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05-23-2016, 11:36 PM   #1
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AF fine adjustment without the trouble

Has anyone done af fine adjustment on the fly without having to go through all the "trouble".
Maybe +1 or -1 just to see how it affects the focus or is all the trouble a COMPLETE must?

05-23-2016, 11:50 PM   #2
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Absolutely complete must.

Easier to get it wrong than right and doing it on the fly is just random chance.

But who knows there are only 20 or so settings, you might get lucky.
05-23-2016, 11:51 PM   #3
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QuoteOriginally posted by Culture Quote
Has anyone done af fine adjustment on the fly without having to go through all the "trouble".
Maybe +1 or -1 just to see how it affects the focus or is all the trouble a COMPLETE must?
"All the trouble" is a complete must IMO. You're talking about micro-adjustments, after all. To apply the proper corrections and reach a definitive conclusion, a controlled setup is necessary.

If you're not having any issues with your lens, just leave the adjustment setting alone. Unless you're working with a very shallow DOF chances are that a small inaccuracy will have no practical effect.

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05-24-2016, 12:53 AM   #4
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QuoteOriginally posted by Culture Quote
Has anyone done af fine adjustment on the fly without having to go through all the "trouble".
Maybe +1 or -1 just to see how it affects the focus or is all the trouble a COMPLETE must?
It only takes a couple of minutes to fire off a series of shots at infinity and different AF adjust settings (step by 2 or 3 first to narrow down the range quickly) and then to pick the best setting for your body/lens combination. You don't need fancy targets etc. and it will make a significant difference to the reliability of your autofocus.

05-24-2016, 02:19 AM   #5
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PM me I will guide you with the proces and focus targets settings
05-24-2016, 03:12 AM   #6
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I just hope other manufacturers will copy Nikon's automatic approach soon and all this trouble will be in the past.
05-24-2016, 07:21 AM   #7
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QuoteOriginally posted by kh1234567890 Quote
It only takes a couple of minutes to fire off a series of shots at infinity and different AF adjust settings (step by 2 or 3 first to narrow down the range quickly) and then to pick the best setting for your body/lens combination. You don't need fancy targets etc. and it will make a significant difference to the reliability of your autofocus.
Infinity isn't the recommended distance for AF fine adjustment typically. I'm surprised by this advice but have to admit I haven't compared recommended methods to this.
05-24-2016, 09:47 AM   #8
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Well, infitnity is the only more or less defined distance setting on your camera. So setting up a proper infinit position is already quite useful.
What AF adjustment is really about is DOF control plus positioning optimum sharpness. So you need to find a distance long enough that close range effects have no influence but far enough to judge DOF in the image/target. This cannot be done on the fly. It takes time and patience as well as a tripod and a useful target. If you want to do it on the fly, it will fail!

05-24-2016, 09:49 AM   #9
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QuoteOriginally posted by UncleVanya Quote
Infinity isn't the recommended distance for AF fine adjustment typically. I'm surprised by this advice but have to admit I haven't compared recommended methods to this.
Infinity has always worked best for me, with all AF lenses - check my Flickr stream
05-24-2016, 09:56 AM   #10
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I usually use LensAlign Distance Tool to set proper distance for various lenses
05-24-2016, 11:37 AM   #11
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AF adjustment easy ? You don't have to understand anything.
1) Take one target with fine details, for example a book with some text written small at a distance, or a newspaper, set the lens aperture to maximum (smaller f number).
2) Take one photos with 0 adjust
3) Take another photo with +1 adjust
4) Take another photo with -1 adjust
5) Take another photo with +2 adjust
6) Take another photo with -2 adjust
7) Take another photo with +3 adjust
8) Take another photo with -3 adjust
9) Take another photo with +4 adjust
10) Take another photo with -4 adjust
etc...

Compare images at 100% zoomed, use the setting that give the best image sharpness.
05-24-2016, 02:06 PM   #12
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If you want to get an highly accurate focus adjustment, you DO need to go through the hassle. Definitely use a low ISO and tripod to get the clearest, sharpest images you can. High ISO or hand holding the camera can soften the image enough that you won't see the minute focus differences as easily.

That being said, if you're getting consistent front or back focusing in the field, it can't hurt to try some adjustments. Just take multiple shots to confirm. (Don't consider it 'correct' based off of one well focused picture!)

Some lenses also require a different adjustment at different ends of their zoom ranges. I've found that certain lighting situations and subject distances can trick the auto focus too.

