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04-09-2012, 11:15 AM   #1
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Using 645 A lenses with 645D

My third and final question on here today, so thanks for your patience so far!
Am I right that when using 'A' lenses and pressing the shutter button halfway, the autofocus confirm light comes on regardless, and has absolutely no relevance whatsoever?
Focusing is purely down to what you see in the viewfinder, and what you check in the review afterwards?

04-09-2012, 11:34 AM   #2
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You've got to focus the lens yourself, but I think that the AF confirmation system will tell you whether or not things are actually in focus.

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04-09-2012, 11:38 AM   #3
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I'm not sure about the 645D, but with my 645N the focus confirmation light works with any manual lens to let me know that the image is in focus.
04-09-2012, 12:03 PM   #4
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I have the 645 35mm A. If you hold the shutter button halfway and then manually focus the lens, it will illuminate in the viewfinder and beep (assuming that setting is turned on) once the area selected is in focus. I don't find it terribly useful though, as I find it tends to offer somewhat of a 'range' of 'in focus' rather than a precise point, and isn't as precise as an actual autofocus lens, or even my eyes (20/20 vision) for that matter. But it tells you when you're very close, and depending on your aperture, perhaps 'close enough'.

The good news is that the viewfinder is sharp and bright and unless it's dark out like pre-dawn or after sunset, I've never had an issue getting focus sharp (again though, 20/20 vision!). I do often find myself checking focus in my landscape use if I have time by zooming in to about 8X, and making sure my selected aperture keeps everything I want to be tack sharp.

04-09-2012, 01:01 PM   #5
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AF confirmation works with the 645D on a manual lens (A)
04-09-2012, 02:23 PM   #6
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Thanks for the replies.
I've been trying focusing with the 35mm A also and the focus light comes on, but it's not what I would call in focus (or there's a wide latitude).
Anyway as you say it's a very good viewfinder, but a bit more magnification would help - my eyes no longer give me 20/20 vision!
04-09-2012, 05:33 PM   #7
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Hi, have been using this lens for approx 3-4 weeks, as mentioned the conformation does come on, but also as you say a bit of latitude is used as can come on at slightly different points.
I have tested and found for Landscape use, focussing at infinity, every one of my shots is TACK sharp, from approx 1m in front out to infinity, awesome lens.. for that <1m can always focus stack, or not worry as i have found it to be ACCEPTABLY sharp.. especially when viewing a print of a landscape.. Its all personal choice and preferences, nothing more or less. Have fun and happy shooting with it...

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