...POLL... Autofocus Fine-tune

...POLL... Autofocus Fine-tune


  • Total voters
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It only takes about 15 minutes from setting up the tripod to completion. I think many people are trying to over engineer the process.
I doubt if you could do it in 15 min. Multiply that by a bunch of lenses and 2 or 3 bodies and you have a weeks work. By the time you get it all done, you've upgraded your bodies.

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A Canon G5 and a bit of Nikon gear.
The trouble with normal is it always gets worse - Bruce Cockburn
I do it in 15 minutes all of the time. As to doing it with 2 or 3 bodies.... I perform the task when I purchase a new body or new super telephoto lens. It is an incremental job. Also, the technique permits me to test that something has not been knocked out by transport when I go to say Yellowstone. 15 minutes in the big pull off area just past the ranger gate as you enter from Montana and I know everything is working properly.

Read the results from the poll, real life targets and a realistic simple repeatable technique gets the job done.
Well in that case instead of saying "it only takes about 15 mins", why not say "here's what I do - it only takes 15 min"???
Because I was still responding within parameters set by the OP. He did not ask for step by step instructions, just merely which method from those list in his poll.

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A Canon G5 and a bit of Nikon gear.
The trouble with normal is it always gets worse - Bruce Cockburn
 
Thank you for your feedback everybody.Some very clever people here.



My reason for asking is my new camera is front focusing (a lot)I sent it off to Nikon for service when they received it they asked me if I can send samples which I deleted out of my computer(I didn't think they would ask for them) so they basically returned the camera to me without doing nothing to it.(Cost me $100.) So now it's gotta go back again but this time with samples and a software readout.



I only but two lens on the body so far the 24-70 (+17,18) and the 300 (+18) 300w/TC (+18+5 default). Both lens on the D800E were + - 3 so it's definitely the body.

My first attempt. Hopefully it's repeatable.

This is what I got out of the first part of the test on the 24-70 .On the second round (which I forgot to save) that Zero Line Accuracy # went up to 99%

I more upset about losing the camera for a few weeks than anything else.



Thanks again everybody...

eadb58e333674d2ab4936da371c0dd27.jpg.png



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It only takes about 15 minutes from setting up the tripod to completion. I think many people are trying to over engineer the process.
I doubt if you could do it in 15 min. Multiply that by a bunch of lenses and 2 or 3 bodies and you have a weeks work. By the time you get it all done, you've upgraded your bodies.
 
If only it was actually that easy.

You have to manually change the AF Micro-adjustment. It cannot do it automatically.

Enter menu, left left, ok, up one (or down), ok, take next picture then start again.
 
This is the worst part of getting a new camera. Just wondering how others go about this. I'm leaning towards giving FoCal a try.

Thank you for your input...
I use LensAlign with the Software, why do you have these separated this way? A nice, fairly simple, way to handle the process, and most software uses a standard target of some sort.
 
This is how I go about it:

HOW TO USE THE LENSALIGN SET-UP TO ALIGN YOUR CAMERA’S AUTO FOCUS FOR A PARTICULAR LENS

1) Set the camera to shoot monochrome images

2) Set the camera to either Manual Mode or Aperture Priority Mode

3) Set the camera to use only a single auto focus point in the center of the viewfinder

4) Set the camera to shoot only a single image when the shutter is pressed

5) Turn the camera’s Fine Tune setting to “Off” for your test shot

6) Set the aperture to F/8 for your test shot and in order to see if the LensAlign target is centered

7) Set the camera to shoot Large, Fine, JPEG images

8) Use a tripod and a cable release

9) Set the front of the camera body (not the front of the lens) at the correct distance from the front of the LensAlign target (actually, it is measured from the "sensor plane", which is usually

marked on top of the camera body. The D800 has it in white, next to the top LCD window as an

oblong circle with a line through it).

10) Make sure the LensAlign target is perfectly centered (view a test shot on your computer screen

to make sure-see 12, below)

11) Make sure the background, behind the LensAlign is black, or dark

12) Shoot a test shot to determine if the LensAlign target is correctly centered

13) If satisfied the LensAlign target is perfectly centered, change your aperture to its lowest number (i.e.; F/1.8 or 2.8, etc.- as long as your highlights are visible in the image; and not blown out)

14) Turn the camera’s Fine Tune setting back to “On” for your Fine Tune adjustment shots

15) Defocus the lens by manually moving the lens focus all the way to one side. Half-press the shutter to reacquire autofocus. Shoot an image; and look at it on the computer screen for accuracy of the “O” being in focus. The smaller numbers on the ruler give a better evaluation.

16) If necessary, go into the camera’s Fine Tune menu and adjust the focus point at various “+” or “-“settings. Defocus the lens, again; and re-shoot at those various new settings. After each test shot, re-evaluate the sharpness of the “O” on the LensAlign ruler. Keep adjusting your Fine Tune settings until the “O” on the LensAlign ruler is its sharpest.

17) Once properly adjusted, leave the camera’s Fine Tune setting “On”.

18) Go out; and take a few "field" shots; and evaluate them accuracy on your computer.
 
I believe Reikan FoCal Pro is that easy ,it's totally automated ,I bought it but it refused to load in my PC . Reikan told me it happens some times,that's why I went with FocusTune,that's definitely not automatic.
Reikan FoCal automatic mode is useless. It crashed so many times that I gave up on it. Now I just take a series of photos with different AF tuning values (usually -20, -18, -16, ... up to +20), then load them in FoCal manual mode. No more crashes, no more lost shots.
 
It is interesting how many choose not to read :(

Every Nikon body made in the last 15 years has come with a caution to the effect that, where there are objects at different distances within the AF detection area, AF may not not focus on what is in the centre of the viewfinder mark.

