01-01-2017, 08:23 PM
Folks this is new year come on let's be peaceful.
I think you are close to an agreement.
We usually align the focus screen to the sensor not to a specific lens, here's another presentation of the SLR light paths
![[Image: slr-light-paths.jpg]](http://graphics.stanford.edu/courses/cs178/applets/slr-light-paths.jpg)
a camera will have front back focus with all lenses if AF sensor and image sensor are not aligned, the image is in sharp focus on the AF sensor but not necessarily on the imaging sensor, with alignment the camera will have accurate autofocus, why this shouldn't apply to the focusing screen ?
Thanks to advances in manufacturing process this is very rare to happen, normally all three are aligned, however when they aren't you can realign them.
I think you are close to an agreement.
We usually align the focus screen to the sensor not to a specific lens, here's another presentation of the SLR light paths
a camera will have front back focus with all lenses if AF sensor and image sensor are not aligned, the image is in sharp focus on the AF sensor but not necessarily on the imaging sensor, with alignment the camera will have accurate autofocus, why this shouldn't apply to the focusing screen ?
Thanks to advances in manufacturing process this is very rare to happen, normally all three are aligned, however when they aren't you can realign them.