iandiam
Member
So I have this GT that I've recently cleaned and relubed the shutter, and now i have it back together with a new POD and some cleaned up solder joints.
It seems to work okay, but upon developing the test roll of Fomapan 100, there is a definite problem with focus, but only wide open. Stopped down past f4, there does't seem to be a problem. I can't detect front or back focus, as the entire frame appears not to have any DOF, even in variable distance landscape shots.
Is there any collimation adjustment?
Is it possible that the baseline is off, and if so, is that fixable?
I'm fairly agile with the screwdrivers...
When I get back to the scanner later, I'll post some pics.
It seems to work okay, but upon developing the test roll of Fomapan 100, there is a definite problem with focus, but only wide open. Stopped down past f4, there does't seem to be a problem. I can't detect front or back focus, as the entire frame appears not to have any DOF, even in variable distance landscape shots.
Is there any collimation adjustment?
Is it possible that the baseline is off, and if so, is that fixable?
I'm fairly agile with the screwdrivers...
When I get back to the scanner later, I'll post some pics.
ColSebastianMoran
( IRL Richard Karash )
Ian, have you shot a picket fence or similar so you can see where your focus really is? And, do you have a way to check infinity focus?
If the focus is off, it's probably off at all apertures. You see it on wide-open shots because focus is more critical.
Of course, there are adjustments on this camera, but that isn't my area. I'm pretty good at running the tests.
Here's my focus test with a GX at about the close focus limit wide open. I find that 3 or 5 targets at two inch intervals is enough to see what's going on. Not sure you can tell in this screen image, but the center "200" is in better focus than the "800's."
If the focus is off, it's probably off at all apertures. You see it on wide-open shots because focus is more critical.
Of course, there are adjustments on this camera, but that isn't my area. I'm pretty good at running the tests.
Here's my focus test with a GX at about the close focus limit wide open. I find that 3 or 5 targets at two inch intervals is enough to see what's going on. Not sure you can tell in this screen image, but the center "200" is in better focus than the "800's."
iandiam
Member
I was focusing about 3 inches past the target. Initially, I replaced the POD. Having shot a roll thereafter, I noticed the focus issue, it was about 6 or more inches past target.
Since my last post I opened it back up, replaced the rangefinder with one from another, (as i have quite a few) and realigned, both from close-focus (.8m) and infinity, and was able to reduce the focus to less than a couple inches at close focus. Today, I tried with some ground glass. I'm not sure how this would be possible, but it seems like the lens was improperly adjusted. I've readjusted. Let's see how the next roll comes out. Fortunately I have plenty of cheap film around.
All I can figure out is that someone prior bought this and replaced the front element with one from a different production run or era; hopefully this will solve the problem. If the ground glass is any indication, it will.
Since my last post I opened it back up, replaced the rangefinder with one from another, (as i have quite a few) and realigned, both from close-focus (.8m) and infinity, and was able to reduce the focus to less than a couple inches at close focus. Today, I tried with some ground glass. I'm not sure how this would be possible, but it seems like the lens was improperly adjusted. I've readjusted. Let's see how the next roll comes out. Fortunately I have plenty of cheap film around.
All I can figure out is that someone prior bought this and replaced the front element with one from a different production run or era; hopefully this will solve the problem. If the ground glass is any indication, it will.