I have a K-3 and Tamron 17-50 f/2.8 combo that works great on subjects 5-150 feet away with an adjustment of +1. However, one somewhat dimly lit room of my house with a 'warm white' LED ceiling fixture causes the same combo to front focus, so I have to dial in -3 for subjects from 5-15ft. This is even worse when the subject is within 3ft, and I have to dial in -8 or so. When I first noticed all my pictures were severely front focused I didn't have time to set up a target and go through the whole adjustment process. I roughly adjusted it through about 15 frames of trial and error after which I shot a decent amount of keepers. (Previously I'd had none.) On going back to regular lighting everything was severely back focused until I returned the adjustment to +1 and it works great again.

(Now that I think about it, I'll have to go back and fine tune the settings for that room so I know right where to set it to next time I take pictures there.)

Last edited by TheOneAndOnlyJH; 05-24-2016 at 02:11 PM.
05-24-2016, 07:17 PM   #13
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My experience with AF fine tuning. I have a K3 & K5iis, and Sigma 70-200 f2.8. Both cameras set to max adjustment for this lens. Enter daughter with a new K3ii. We are shooting surfers side by side, K3 with DA*300, daughters new K3ii using said Sigma. K3ii & Sigma were having focus issues, we swapped lenses, no more issues. So, took a guess and set the AF fine tune on K3ii to the same as K3. (Remember we were out shooting)......no more issues, the K3ii churning out tack sharp images. Also checked the setting for the DA300.....it was 0....which was why it was sharp straight up on the K3ii.
So.....is it worth an hour of your time to set up a little test ?. Absolutely.
05-24-2016, 10:20 PM   #14
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QuoteOriginally posted by biz-engineer Quote
AF adjustment easy ? You don't have to understand anything.
1) Take one target with fine details, for example a book with some text written small at a distance, or a newspaper, set the lens aperture to maximum (smaller f number).
2) Take one photos with 0 adjust
3) Take another photo with +1 adjust
4) Take another photo with -1 adjust
5) Take another photo with +2 adjust
6) Take another photo with -2 adjust
7) Take another photo with +3 adjust
8) Take another photo with -3 adjust
9) Take another photo with +4 adjust
10) Take another photo with -4 adjust
etc...

Compare images at 100% zoomed, use the setting that give the best image sharpness.
This is more like what I was looking for. Thank you very much.

---------- Post added 25-05-16 at 08:21 ----------

QuoteOriginally posted by TheOneAndOnlyJH Quote
If you want to get an highly accurate focus adjustment, you DO need to go through the hassle. Definitely use a low ISO and tripod to get the clearest, sharpest images you can. High ISO or hand holding the camera can soften the image enough that you won't see the minute focus differences as easily.

That being said, if you're getting consistent front or back focusing in the field, it can't hurt to try some adjustments. Just take multiple shots to confirm. (Don't consider it 'correct' based off of one well focused picture!)

Some lenses also require a different adjustment at different ends of their zoom ranges. I've found that certain lighting situations and subject distances can trick the auto focus too.

I have a K-3 and Tamron 17-50 f/2.8 combo that works great on subjects 5-150 feet away with an adjustment of +1. However, one somewhat dimly lit room of my house with a 'warm white' LED ceiling fixture causes the same combo to front focus, so I have to dial in -3 for subjects from 5-15ft. This is even worse when the subject is within 3ft, and I have to dial in -8 or so. When I first noticed all my pictures were severely front focused I didn't have time to set up a target and go through the whole adjustment process. I roughly adjusted it through about 15 frames of trial and error after which I shot a decent amount of keepers. (Previously I'd had none.) On going back to regular lighting everything was severely back focused until I returned the adjustment to +1 and it works great again.

(Now that I think about it, I'll have to go back and fine tune the settings for that room so I know right where to set it to next time I take pictures there.)

I never thought about the low ISO part, but it does make sense. Thanks.

---------- Post added 25-05-16 at 08:27 ----------

QuoteOriginally posted by Adam Quote
"All the trouble" is a complete must IMO. You're talking about micro-adjustments, after all. To apply the proper corrections and reach a definitive conclusion, a controlled setup is necessary.

If you're not having any issues with your lens, just leave the adjustment setting alone. Unless you're working with a very shallow DOF chances are that a small inaccuracy will have no practical effect.
It seems like the complete must is the general concensus. But the task is daunting for me.

My tamron 28-75 2.8 seem soft for my liking compared to its big brother 70-200 2.8. I am wondering if its front focusing
I just want something simple to test my suspicion.


Thank everyone for the advice.
05-25-2016, 12:44 AM   #15
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QuoteOriginally posted by Culture Quote
My tamron 28-75 2.8 seem soft for my liking compared to its big brother 70-200 2.8. I am wondering if its front focusing
Focus manually using live view with magnification, or use live view AF. If it produces a sharp result (compared to what you're used to), then you may have a PDAF issue.

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