How to adjust AF

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May 11, 2006
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Randy
After shooting the Z6 I realize my DSLRs (D500, D850 and D5) need fine tune adjustment on my lenses. The z6's accuracy on AF is rather startling coming from DSLRs.
I'll probably start w/ a 500e and 500pf.

So what method do you prefer, I'm looking for easy and it works

thanks
 
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You will find many methods. Isimply took pictures of a shorebird (or sometimes a small stuffed animal) on the beach at different adjustments. I had no trouble telling which ones had the sand right under the bird in best focus.
 

Butlerkid

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I started fine tuning my lenses many years ago. It does indeed often make a big difference! LOL~

I have used both the Nikon AF Fine Tune system which Glenn's recommended in his post, and the Lens Align Tool. In my experience, the results from Nikon's AFFT process were extremely close to the results I got using the Lens Align tool.

I recommend using the Nikon AFFT first - and see if you like the results.
 
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Randy, for years you touted that you never needed to fine tune your lenses. Interesting that your new Z6 has made you explore this for your DSLRs.

I've done all my long lenses with FoCal software. Works well but is a bit tedious. You do get some interesting lens information. Unfortunately it doesn't work well for zooms. If I hadn't already purchased the software, I would try the dot-tune technique with a ruler.
 
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Go out in your back yard and place a cereal box in the grass. Focus on the box. The grass before and after the box should be symmetric. If not adjust aft accordingly. This is the trenchmonkey method and has always worked for me. Often times I will use a stick on asphalt pavement to check things in the field. Should take no more than 5 minutes. It's about time buddy, welcome to the club. Check your 400 2.8 wide open. :D
Edit: forgot to mention but you probably know this, perform this test wide open.
 
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I also used Focal for years, worked well but was cumbersome.
There was a method published years ago that sounds crazy- but it works and is easy. I can not find the original posts to give credit.
Basically you lock your camera down and confirm sharp focus in live view, manually focusing on a chart or something with really good contrast.
Without moving anything, switch the lens to auto focus- but do not change focus. Look through the viewfinder, the in focus light should be solid. Then go to the af fine tune menu. I will assume it is at zero. Put it at +1 and hit enter, is the auto focus light still solid? Then +2, etc until the auto focus light starts to flicker at all- or goes off. Write down that number, lets say +4. Then go the other direction, -1, -2 until the focus light starts to flicker or goes off again. Lets say that is at -8. Average the two values together. -2 would be your final value. Whole thing takes about 2minutes, and my results were very very close to focal- which took a lot longer. Give it a try. Again, not my idea but I can not find the original write up.
By the way, I agree the mirrorless cameras just seem to focus better- when they achieve focus it is really sharp.
Gary
 

Butlerkid

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I also used Focal for years, worked well but was cumbersome.
There was a method published years ago that sounds crazy- but it works and is easy. I can not find the original posts to give credit.
Basically you lock your camera down and confirm sharp focus in live view, manually focusing on a chart or something with really good contrast.
Without moving anything, switch the lens to auto focus- but do not change focus. Look through the viewfinder, the in focus light should be solid. Then go to the af fine tune menu. I will assume it is at zero. Put it at +1 and hit enter, is the auto focus light still solid? Then +2, etc until the auto focus light starts to flicker at all- or goes off. Write down that number, lets say +4. Then go the other direction, -1, -2 until the focus light starts to flicker or goes off again. Lets say that is at -8. Average the two values together. -2 would be your final value. Whole thing takes about 2minutes, and my results were very very close to focal- which took a lot longer. Give it a try. Again, not my idea but I can not find the original write up.
By the way, I agree the mirrorless cameras just seem to focus better- when they achieve focus it is really sharp.
Gary
You can "shorten" the process by adjusting the settings by 5 and then going to 1 step increments once a 5 step increment The Dot Tune method described in detail on FM.
 
