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01-02-2011, 11:02 AM   #1
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Manual Focus Lenses on 645D

So am I to assume that all of the "A" 645 lenses manual focus are poor performers on the 645D? Because they are impossible to get accurate focus?

I guess I will no on Monday when I get my 645D in the mail, I purchased for 300.00 the 120mm Macro "A" version off the lens,
Yikes.

Steven

01-02-2011, 11:49 AM   #2
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QuoteOriginally posted by kuau Quote
So am I to assume that all of the "A" 645 lenses manual focus are poor performers on the 645D? Because they are impossible to get accurate focus?

I guess I will no on Monday when I get my 645D in the mail, I purchased for 300.00 the 120mm Macro "A" version off the lens,
Yikes.

Steven
Check my posts of an amateur's first impressions, where I give an example of the 55mm f2.8 manual focus lens. It shows where the lens was focused, a spot in front, and behind, to show DOF. I included 100% crops. This may help you decide if MF will work for you. My limited experience is, using shorter focal length f2.8 lenses in bright outdoor light at f11 or f13, provided adequate DOF and focus was accurate enough to make me happy. (YMMV). I do also have several AF lenses, so as I go up the learning curve, I will post any insights that may be helpful to others.
Dave
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01-02-2011, 11:56 AM   #3
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Steven:

I understand your apprehension, having parted with my 10k when I got a 645D two weeks ago. In short, I don't think it's a big problem. Is it a challenge, yes, but I'm very happy with my results so far. Unless you routinely shoot wide open, I suspect you will be too. Lloyd Chambers had no trouble with the MF 75mm. He is having trouble with the 45 and 200. Those are among the weakest of the 645 lenses and any used lens is a gamble, so the problems he is having may be a consequence of the history of those lenses. I have the 120mm in the A and FA versions and I always use the A version for macro. Its focus ring is much more precise and AF lenses don't know where to focus unless you go to the trouble to tell them. Relax, if you get a good copy, you'll love the lens.
01-02-2011, 11:59 AM   #4
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It is not "impossible" to get accurate focus with a manual focus lens. It's just challenging, and then not in all circumstances. Once you get familiar with the system and lens performance, I think manual focus will become workable in a lot of cases. I've tried manually focusing some of my FA lenses just to see how good a job I can do. I've had some misses and some hits. Hyperfocal focusing works okay, and a combination of focus bracketing or double-checking via digital DOF preview or image review works when I have time with relatively static subjects.

I also have an "A" 120mm Macro coming next week. I plan to use it for macro work, where I would never use autofocus anyway. I don't expect to have any trouble with it. I also recently got ahold of a 67 105mm f/2.4 and it works well manually focused when I have time to dial in or when I'm really paying attention. Chris Willson (Travel 67) seems to be doing a bangup job with this combination.

We get used to all the modern digital and electronic aids to photography, but people did well without them for a century and a half. Sure, more capable tools are better in some ways. But to my mind it's more a matter of convenience and fine tuning the last few %, not good vs. poor or possibility vs. impossibility...

01-02-2011, 01:24 PM   #5
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I agree with Royce.

The only manual focus lens I have for the 645D is the 600/5.6. It is relatively straight forward to see when it is in or out of focus. It certainly helps to have the finder in focus and proper correction in your glasses if you wear them. (It is surprising how many people don't realize they are going around with minor focusing errors like uncorrected astigmatism and therefore cannot distinguish fine details except on an enlarged computer screen.)

I've used the 150/2.8 and the 75/2.8 in manual focus mode and they work just fine too. The AF and my manual adjustments agree.

While admittedly, a lack of a center microprism, or other focusing aid, makes it more difficult to judge focus because the end point is more subtle, I wonder if a contributing problem may working too fast and thereby missing the plane of focus. Manual focus requires more accuracy than AF from the user.

