lens align, trials & tribulations

[adrian tyler]

hi,
i've been using lens align to set up my d800
the nikon 35 1.4g sets up at -15
however when i focus in infinity (20km), it'll front focus to about 25m, well out of foucus if shooting wide...
if i switch off the "af focus adjust" on the camera it's a lot better, not bang on, but not far off it
anyone else seen this behavior?
thanks
http://www.adriantyler.net/

[kers]

From my experience ( nikon d800+ 1,4 24mm et al)  these focus problems- especially with wide angles with subject at a distance and wide open- are not easy to tackle.
If so Nikon- or canon should have done already.   Also in low light things get more complicated. I have not adjusted any focus yet because at the moment i do not find any clear pattern. I try to use live view as much as i can.
On the other hand telelenses perform very well- the 70-200 is really fast and accurat...

[MarkL]

What distance did you use when using lensalign?

I used FoCal to do mine and had no issues and it didn't come back with an real variation with distance. None of my lenses are wider than 50mm though.

In the absence of good manufacturing tolerances, what we need is sigma's new tech:

[Ellis Vener]

hi,
i've been using lens align to set up my d800
the nikon 35 1.4g sets up at -15
however when i focus in infinity (20km), it'll front focus to about 25m, well out of foucus if shooting wide...
if i switch off the "af focus adjust" on the camera it's a lot better, not bang on, but not far off it
anyone else seen this behavior?
thanks
http://www.adriantyler.net/

What is your target to camera distance? 25x focal length, 50x focal length or something different?

Also if focusing on an object that is 20km away with a 35mm lens how can you tell that it is front focusing by 20 meters?

[adrian tyler]

What is your target to camera distance? 25x focal length, 50x focal length or something different?

Also if focusing on an object that is 20km away with a 35mm lens how can you tell that it is front focusing by 20 meters?

hi, my target distance was 25x, which i found quite difficult enough to assess accurately...
sorry if i am missleading you, the focus is on infinity and the camera (whith the adjustment feature on) focuses to about 20m (not 20m from infinity...), here is an example of the scene: