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jmontague
25-Oct-2015, 13:27
I have a Burke & James 4x5 Press camera. When I extend the front standard/bellows and lock them into place, the lens board and film plane are not parallel. I understand that, while the front standard is supposed to lock in place parallel, the system is not that perfect. So, I'm slightly torquing the standard get the alignment right (constant checking of the right and left sides of the GG while focusing).

Does anyone know how to adjust the standard so that it locks in place as closely as possible to parallel to the film plane? Thanks.

Oh, the camera has been well looked after - no signs of abuse or trauma.

Dan Fromm
25-Oct-2015, 13:38
That's what the bed -- also called infinity -- stops are for. Does your camera have them? You can see them clearly in the top left photo here: http://lommen9.home.xs4all.nl/Burke/

Tin Can
25-Oct-2015, 13:40
I just looked my 2 B&J Press, they are rough,well used and straight as I need them.

What dimension is out of whack?

Pictures always are a good idea.

wombat2go
25-Oct-2015, 14:24
https://app.box.com/s/ph2jel7gupxl1tiifi4flatrv1uvrrrb

Here is one way to do it, using a gauge table with the camera back resting on parallel blocks

Dan Fromm
25-Oct-2015, 15:09
Arrgh! By Occam's razor, the problem is bed stops or lack thereof. Press cameras are set up by pulling the front standard out until it contacts the stops firmly. The stops are normally set so that, depending on the rangefinder fitted to the camera, with the front standard at the stops the lens fitted will focus exactly to or a tiny bit through infinity.

Press cameras set up for multiple lenses often have multiple sets of bed stops. Bed stops are easily set by using the rails' front ends as reference points.

Another way to set up a press camera without stops is to use what the late Fred Lustig insisted was called a chinaman. This is piece of metal perhaps an inch long with a "T" shaped cross section that fits snugly between the rails. Since the B&J's front standard has squeeze locks a chinaman for it will have to be cut away to clear them and will have to be more than an inch or so long. I use chinamen (one for each camera, their rails aren't exactly as far apart) with my 2x3 Pacemaker Graphic and 2x3 Century Graphic.

Jim Jones
25-Oct-2015, 16:43
One of the advantages of Speed Graphics over much of the competition was those fold-down infinity stops Dan mentioned. B&J infinity stops didn't fold down. If one used several different lenses, the B&J stops should be set for the longest lens and a Chinaman laid on the front rails between the stops and front standard with shorter lenses. While a B&J comes close to positioning the front standard parallel to the film plane without infinity stops, there is a little room for error. Different models of B&J use slightly different stops. They can be improvised in a variety of styles.

Tin Can
25-Oct-2015, 16:56
Now I know what to call the 2 'plates' I use on my Japanese Horseman VHR.

Must be a railroad term...

jmontague
25-Oct-2015, 17:06
Does anyone have a photo of the "chinaman"? I removed the infinity stops because I do change lenses (210, 135 & 90). I like the idea of setting the stops for the 210 and having a tool to assure alignment for the lower mm lenses.

Tin Can
25-Oct-2015, 17:20
Does anyone have a photo of the "chinaman"? I removed the infinity stops because I do change lenses (210, 135 & 90). I like the idea of setting the stops for the 210 and having a tool to assure alignment for the lower mm lenses.

Not for a B&J and they would all look different for different cameras. It's a spacer made of metal that goes between the stops and the front standard and lays captive flat on the bed between them.

Dan Fromm
25-Oct-2015, 17:22
Does anyone have a photo of the "chinaman"? I removed the infinity stops because I do change lenses (210, 135 & 90). I like the idea of setting the stops for the 210 and having a tool to assure alignment for the lower mm lenses.

Well, there's your problem. You shot yourself in the foot.

See figures 27-30 on pages 39 and 40 in http://www.galerie-photo.com/telechargement/dan-fromm-6x9-lenses-v2-2011-03-29.pdf

You'll need a somewhat different chinaman, with a center section -- well between the rails -- that will clear the standard's squeeze locks.

jmontague
25-Oct-2015, 18:22
Thanks for the ideas. As I do not have a Bridgeport milling machine laying around, making an accurate "chinaman" like that in the link Dan provided, would be difficult for me. I will have to figure out another solution. I wish the B&J had Crown Graphic style fold away stops. For now, painfully careful focusing will be the answer.

Dan Fromm
25-Oct-2015, 18:58
Where's your imagination? http://www.amazon.com/Tools-Combination-Square-Metal-Body-1794468/dp/B005XUHI98/ref=lp_3006710011_1_12?s=hi&ie=UTF8&qid=1445824418&sr=1-12

You may want to mark the rails for each lens. To make life easier for yourself, set up your pair of stops for y'r 90, if necessary position them behind the standard. Doing this requires that the 90 make infinity on the outer bed. If it doesn't the "drop the bed, run the standard off the inner rails, raise the bed, pull the standard and bellows out and put the standard on the bed rails from the front" trick won't work.

Oh, and by the way, you don't have to make a chinaman or several yourself. SKGrimes will be happy to make one or several for you. They made the one I use with my Century Graphic.

Jim Jones
26-Oct-2015, 08:03
When there are infinity stops correctly placed for the longest lens used on a B&J press, Chinamen are easy to fabricate. I'd set up a fence on a table saw and make them from sheet aluminum with a fine-tooth blade. Less intimidating material than aluminum should also work. Some models of B&J require a cutout in a Chinaman for the front slide lock, others do not. If a B&J has no infinity stops, a properly made Chinaman that precisely fits either inside or outside of the rails can insure the lens and the film are parallel. The longer that Chinaman is, the more accurate it can be. Making such a Chinaman is easy enough for a competent machinist with precision tools, or possible for a master craftsman with primitive tools. If one doesn't want to wrestle with machining a precise one-piece Chinaman, A sheet of metal or other stable material can be fitted with sliding or rotating cams that can be adjusted to a camera that is perfectly aligned. Then the cams can be pinned in place to prevent further change. As Dan suggests, use your imagination. Reduce a problem to its most basic elements and build a solution from that. Too often we complicate problems with a surplus of sophistication.

wombat2go
26-Oct-2015, 09:10
Not as accurate as the metal spacer, but perhaps easier, just requiring drilling a scale rule.
The scale can be non destructively mounted on the bed using existing screws. ( At least, on the 4x5 Speed)

Then record the infinity settings for the lens in the book.
That way, I can use , say, the old Computar variable focal length 105~150mm lens hand held with the roll film back.
Here is a photo from that lens with the RH-8 back. ( when set to 135mm, the native rangefinder on the Speed is accurate)
https://app.box.com/s/aqvznhvq37b4pwuyfupv