As I said I am a little embarrassed since I have used minolta SLRs since the 60s but I am just a little bit at a loss here. THanks Norm

05-27-2013, 03:38 PM   #2
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The limiter switch limits the AF range to infinity-5m (I'm not sure of the exact number) if your focus is past 5m, or 5m-minimum if your focus is below 5m. Its goal is to speed up the AF so that the AF never enters macro range if your shooting at a distance, and vice-versa. This has nothing to do with the aperture ring setting.

The reason that the AF is slow is that the focusing throw is generally much longer on macro lenses. When shooting macros, you'll usually want to be in manual focus mode anyway.

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