To further compound the problem (but still related to accuracy) is the larger format itself: the DOF is less with MF and LF. When focusing the 600/5.6 lens on the 645D at 5m (it's closest focusing distance), the DOF is less than 1/4 inch. Certainly the DOF is greater for wider lenses, but they still have less DOF than their 35mm counterparts.
08-02-2012, 06:06 AM   #6
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Can't you use the Focus indicator on the 645D?

On my K-5, when using older manual focus lenses, the camera can tell you when an image is in focus. If the camera is in MF mode, when you press the shutter release button half way and turn the focusing ring on the lens, you will get a beep and an indicator light in the viewfinder when the image is in focus. No need to "eyeball" the focus. It works very well. I thought the 645D and the Hasselblads provided this same feature to facilitate use of older lenses. I don't have a 645D yet, but would like to know if this is true.
08-02-2012, 10:57 AM   #7
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This does work on the 645D, but I find it not as helpful as I'd like. It will often beep a bit too soon and continue to say it's in focus a bit too long as I slowly move the focus ring.
08-02-2012, 01:20 PM   #8
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My experience with the A120 is that it's an excellent lens if used correctly. Wide open the DOF is incredibly narrow and will probably require focus stacking, depending on your subject and intent of course. Stopped down it's much easier to focus. I use mostly manual focus lenses on my 645D and rarely miss a shot due to focus, but I'm generally shooting landscapes in the f8-f16 range.

08-04-2012, 04:04 PM   #9
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you guys are really ticking me off.what's with this thing against manual focus lenses?what do you think the guys who shot for nat. geo, back in the day, used?ansel adams large format lenses were all manual focus.if you feel at a disadvantage without auto focus, fine!! but don't put the practice down.
all but one of my 645 lenses are manual focus and i don't feel at a disadvantage
p.s. what about you guys who shot back in the day? did you spend your time cussing at the camera and hopeing for the day of auto focusing?

Last edited by bull drinkwater; 08-04-2012 at 04:23 PM.
08-04-2012, 06:29 PM   #10
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Manual focus lenses i.e. A series work just fine for me, although macro is a bit of a challenge for me though . . . .

I can understand if your eye sight is not what it used to be, and with failing visual acuity manual focusing become forever more difficult.
03-11-2013, 05:51 PM   #11
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QuoteOriginally posted by jwjohnson Quote
This does work on the 645D, but I find it not as helpful as I'd like. It will often beep a bit too soon and continue to say it's in focus a bit too long as I slowly move the focus ring.
i'm so sorry to see so many panic at the thought of having to manual focus.whhat the hell is happening?i only have one af lens and i'm doing fine.
03-11-2013, 08:56 PM   #12
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I think it largely depends on what you're shooting. With landscapes I could do without any autofocus at all and do just fine. If you're shooting people or wildlife, then yeah, autofocus is going to be very nice to have. If you're shooting very fast moving objects (sports, wildlife) then the 645D probably isn't the camera for you to begin with.
03-19-2013, 12:02 PM   #13
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QuoteOriginally posted by bull drinkwater Quote
i'm so sorry to see so many panic at the thought of having to manual focus.whhat the hell is happening?i only have one af lens and i'm doing fine.
I wasn't trying to disparage manual focus lenses. I was answering a question on how well the focus assist worked with manual focus lenses. Personally I use manual focus most of the time, but I like having the option of auto-focus since for some scenes my eyes don't work as well as when I was 18.
03-19-2013, 12:05 PM   #14
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I don't find the focus assist light/beep to be very helpful. It basically means "you're close" or in the ballpark, and with the shallow DOF of the 645D it just means you're close, as there's a 'range' in which the light will stay on.
03-20-2013, 04:28 AM   #15
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QuoteOriginally posted by Ryan Tischer Quote
I don't find the focus assist light/beep to be very helpful. It basically means "you're close" or in the ballpark, and with the shallow DOF of the 645D it just means you're close, as there's a 'range' in which the light will stay on.
i've noticed that too. It would be great if there was a way of adding Live View to the next incarnation of the 645D
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