View Full Version : Back flange adjustment question . . .


Ian Campbell
April 19th, 2008, 09:28 PM
Can someone suggest the best way to do a back focus set up? Here's the problem . . . I, like so many others, am having focus issues with my Z7U cameras.

If the camera is approx. 10 ft. from the pattern, much of the room is clearly in view on the monitor for the second part of the setup when the lens goes as wide as possible to calibrate. Will what is in view (other than the chart) affect the set up? In the house and office when the lens is at its widest you can see other things in the room (some further from the chart, others closer). I had to go outside to use the garage door (with chart taped to door) to have the least clutter around the chart. Even this wasn't perfect since the sides of the garage and some brick were in frame when the lens went to its widest.

Does the camera truly (when calibrating the wide part of the setup) use only the center of frame as reference?

Any thoughts would be helpful.

Thanks!

Ian

Christopher Young
April 21st, 2008, 12:42 AM
Can someone suggest the best way to do a back focus set up? Here's the problem . . . I, like so many others, am having focus issues with my Z7U cameras.
Ian

Being used to years of manually back-focusing cameras I still do it that way, even with these small cameras. I would suggest setting the back-focus manually as per the manual instructions on page 11 of the manual. Doing it that way you can concentrate on the star chart and the camera won't be influenced by the surrounding brickwork etc. To help doing it manually turn on your 'Peaking' in the 'Display Set' menu and use the L2 'Extended Focus' function.

Chris Young
CYV Productions
Sydney, Aust

Arnaud Keil
April 21st, 2008, 01:01 PM
Being used to years of manually back-focusing cameras I still do it that way, even with these small cameras. I would suggest setting the back-focus manually as per the manual instructions on page 11 of the manual. Doing it that way you can concentrate on the star chart and the camera won't be influenced by the surrounding brickwork etc. To help doing it manually turn on your 'Peaking' in the 'Display Set' menu and use the L2 'Extended Focus' function.

Chris Young
CYV Productions
Sydney, Aust

Hi Chris, maybe that you don't own a Z7, but I've found that it's nearly impossible do to an accurate manual back focus without a real back focus ring we can find on pro lenses.
When zooming out, nearly all the picture is in focus, at 10 ft or less we're near from hyperfocal... I would like to know how Sony do for focusing on the chart at the widest focal lenght.