AF Micro-adjust

[gramps]

Using a test card, is it recommended to have a distance of 25 or 50 times the focal length of the lens between the camera and card ... or is it something different?

 

[Whippet]

Yup 25-50x

 

[Whippet]

https://dl.dropboxusercontent.com/u/11469157/FoCal/Docs/FoCal Test Distance_1.0.pdf

The above are the distances recommended by FoCal for their automated software driven AFMA but the same would be true for doing it manually

 

[Gaz J]

I use 25 times gramps and have found that ok. But i dont use focal or lenscal or anything like that because I dont think they are worth the money.

There is a school of thought that you should calibrate them at the distance you use them most often.

 

[gramps]

I've tried Focal and it just didn't work for me, I do have a Lenscal which I plan to use ... in practical terms, with an 800mm lens, distance can be an issue

 

[OldCarlos]

There is a school of thought that you should calibrate them at the distance you use them most often.

I agree with that ESPECIALLY with a zoom lens.

 

[Pistnbroke]

With an 800mm I would go with the take a photo of a feature of "the house over the road" or a car number plate and do a series of -20 to +20 going in 5 steps this will put you in the ball park for a fine tune.