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# Thread: Looking for guidance on focusing issue with Mamiya RB67 ProS

1. Hi Graham,

clicking on the attached lion shot and resizing it to full size on my computer screen it is clear that your field of acceptable focus extends from the back of the fountain (behind the lions) to infinity. Everything from the lions and closer is out of focus. So obviously the bellows were not extended far enough.

This may be a stupid question but you do realize that you need to extend the bellows to focus on things that are closer than infinity, right? I ask that because you said you "always found that the best focus was with the bellows right up against the camera body".

Having the bellows totally closed means that the lens will be focused at infinity. You will get some things closer than infinity in focus depending on the size of the aperture and the focal length of the lens, but the plane of critical focus will be infinity. So if you want to take a picture of those lions you need to extend the bellows to move the plane of focus to the lions. Did you use the rangefinder spot on the lions, or on a line that was far away, at infinity? If you lined up something at infinity then everything is working fine with your camera. If you used the rangefinder on the lions themselves then it is a camera issue.

Apologies if you knew all that already - it just seemed from your post that maybe you were unsure.

2. Originally Posted by nwilkins
Hi Graham,

clicking on the attached lion shot and resizing it to full size on my computer screen it is clear that your field of acceptable focus extends from the back of the fountain (behind the lions) to infinity. Everything from the lions and closer is out of focus. So obviously the bellows were not extended far enough.

This may be a stupid question but you do realize that you need to extend the bellows to focus on things that are closer than infinity, right? I ask that because you said you "always found that the best focus was with the bellows right up against the camera body".

Having the bellows totally closed means that the lens will be focused at infinity. You will get some things closer than infinity in focus depending on the size of the aperture and the focal length of the lens, but the plane of critical focus will be infinity. So if you want to take a picture of those lions you need to extend the bellows to move the plane of focus to the lions. Did you use the rangefinder spot on the lions, or on a line that was far away, at infinity? If you lined up something at infinity then everything is working fine with your camera. If you used the rangefinder on the lions themselves then it is a camera issue.

Apologies if you knew all that already - it just seemed from your post that maybe you were unsure.
No apologies necessary because, in fact, I had not extended the bellows and I was unsure. I don't recall exactly if the center spot was on the lions or behind them. I was more or less eyeballing it through the prism. Sometimes it is difficult to find any lines to use for focusing. I was using the 65mm lens, and I am also realizing now that I hadn't adjusted the FLE to the right distance. I'm going to go out and shoot another roll and see how I do.

3. okay well that's great then - if the bellows weren't extended at all on the lion shot then your camera is working correctly!

Try and use the rangefinder to find a line on whatever it is you need to focus on, or try eyeballing it - I actually find it easiest to focus using the centre spot of the plain matte screen. And I use the chimney finder, which is easier to use than the WLF (higher magnification and more light is blocked out). If using the WLF definitely employ the flip up magnifier for focusing.

4. That's good to hear. I have both a CDS prism and a chimney finder.

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