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I also used Focal for years, worked well but was cumbersome.
There was a method published years ago that sounds crazy- but it works and is easy. I can not find the original posts to give credit.
Basically you lock your camera down and confirm sharp focus in live view, manually focusing on a chart or something with really good contrast.
Without moving anything, switch the lens to auto focus- but do not change focus. Look through the viewfinder, the in focus light should be solid. Then go to the af fine tune menu. I will assume it is at zero. Put it at +1 and hit enter, is the auto focus light still solid? Then +2, etc until the auto focus light starts to flicker at all- or goes off. Write down that number, lets say +4. Then go the other direction, -1, -2 until the focus light starts to flicker or goes off again. Lets say that is at -8. Average the two values together. -2 would be your final value. Whole thing takes about 2minutes, and my results were very very close to focal- which took a lot longer. Give it a try. Again, not my idea but I can not find the original write up.
By the way, I agree the mirrorless cameras just seem to focus better- when they achieve focus it is really sharp.
Gary
DOT-TUNE
 
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Dot tune, that was it. I could not remember the actual name, and my google skills obviously leave some to be desired.
Anyway, it is quick and it works. I didn't find skipping 5 to save that much time, my numbers were usually not real high, maybe I was just lucky.
Gary
 
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After some surprisingly soft photos, I thought I might need to adjust my lenses' focus. Being lazy, I soon decided that the patterned cotton curtains would do for a real-world test. Backing off to the maximum distance available, (the width of a room + hallway) which is a good average working distance for me, I took a series of photos with all of my lenses. I was surprised and happy to discover I could see not only the pattern, but the needle holes in the material, And the weave of the cloth, too! Close enough for me! :D
 
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Dot tune, that was it. I could not remember the actual name, and my google skills obviously leave some to be desired.
Anyway, it is quick and it works. I didn't find skipping 5 to save that much time, my numbers were usually not real high, maybe I was just lucky.
Gary

Dot tune is the correct name, and just to give credit where credit is due, I think Snapsy on Fred Miranda's site was the first one to publish it. I have the orginal text of his post somewhere if someone needs it; it explains it simply and in detail. If someone wants it, l can PM it to them.
 
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You need a longer telephoto!
Seriously, the older we get, the better our cameras seem to focus!
Not hardly..I have trouble enough focusing my 70-300 on my DX camera, even with Nikon's whiz-bang 4 1/2 stop VR helping!

Uh Huh...I've noticed that! :wideyed: Nowadays, it seems I can farble the focus/sharpness even with my camera's great AF! Mostly photog caused camera movement. Whole lotta shakin' going on!:arghh:
 
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vancouver, canada
Hi Randy,

I use Reiken FoCal for adjusting my lenses as it warms my obsessive compulsive heart. It is accurate and also gives good data on the focus adjustment and on things like Autofocus repeatability and the sharpest aperture for a particular lens.

But, this program is overkill for most people. The methods above all work. A simple method is photographing a high contrast target at a number of different focus shift settings and then find the sharpest shot and that is your focus adjustment. I shoot at -20, -10, 0, +10 and +20 then pick out the one that seems the best and then shoot around this number by 2s ( if +10 then i would shoot +4, +6, ++8, +12, +14) then go from there. In practice it is very hard to see a difference of +- 1.

Things to watch out for.

1. Adjust at a distance where you use the lens most.
2. Make sure the target is at least 5 to 10 times the focal length away for accuracy of adjustment
3. use a very high contrast target. You can print the target on a printer. (i print the focal target on my Pro1000.
4. Shoot with lots of light and make sure the air is still. Thermals off the ground or pavement will mess up the shot. Steve Perry has a video on this.

Good luck,

Alexis and Georgie Beagle

" focus adjustment is like sharpening a knife... it just works better when sharpened." - Georgie Beagle
 
Joined
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DFW, TX.
Like many have already referenced, I've used FoCal & DotTune method for quite some time with DSLR's. Both work quite well and offer comparable result. One is automated & is an app that runs on a PC or MAC. The other is free.

Target distance and light quality are both very important to the results. If you're lucky enough to have a very large indoor area that you can tune a 500 / 600 mm lens (with & w/o TC's), just be sure you have light that is bright and does not flicker. Even some LEDs have flicker & that will impact the results.

All that said, I am surprised you feel the need to focus tune the Z body.

Perhaps, I'm accepting really good as "good enough" (could it be even better?) on my Z Bodies. I currently have a Z6 & Z50 and my wife also has a Z50. All three work perfectly with all of our lenses (Adapted & native), both with and w/o TC's.

Are folks finding their Z bodies actually need AFFT?
 
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