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04-30-2009, 03:15 PM   #1
julianactive
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Interesting article on manual vs. autofocus

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Last edited by julianactive; 05-17-2009 at 09:55 AM.
04-30-2009, 04:01 PM   #2
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My experience is that autofocus is not as consistently accurate as manual focus. I tend to manually focus as much as I can, and use a split prism focus screen in my K10.
04-30-2009, 04:26 PM   #3
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I'm not surprised. He used Canon and Nikon.
04-30-2009, 05:30 PM   #4
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QuoteOriginally posted by flyer Quote
I'm not surprised. He used Canon and Nikon.
Yo! Spoken like a true Pentaxiam!!

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04-30-2009, 05:52 PM   #5
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Looks like a FF/BF problem?
04-30-2009, 05:55 PM   #6
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QuoteOriginally posted by EricT Quote
Looks like a FF/BF problem?
eh? I don't know what else to say!

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04-30-2009, 06:02 PM   #7
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I have been pretty happy with my autofocus, but I think I will do more manual focus just to test the waters. I bought a split prism screen for my K200D in order to use a M1.4 lens I bought. That sucker at full open has a depth of field as thin as a frog hair.

04-30-2009, 06:36 PM   #8
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Canikon is always being praised for their fast autofocus, and Pentax is being complained about as being slower. Well, could it be that faster equals inaccurate, and slower equals more accurate! Things take time, no way around it.
04-30-2009, 09:05 PM   #9
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QuoteOriginally posted by julianactive Quote
I have been pretty happy with my autofocus, but I think I will do more manual focus just to test the waters. I bought a split prism screen for my K200D in order to use a M1.4 lens I bought. That sucker at full open has a depth of field as thin as a frog hair.
Even if AF worked perfectly, MF is still a useful skill. The AF sensors don't know what your subject is or where the zone of focus should be. They can only find something to focus on and tell you where in the frame that was. Sometimes that's good enough and sometimes it's not. When you can focus yourself, this problem and flaws in the AF system won't stand in your way.
04-30-2009, 09:38 PM   #10
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I use MF for everything that doesn't move, can be pre-focused, or for pure snapshots. Auto-focus finds best contrast or phase or whatever; my eye finds the focused image I want. Sometimes the two are definitely not coincident! Besides, I've got a lot of older non-AF lenses that are designed to make MF easy.

As Julian said, DOF is a bear at wide apertures - more so than you might realize. A split image finder really helps, although a split prism can be problematic with moving targets - but not impossible. (Some really great sports/action photos were made long before AF and burst mode. Try sports action shots with a YashicaMat TLR and flashbulbs.)

My opinion is that a lot of the focus issues we see today are generated by people that aren't accustomed to a GOOD viewfinder, don't realize just how important shallow DOF really is at wide apertures, underestimate shutter speed/camera blur effects and that rely on AF because they can't truely see focus errors in their viewfinder.

And, oh yeah, when was the last time you checked your diopter adjustment? I don't know how it happens, but mine wanders off by itself and plays merry games with perceived focus.

Suggestions:

Explore/review the DOF program/chart in the sticky above this forum. If I pre-focus on where a bird's claws will be on a branch - the only thing available - it's not unusual to see the eyes/beak and tail beginning to be OOF just an inch and a half or so out of the focus plane at 7-8 feet.

Find and read some of the intermediate/advanced sports photo technique books of the '50-60's. Then turn off AF and treat each shot as though it was on negative film for a month and practice.

I'll bet that within a week (1) you'll get frustrated with your viewfinder, and (2) your throwaways will increasingly tend toward exposure finess and composition errors rather than focus and bokeh. (You DO use that DOF-switch feature, don't you?)

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04-30-2009, 11:35 PM   #11
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Ever since a Canon film Rebel left me half a day's autoshow pics out of focus, I went manual focus and switched to Pentax. Partial user error and inexperience.

But anyhow the debate really comes down to how you view your equipment/photo taking process.

Like AF/MF is kinda like automatic/stick shift. How much automation/control do you want in your photography?

For me as an MF guy, I think alot of the bonus to going manual has already been said. There's that element of control that you cannot get from AF. A camera has no way of knowing what is the subject, especially in the spatial sense. It merely tries to predict based on a variety of factors, algorithms, preloaded examples, what your scene might be and where your subject is.

With manual, the camera is in sync with your mind, it becomes part of you and so choosing and focusing on the subtleties is not a matter of 'throwing dice' but the realization of your creative vision.
05-01-2009, 12:03 AM   #12
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QuoteQuote:
julianactive: What are your opinions and experiences?
I try to shoot everything with manual focus and am always striving to better my techniques and skill. To me, a shot done with manual focus means much more to me because more of me made it. Anyone can push a button and take a picture. This is why I also enjoy manual mode, and using basic math skills to get a correct exposure rather than delegating that to the computer as well.

QuoteQuote:
julianactive: That sucker at full open has a depth of field as thin as a frog hair.
LOL, yes, when I first shot with that lens, especially with the original Pentax-supplied focus screen, I thought the same thing. But with the split prism and the excellent KPS magnifier, even f 1.4 is a treat to focus. Hang in there, you will get it down pat--and, please, post some images with that lens so I don't miss it anymore.
05-01-2009, 12:40 AM   #13
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The writer also use liveview. You wont be able to see that good in any optical viewfinder. The liveview is more accurate. He wont be manualfocusing with liveview in a hurry without a tripod with his 1kg lenses. If he do, he will have enough camerashake to make his focusing pointless.
05-01-2009, 02:31 AM   #14
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QuoteOriginally posted by julianactive Quote
Digital Photography

What are your opinions and experiences?
Nowadays there is multiple web sites for everything on earth. If you feel like exploring the pros and cons of manual focus there is a site called manualfocus.org

When it comes to critical focus, MF is still the preferred method - at least for me.

Some long discussion started with this

Manual Focus Forum / MF rules in case where AF would have been impossible



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05-01-2009, 02:36 AM   #15
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QuoteOriginally posted by flyer Quote
I'm not surprised. He used Canon and Nikon.

Both Canon and Nikon want to tell people that all you need to shoot a picture is to turn your camera towards the subject and press the shutter. And if you cannot take a better picture or you are not happy, upgrade your gear and not your skill.
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