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04-17-2011, 03:14 PM   #1
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Why are my m42 Super Tak pictures out of focus?

I get the confirmation beep from my k-x but the images, for the most part, are blurry. Nothing picture is crisp so it's not like I focused on a part of a shirt but not the face (I was doing outdoor portraits).

Some images were ok, none what I would call super crisp - but good images. Most pictures I take are out of focus. I do not have this problem with the kit lens AF. Is it me moving or something?

04-17-2011, 04:20 PM   #2
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With the M42 lenses, there is going to be some but overall little information to actually go on from the images EXIF data, so you are going to have to remember some of the information from shot to shot. You can pull the focal length of the lens out of the EXIF data - that will identify the lens, and that is a start. The aperture is not recorded for manual lenses - so if you could remember that will help.

On the images out of focus, I am going to guess that they were probably with your 50 and 55 more than the others. Also do you usually try to shoot wide open or stopped down? Wide open, you will have a very thin depth of field, so if someone leans a bit forward or backward (you or your subject), you might be out of focus. The cure for this is to stop down to something like f8 where your DoF will be larger. Take a look at this website...Guessing again that you probably have better luck on your wider lenses - 28 and 35 since these lenses are not as fast and the wider angle lenses have a better depth of field (just optics). I am also going to guess that with your longer lenses, the 135 and 200 you are also seeing some problems if your say less than 20 feet away, because the depth of field is all of 1 foot thick. Going to f8 doubles it, but its still pretty thin. At f11 its 3 feet, but then things may be getting a bit dark in the viewfinder, and light is going to be a concern if the subject is not out in strong daylight.

Do you have image stabilization (shake reduction) on? That may be another item to check.

You can use PhotoMe to look at the EXIF data. It records a lot, however with manual lenses, it does not receive any data from the lens on aperture.As far as the focus beep, I would ask if you confirmed the green focus "hex" symbol being lit in the viewfinder - the in-focus indicator. Down at the bottom of the PhotoMe window, there is a "find" box. Put in focus - and it will pull all the fields in the EXIF that have a focus description. If the camera thought that the image was in focus there is a field called AF points in Focus, and it will indicate which one. I just tested this on a image I had - fully manual lens, and it did list the field with Center (vertical) point used to report in focus. So this should provide you with some data. I am using a K20, so I think that your Kx would work in a similar fashion.

A few weeks ago, I was playing around with a new old manual lens. My AF lens would nail focus every time - bar none. Me and the manual lens, was - well lets just say close, but close was not close enough other than with horseshoes and nuclear weapons. I found I did better when I cleaned my eyeglasses. I am so farsighted that I can't see the smudges on them. It turned out to help some - but still practicing.

So, what I have been doing is 1) stopping down to f8 to get a deeper depth of field - i.e., a fatter target, 2) using SR or a tripod, 3) checking the green hex in the viewfinder, 4) relearning the long lost art of manual focusing, 5) thinking about a katzeye split focus screen - but I am not there yet on that one.

That is my 2 cents.....

Last edited by interested_observer; 04-17-2011 at 04:32 PM.
04-17-2011, 05:08 PM   #3
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Everything io said, especially final item (4) -- learn to focus manually. It takes practice, breath control, practice, movement control, practice, visual control, practice, patience, practice, some swearing, and lots more practice. With lenses with wide-enough bases, CIF (catch-in-focus) also helps a great deal.
04-17-2011, 05:11 PM   #4
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QuoteOriginally posted by RioRico Quote
It takes practice, breath control, practice, movement control,
Add Tai Chi and Yogic meditation to the list...

Seriously, though, post a shot you had the problem with and lets have a look.

Please also post info on what you intended to be in focus, what the focus point setting was, shutter speed, what focal length you set the shake reduction to (if you used it), how much coffee you had prior to the shot, etc.


Last edited by selar; 04-17-2011 at 05:23 PM.
04-17-2011, 05:47 PM   #5
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I think I posted too fast. I can see little pieces in focus behind the subject. But I would have never know except afterwards. It looks in focus on the viewfinder. Guess I should be glad I'm not spending money on film in 1969.

I don't understand why most AF lenses are in focus, however, I do the same composition and got the same AF confirmation beep with green hexagon. I know it's practice with manual but don't know why the auto gets it right.

edit: I was using the 50 1.4. I also messed up with the 135. But some were okay shots.
04-17-2011, 05:48 PM   #6
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QuoteOriginally posted by interested_observer Quote
A few weeks ago, I was playing around with a new old manual lens. My AF lens would nail focus every time - bar none. Me and the manual lens, was - well lets just say close, but close was not close enough other than with horseshoes and nuclear weapons. I found I did better when I cleaned my eyeglasses. I am so farsighted that I can't see the smudges on them. It turned out to help some - but still practicing.
This on the AF not the farsighted though...I think.
04-17-2011, 06:01 PM   #7
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I have astigmatism. I trust the AF beep more than I trust my eyes.
04-17-2011, 06:17 PM   #8
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here is one of the better ones:



04-17-2011, 06:42 PM   #9
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Focus point appears to be the forelock. Was this the 50/1.4 @ f1.4? Even the AF has trouble getting the focus point right with such a thin Depth of Field, so stop beating yourself up. If you really must use such a thin DOF, the only suggestion I can think of to help you, is to bracket focus. Just a hair turn each way should nail it.
04-18-2011, 12:02 AM   #10
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Using the focus indicator is a disaster!

It may well appear in the viewfinder that you're nicely focused when the indicator beeps, but - as you've found - the results are all over the place.

With my K-m, I find I get different manifestations of the problem according to FL. With a 135mm lens, the focus indication will seem very precise, but I'll be getting fairly repeatable (and often gross) front and back focusing (it varies with actual lens used). With a 28mm, the indication is really sloppy, and therefore useless. Only with a 50mm can I get reasonably good and consistent results.

Unfortunately, the only way to get good results is to focus manually, and this is easier said than done when you're using a DSLR focusing screen. Note that there are replacement screens available which are designed for manual focus, and come with focusing aids (like the old SLRs). However, there are issues with these - re-shimming may be necessary, and metering may be affected.

Unless you've identified some lenses which work well with focus-confirmation, don't do it!
04-18-2011, 05:55 AM   #11
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QuoteOriginally posted by selar Quote
Focus point appears to be the forelock. Was this the 50/1.4 @ f1.4? Even the AF has trouble getting the focus point right with such a thin Depth of Field, so stop beating yourself up. If you really must use such a thin DOF, the only suggestion I can think of to help you, is to bracket focus. Just a hair turn each way should nail it.
I guess maybe af points would be helpful? the k-r has them by k-x does not.
04-18-2011, 06:18 AM   #12
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Does not make a difference if you just use center focus.
04-18-2011, 01:54 PM   #13
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QuoteOriginally posted by justtakingpics Quote
I guess maybe af points would be helpful? the k-r has them by k-x does not.
The Kx does have them, You have to select them in the rear lcd. But agree, not relevant in this example.
04-18-2011, 06:55 PM   #14
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Then I don't understand what the problem is if AF points won't help.
04-18-2011, 07:09 PM   #15
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QuoteOriginally posted by m42man Quote
Using the focus indicator is a disaster!

It may well appear in the viewfinder that you're nicely focused when the indicator beeps, but - as you've found - the results are all over the place.
I second that.
AF confirm is useless with MF lenses(far to much play) and accuracy degrades as total aperture size increases(f/2 or less).

Best thing to do is use LV and magnify to focus.
Or... if you prefer VF, insist in a split prism focusing screen.

Last edited by JohnBee; 04-19-2011 at 03:44 AM.
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