Originally posted by Kerusker Stan,
thanks for your efforts. I was/am hesitant to get involved in AF as there are soooo many aspects which may come into play.
Did you find Enzo's 'Quantitative Method' from Jan. 2012?
https://sites.google.com/site/vincenzomiceli/quantitative-micro-focus-adjustment-for-dslrs
Please give more information on your test set up (as already requested by others).
Also, did you find a lens which needs more than a +10 or -10 adjustment?
I just had a K-5 II for one week and did some kind of focus adjust comparison to my K-5.
My finding (with my method) was that both need very similar adjustment values (which may be shifted along the adjustment scale).
The Best
I haven't yet tried the Enzo's method - I was looking for something a bit more simple to try.
And yes, trying to get the AF right with a bunch of lenses can be exhausting, but I have now become kind of obsessed with it. I've become kind of disappointed with the K-5 in this respect as this is my second one which seems to have the AF system in the camera go out of alignment on its own. My K-5 is on its way back from CRIS - the work order shows that the camera was back focusing which they adjusted. Being this is my second time with this, I will have a hard time trusting it to stay put now. I guess I just don't understand why or how this can happen especially since I treat all my gear with kid gloves.
Anyway, here is a brief summary of the setup for taking the sample shots:
Print out the target provided by Focus Tune on 8.5x11 paper and hang on a wall. I put two of my continuous lights pointing at the target in hopes of a more accurate test.
Setup with a tripod - I was working mostly with my 300mm lenses, so the distance from the camera to the target was ~24'. There is a calculator on the website for distance between target and camera for various focal lengths.
Set the camera to jpeg, highest quality, single center point AF, fixed WB, SR off. Shoot the lens wide open.
Use the 2 second timer.
Then you start with taking 4 images at each AF adjustment value. You can start out using every other one, then to really fine tune you can select a range of the best from the graph and do a few at each AF adjustment value. So, I started out taking 4 shots each at AF adjustment 0,+2,+4,+6,+8,+10,-2,-4,-6,-8,-10. Between every shot you de-focus the lens slightly in the same direction each time. That is why I like this test as it makes the AF work for each image taken.
You will end up with 44 images. Then it is as simple as importing those images into Focus Tune, and hit one button, and the software does the rest. In about 30 seconds you end up with the .pdf graph like I displayed above.