PDA

View Full Version : Tachihara 4x5 5x7 step up back



Ginette
28-Jan-2010, 17:15
RE: this topic http://www.largeformatphotography.info/forum/showthread.php?t=58446

For the benefit of all users who might be interested to the Tachihara 4x5 5x7 step up back and wish to know if it can fit others brands.

Mr Salomon proposed to measure an original back.

Here mine, a Zone VI model (middle production). Can you post the exact mesures corresponding to the letters. And maybe some pictures of the back.

Bob Salomon - HP Marketing
29-Jan-2010, 14:34
THE AREA THAT MOUNTS TO THE CAMERA BACK IS 6 5/8" square. The overall size is 8.5" square. So the part that mounts to the camera is 3/16" too large in both directions.

Ginette
29-Jan-2010, 16:12
THE AREA THAT MOUNTS TO THE CAMERA BACK IS 6 5/8" square. The overall size is 8.5" square. So the part that mounts to the camera is 3/16" too large in both directions.

Thanks for theses measurements.

If the 6 5/8" is the C and D, it can be very easy to remove 3/32" on each side with a router. What is the depth of the "seal step" ("E" in my picture)?
If the 8 1/2" is the A and B, this will need to remove a whole 3/8" on each side, this depend on how the back is constructed. Can you post a photo of the back as I suspect that the one post in the original thread is not a Tachihara but a Nagaoka or Ikeda as Bryan post about.

The expansion back that I have on my Nagaoka 4x5 (same as a Calumet wood field, I think) looks identical to the one that John listed in the original post. I think that it might also fit the Ikeda 4x5. The outer mounting flange is apx. 6 13/16" (173-ish mm) square and the inner "seal step" is 6 3/16 (158mm). There are no pins and the mounting flange thickness is apx. 1/4". Curious to see if it is the same measurements as those that Bob markets through HP - may fit several different brands.
Can you measure also the deep of the mounting flange ("F" in my picture)
Thanks for the info.

Ginette
31-Jan-2010, 13:11
Hello again Mr Salomon,

Can you indicated me also the deep of the unit, ex. from the ground glass to the camera mount (perpendicular, not the side lengh). I think problems with some lens occur because unit is too compact to be in the right prolongation of the bellows angles. RE: problems as described by QT Luong here (http://www.largeformatphotography.info/tachihara.html)
Hope it's clear, sorry for my bad English.

Bob Salomon - HP Marketing
31-Jan-2010, 13:24
Hello again Mr Salomon,

Can you indicated me also the deep of the unit, ex. from the ground glass to the camera mount (perpendicular, not the side lengh). I think problems with some lens occur because unit is too compact to be in the right prolongation of the bellows angles. RE: problems as described by QT Luong here (http://www.largeformatphotography.info/tachihara.html)
Hope it's clear, sorry for my bad English.

About 5 or 6" deep but I can't measure it as I am traveling until the 25th of next month.

Ginette
31-Jan-2010, 14:32
About 5 or 6" deep but I can't measure it as I am traveling until the 25th of next month.

5-6" should be enough to not have long lens problem. "Your unit" is probably definitevely deeper that the one posted in the original Sales topic (http://www.largeformatphotography.info/forum/showthread.php?t=58446).
Maybe the QT Luong test was not made from an orignal Tachihara back or the back was corrected since.

Can you confirm also the size you gave earlier are the A-B-C-D ones ? Thanks