Friction focussing

[Shen45]

I'm in the process of building a wooden 5x4 but getting a rack and pinion focussing setup is a bit tough here in Australia.

Has anyone made their own wooden camera and used a simple push/pull friction method to focus their camera?

How easy do you find it to use and do you find it accurate?

Does anyone have any old focussing mechanisms they would sell me?

Steve

[Ash]

Apparently Micro-Tools sell gears, racks and pinions.

I was considering building a compact 4x5, and the more I thought about ways to focus, the more I realised they got it right back in the old days. I ended up with a Korona to restore :D

[BrianShaw]

I haven't ever made my own camera, but I've used a friction focus camera - a Cambo 4x5 (errr... that's 5x4 to you guys ;) ). I have never had a problem of any real significance. On this camera the friction focus is smooth and has remained tight (the camera dates from the 1980s). The very small adjustments sometime require a tiny amount of "back and forth" dithering of the focus knob, but I'd imagine the same to be true with a rack-and-pinion unless set up with both macro- and micro-focus gearing.

[Paul Fitzgerald]

Steve,

Amund has a thread about his Shen-Ho 5x7 and posted lots of pics. It has threaded inserts to set the front standard for focal length and the rear uses a screw thread for focus adjustment. You could use friction focus for the front and 4 - 6 inches of threaded focus adjustment in the rear for fine focus. Threaded rod, nuts and washer should be available everywhere, even down under.

Amund's Shen-Ho 5x7 (http://www.largeformatphotography.info/forum/showthread.php?t=19657)

Just a thought.

[Greg Lockrey]

I have a build it yourself kit camera made by Bender. It's all friction. Works reasonably well for a $90.00 camera made all of wood. Was a neat project to do during the long Michigan winter months too.

[David A. Goldfarb]

You can probably find gear track and related parts at www.mcmaster.com

[Colin Graham]

Lead screws like on Amund's shen-hao are pretty pricey, possibly more so than rack and pinions. Regular all-thread and nuts would probably have too much slop or backlash for a focusing mechanism. If you have a local bearing supplier they can likely order directly from Boston gear or SDP/SI

[Jim Jones]

Steve,

Amund has a thread about his Shen-Ho 5x7 and posted lots of pics. It has threaded inserts to set the front standard for focal length and the rear uses a screw thread for focus adjustment. You could use friction focus for the front and 4 - 6 inches of threaded focus adjustment in the rear for fine focus. Threaded rod, nuts and washer should be available everywhere, even down under.

Amund's Shen-Ho 5x7 (http://www.largeformatphotography.info/forum/showthread.php?t=19657)

Just a thought.

Several view cameras, such as New Vue and Baco have used this system. As I recall, it worked well enough on my New Vue decades ago. Hardware store threaded rod and bushings should work, especially if the play is taken out of the threads. I've seen, but not used, a studio camera that used a V-belt focusing system. A spring loaded flexible wire looped several times around the focusing shaft and attached at both ends to the camera bed might work.

[Michael Wynd]

Hi Steve,
I still have most of my old Nagaoka 4x5 with the focussing rack. If you want it, it's yours. All I'll need is an address to send it to. Send me an email on mwynd@gordontafe.edu.au
Mike

[Shen45]

Email sent Michael

Steve