Yes, just your standard Home Depot threaded rod... gives pretty accurate focus control... I wanted to add a crank rod to speed up bellows extension/collapse, but that will happen with the final version. Because there is no clutch the process can be long...Originally Posted by Tim Meisburger
Its actually very easy to get the back correct. Put it all together before cutting the glass rebate. Stick in a filmholder with a piece of scrap film inside. Turn it over and put a straightedge across the back. Take a combination square, set it on the straightedge and extend the ruler until it just touches the film. Check it all around to ensure your holder is seated parallel to the back. If it is, the distance on the ruler is the distance to the ground face of the glass. Remove the holder and use the straightedge and combination square to mark the inside faces of the ground glass frame, and this is the depth you need to cut from the outside to ensure the ground face of your glass is aligned with the film plane.
an early shot of the focusing mechanism without the rear standard being attached. This shows the threaded rod (and the initial front yoke round knobs I later replaced!)
As I recall (and it has been a couple of years) I did something similar...
Some builders have been buying rods similar to those used on the Chamonix cheaply from ebay. There was a thread about it, but I don't recall the name. For mine I am trying to use rack and pinion gears, but they are hard to find cheap, and if I had had a Chamonix to copy that seems like an easier and more economical design solution.
The secret to perfection is the clutch. Without it you turn the rod forever before you are in the field of focus for your lens. Of course, you can do a rough pre-focus if you are familiar with your subject to save turns on the rod, but a clutch mechanism (like alligator clips you squeeze to open, but when closed ride the rod's threads) would be best. I may experiment with that...
How about two delrin blocks screwed to a spring clamp that is mounted to your sliding frame with a screw through the spring hole?
Sounds correct... I'll have to get to work on it. The spring clamp is probably going to have to be either an electrical or an automotive part, I guess, for starters.
How about something like this? http://www.homedepot.com/p/HDX-3-4-i...-100656782-_-N
Not 8x10 but it could have been with a ~120mm Super Angulon.
Rafa knows this camera. 4x5, 47mm F/5.6 S/A, focusing helix, optical finder & ground glass back.
Will be up for sale in March - then the 8x10 version. This ain't no Hobo.
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