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View Full Version : Trust, but verify...



Steve Goldstein
1-Aug-2008, 15:45
Several years ago I purchased a new Shen-Hao HZX45-AII while traveling in China. It came with one Technika-style lensboard with an offset-low hole, i.e. the hole was not centered in the light trap circle. Since this was the original equipment I naively followed along and picked up a few other offset-low boards over the years.

Today I discovered that a recently-purchased lens came in a board with a centered (in the light trap) hole, and I had some free time. I'd never thought to check the camera's zero positions, and here was my chance to do so and compare lensboards. I set it up very carefully and positioned a target on the wall at exactly the same height above the floor as the lens' center, using an offset-low board. The image was not in the center of the ground glass, it was off by almost 1cm! I swapped the lens to the centered board, and the image was much closer to the center (I did not readjust the target for the small difference in lens height, because I didn't think of it, but it would have been the right thing to do).

This is all somewhat academic since the camera has more than enough front rise and fall for me, but it was certainly a surprise. At least I've learned (among other things) that the difference is small, and that in the future I needn't be so picky about lensboards for this camera.

Bill_1856
1-Aug-2008, 16:30
If it makes you feel any better, I did the same thing last week for the first time with my Nagaoka, which I've owned since the 1970s. Same conclusion! D'oh!

Peter K
2-Aug-2008, 09:45
This is a good example for imitate something without the knowledge of the connections. The offset-low hole makes sense with the front standard of the Linhof Technika to center the optical axis of the lens in the front standard's zero position.

Another example is the famous hole in a part for the Leica III (?). This hole was drawn befor a modification was made and the drawings for production where not changed. But this hole was in early russian and japanese Leica copies too.