Posted by Dennis Lee on January 11, 2001 at 22:54:46:
In Reply to: Re: Polariod back for Century Graphic (6x9) posted by Dongyun Hao on January 11, 2001 at 18:58:46:Hi Dongyun,
Oh how I hate to hear your comments about there being a difference in the GG and film plane with the Horseman back. I've been having so many problems with sharpness it's unbelievable. My current theory is a poor lens. See the comments about the Xenar 4.5 below in this forum.
Here's where I'm at: I purchased a Horseman back after much frustration with a Graflex RH8.
I found that the back fits but extremely tightly. If I make sure the back is centered properly on the camera, groove to groove that is, I press in on the back a little bit and with fingers from both hands push in on both ends of the locking bar. I do the top and then the bottom. I had a few problems at first but now it is starting to fit quite nicely.
I have a Black Century Graphic by the way.
I do remember that alignment was very critical the first several times that I put the back on. It was also difficult to keep from moving the camera because of the tightness of the fit. After a few rolls now, and a lot of on and off, it's mounting much easier.
I don't have a caliper of any quality, it's plastic, but it did
measure a match on my camera.
Not trusting this I removed the GG from its holder and shuttled it
between the two film plane surfaces and got a perfect match. IE: I
focused on the ground glass in its normal position and then placed
the ground glass against the film plane in the Horseman back. I
checked the focus several times using my Leica 50 as the loupe and
the match came up excellent each time.
In testing the back with film I noticed a definate improvement over the RH8, same lens position, just switching the back, using Fuji Velvia. The Horseman was definately sharper but overall quality is still borderline unacceptable for what this negative size should produce. As mentioned earlier, I think I have a poor lens.
The one problem I do have with the Horseman back is that the actual film window is being vignetted by the metal edge of the rear bellow frame in the camera. This makes one of the vertical edges soft on the frame. Not good for printing full frame.
Obviously I'm using the 6x9 back. I should also note the the exposed film is considerably wider on the Horseman than the RH8.
A little filing will take care of the soft edge, but I'm not going to try it until I test another lens and start getting some sharp pictures.
I should mention that I did consider adding a washer like you did, but when I discovered the locking bars would slide up with a little more finger pressure I stuck to original. I think the Horseman has a little more lip than the Graflex backs. I'm surprised you can't get yours to fit.
You know, reflecting back a moment here, I did try an older Horseman back and it didn't fit on my Century. That led me to try a new back which did fit, albeit tightly, which is the one that I bought. The old Horseman I tried was a knob wind.
I for one can't believe how frustrating this beautiful little camera has been.
Later, DL