AVS Forum banner
Status
Not open for further replies.
1 - 5 of 5 Posts

·
Registered
Joined
·
254 Posts
Discussion Starter · #1 ·
When I set up my G70 the inner focus rings all have to be turned to the maximum toward the right and seem to be focussed. The outer focus rings are about centered in the range of motion. I have been satisfied enough to just leave it for that past few months but now I am going to ceiling mount it so I want to get it the best it can be. The manuals seem to leave out the part about different sized shims for each lens. What should I do (if anything) to get the best focus somewhere around the middle of the range of motion?


Chuck Anstey
 

·
Registered
Joined
·
2,293 Posts
You don't say what your screen size is, or your throw distance. If the center focus (the adjustment closer to the projector chassis) is all the way to the stop, it sounds like you are at either the minimum or maximum distance.


There are no shims to adjust; this projector has continuous Schiempflug focus adjustment done with small knobs that turn large ring gears. I would have thought that this should have been in the manual.


William
 

·
Registered
Joined
·
254 Posts
Discussion Starter · #3 ·
I am projecting 90" wide screen at the correct distance according to PJCalc. I have tried moving forward and backward by over a foot with the same result. No matter where I move the projector, the best center focus is found with the rings farthest away from the projector turned all the way to the right. The Schiempflug adjustment is for top/bottom or left/right edge focus right? I am talking about the dead center focus of the screen. I remember reading somewhere in a Sony manual on the net(can't find it now) that for really small or really large screens the lenses themselves had to be shimmed with a different thickness face plate to move it closer or farther away from the CRT face to allow correct focus in addition to moving it to the correct distance. I was wondering if I might have the wrong size on it now since it was bought used.


Chuck Anstey
 

·
Registered
Joined
·
2,293 Posts
The focus adjustment further from the projector is EDGE focus, not center. This usually is near the limit but not normally at it. The adjustment closer to the projector chassis is the center focus. I'm not sure, but from your description it sounds like you might have this backward...


William
 

·
Registered
Joined
·
254 Posts
Discussion Starter · #5 ·
I sure do have it backwards, just checked the manual. Oh well back to the drawing board on this one. It's funny that it seems to have the exact opposite affect when working with them. The G1 screw seems to affect the outer edge focus much more than the G2 screw, which seems to affect the center focus more. Thanks for making me RTFM again.


Chuck Anstey
 
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Status
Not open for further replies.
Top