That appears to be different behaviour to the "official" HQ lenses" I have - the main mounting ring does not have to be released. It's some time since I last used the HQ/GS cameras but, IIRC, I "think" I initially install with the Near/Far ring set at (max) Far ie. no ring is regarded as a "back focus ring". However, IIRC, C or CS camera lenses have a different back focus length (at infinity) hence the need for an appropriate fixed size adapter between the main sensor mount and the lens. Of course "infinity" for these type of sensors/lenses is not that far metres cf. 10's of metres for 35mm equivalent cameras sensorsTrevor,
Can I just try to clear up one point.
When I refer to Back Focal length I am referring to the Camera Back Focus ring. The recommendations I have read indicate that this should be "screwed in fully", however, if you do this and then try to adjust the Lens Focus ring.. you can only do it in one direction FAR, as the NEAR option will not move as it is securely fixed into the Camera.....
So what I have been doing is unscrewing the Back Focus ring to get both Near and Far adjustment on the Lens Focus ring, but to do this you must unscrew the Back Focus ring and lock back it in place first before you try to adjust the Lens Focus ring, then you can try to adjust the Far adjustment, the Near Adjustment will still not work because the Back focus ring is locked, however, if you unlock the Back Focus ring you will get the option to move the Lens Near Focus, which will also move the Back Focus closer to the Camera Lens.... it's all a bit too fiddly and reliable results I get are very time-consuming to achieve.....
Hope you can understand what I am trying to explain here?
JohnW
Trev.
Statistics: Posted by FTrevorGowen — Mon Dec 02, 2024 1:50 pm