This is not the same as a general front or back focus issue and is why 45 degree or other angled targets may not always be reliable.

I do not disagree with careful alignment before starting the AF process angle targets may work well. I disagree with Nikon saying this type of target does not work; - with careful alignment it often can.

On the other hand if you are going to fine tune it seems wise to avoid all variables to ensure the result is not caused by a less than good for calibration target.

Nikon say in all fine tune camera instruction books fine tune is not normally needed.

There seems very little evidence by way of posted images showing an AF failure where the target is not a possible cause of poor focus accuracy.

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Leonard Shepherd
Is where you are in photography best defined by your recent photos or the equipment you own?
 
I've tried to check 30-700 VR, 17-55 f2.8, 12-24 f4. The last 2 are DX, but I just tested the approach.

With close-up filter (in this case Canon 500D, which is just 500 mm lens) your lens is already at infinity, while the testing target is only 500 mm away. Camera and lens 'do not know' any thing about the filter and work like target/subject is far away.

Since lens focus range looks like 'compressed', AF focus tuning is much more sensitive.

I can tune AF just switching between LV and normal mode.
When you focus using CDAF in LV, it takes proper focus right off of the sensor and nails focus, even if the lens needs fine tuning, right? I love this concept and use CDAF whenever I need pin point accuracy such as when shooting wide open or in low light/mixed light sources. It seems to work perfectly so far. Can anyone shoot this down? (CDAF = contrast detection auto focus, as opposed to phase detection auto focus - viewfinder type)
 
angled targets may not always be reliable
Never use angled targets.
Nikon say in all fine tune camera instruction books fine tune is not normally needed
That is just marketing speak.
There seems very little evidence by way of posted images showing an AF failure where the target is not a possible cause of poor focus accuracy.
I'm not sure I understand what you mean. With a good, flat, well-lit target, AF tuning definitely improves sharpness.
 
I've tried to check 30-700 VR, 17-55 f2.8, 12-24 f4. The last 2 are DX, but I just tested the approach.

With close-up filter (in this case Canon 500D, which is just 500 mm lens) your lens is already at infinity, while the testing target is only 500 mm away. Camera and lens 'do not know' any thing about the filter and work like target/subject is far away.

Since lens focus range looks like 'compressed', AF focus tuning is much more sensitive.

I can tune AF just switching between LV and normal mode.
When you focus using CDAF in LV, it takes proper focus right off of the sensor and nails focus, even if the lens needs fine tuning, right? I love this concept and use CDAF whenever I need pin point accuracy such as when shooting wide open or in low light/mixed light sources. It seems to work perfectly so far. Can anyone shoot this down? (CDAF = contrast detection auto focus, as opposed to phase detection auto focus - viewfinder type)

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Ernie Misner
http://www.flickr.com/photos/erniemisner/
Yes, you're right about CDAF.

During AF tuning I usually do CDAF (or in some cases just manual focusing) in order to know how 45 degree ruler looks like when focus is dead on the vertical target.

Then:

1. Switch back and focus using viewfinder

2. Switch to LV and zoom in. Look to the ruler

3. Apply appropriate correction and go to #1

4. Testing @ different focus and distance to the target (from closest to infinity)

Close up filter gives so shallow DOV, so any deviations easy to see.

And it's biggest advantage - ability to test @ infinity even big telephoto lenses.
 
It is interesting how many choose not to read :(
I hope your including your self.
This is not the same as a general front or back focus issue and is why 45 degree or other angled targets may not always be reliable.
Will you please show me where I said I am focusing on a angled target.Or where Nikon tells you to.

I disagree with Nikon saying this type of target does not work; - with careful alignment it often can.
Disagree all you like. I used a large (flat) Focustune supplied target.
Nikon say in all fine tune camera instruction books fine tune is not normally needed.
I had you in mind when I included #6 in the poll.

_There seems very little evidence by way of posted images showing an AF failure where the target is not a possible cause of poor focus accuracy.
I didn't post any images only a graph,here's another one from today with a +5 in the default. It show it's front focusing to. Nikon asked for images ,now I have some to send them. That's all.

b7b10f0b66b24ffba6101358a9b5b6ed.jpg.png

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http://www.flickr.com/photos/lickitysplit11111/
 
Nikon say in all fine tune camera instruction books fine tune is not normally needed.
Nikon also says that 105mm f/2.8 VR lens cannot AF with TC, but it can :-). That much for trust in Nikon's manuals.
 
I had recently posted this image on another forum. Shot this with my Nikon 300mm F/2.8, which is AF Fine Tuned at (-16) on my D600. Capture NX confirmed focus was acquired on the #9 horse's cheek. Now, without a whopping (-16) adjustment, I would get rather severe back focus. And this image has minimal sharpening applied.

As previous mentioned, I use Lens Align with great success.

Mike



7879335b531f4a5d8aaefd61b5d765a5.jpg
 
I had recently posted this image on another forum. Shot this with my Nikon 300mm F/2.8, which is AF Fine Tuned at (-16) on my D600. Capture NX confirmed focus was acquired on the #9 horse's cheek. Now, without a whopping (-16) adjustment, I would get rather severe back focus. And this image has minimal sharpening applied.



7879335b531f4a5d8aaefd61b5d765a5.jpg
Thanks for the image.

The horses eye, and the harness close to it, are less sharp than the face and hand of the rider, though some movement of the horses head may have occurred.

Are you trying to tell me you regard this as a sharp shot of the horses cheek?

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Leonard Shepherd
Is where you are in photography best defined by your recent photos or the equipment you own?
 

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