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lyonheart
2-Jan-2008, 15:38
I'm still agonising over getting a LF camera and lens. On the lenses I have some questions -

If I buy a new lens do I fit it to the lens board or will it come fitted if I order a board with it?
Does it come with a tool (some sort of lens spanner/wrench) to fit to the lens board?
Are the tools universal for all lenses or do they vary by manufacturer or lens size?
I am reasonably handy with simple technical work - would this be within my abilities or is it a specialist job?

TIA
Colin

Peter K
2-Jan-2008, 15:55
When you order a lens together with a new camera, the lens is mounted on the lens board. Also when you buy a new lens for your camera at the camera factory. Today lenses are mounted in Copal shutters. There are three different sizes, so the lensboard must have the proper hole. Tools are aviable but not from lensmakers. For the smaller shutters it's the same clockmakers use for opening wrist-watches.

Peter K

lenser
2-Jan-2008, 16:16
Communicate with the seller. Sometimes they will fit a lens to a board if they are purchased together. It's a very simple process if they don't.

Each shutter is it's own set size, so the hole in the board needs to be for that size shutter and retaining ring. If you order separately, let them know what shutter size the board needs to be for.

Lens wrenches or spanners are available, but I've never seen a situation where they are included. You may get lucky.

There are several types, from the inexpensive universal ones with four sides, each for a different retainer ring size, to the very expensive professional heavy duty spanners with interchangeable tips. You won't want to torque the lens and ring down so tightly that it takes an act of congress to remove it, so the lighter weight wrenches do a fine job.

If you can do some basic machining work, you can order the boards uncut and create the hole yourself, but it's tons easier to buy it already set for the lens.

There are a very few cameras that actually call for the lens hole to be offset to work with the camera movements and to help avoid getting the camera bed in your frame with super wide lenses. Be sure you know what your camera needs. Again, tons of communication with the seller.

You can often buy used boards in the right sizes from ebay at very reasonable prices. If the hole is too small, it's fine to have it enlarged by a good machinist, but it's easiest and least costly to buy it in the right size to begin with.

I'm lucky, one of my best friends is a machinist who has worked on both wooden and metal boards for me so that I can go from one camera system to another with perfect matches. He has even been able to machine some boards so that they work on more than one system.

You also might want to consider how to orient the lens. I have traditionally had mine on the boards with the shutter speed and f-stop scales at the top and bottom. Fine until I raise the tripod too high, then I have to use dental mirrors and sometimes flashlights to see the scales.

I recently encountered someone with what may be a better idea. He had all his lenses mounted so the scales were at 90 degrees so he could read them from the side. Much easier on a field camera, not so much so on a monorail where the standards slightly get in the line of sight to view the scales. Still, I think I will adopt his technique since most of my work requires a rather high tripod.

One other thing, if you are buying a wide angle lens, you may need a recessed board. Be sure to discuss that with your seller.

Good luck. and welcome to the world of real photography!

Tim

Scott Knowles
3-Jan-2008, 06:30
Lots of good advice and I can only add one thing. Remember that some field cameras are too small (lensboard and bellows) for some lenses with large rear lens group. I have a Horseman HD and it can take any of the older series Schneider Symmar lenses (150-210mm) but not some of the latest APO-Symmar lenses. The same applies to shorter focal length lenses, eg. under 100mm and longer focal length lenses, eg. over 240mm. They'll fit the lens board but not the camera. Good luck.

Ron Marshall
3-Jan-2008, 07:12
The front page of LF Photo has much info on lensboards etc.:

http://www.largeformatphotography.info/lenses-primer/