View Full Version : lens mystery...

14-Feb-2006, 07:00

I am having trouble with a lens/4x5 combo. Actually, it's a Cambo (no pun intended). I am unable to focus a 127mm Kodak Ektar on this camera. I have called Calumet; I was informed that I should perhaps "rethink" large format photography since I am unable to do this. Another person, from a retailer in NY, told me it HAS to focus, given that a 90mm will focus on a Cambo.
I have tried everything, including moving the rail clamp in front of the standard clamps.

The lens works fine on my Speed Graphic. I am particularly fond of this piece of glass, and would like to use it on my monorail. Any suggestions...(I guess a recessed board is in my future).

14-Feb-2006, 07:06
Is it on the same board? Or did you remount it? I'm guessing you remounted it. Maybe it's not screwed tight. Maybe there is a different issue with the new or old board.

Ted Harris
14-Feb-2006, 07:08
Percy, you need to give us some more info. The problem may be that you do not have a long enoough rail to acheive the need extension. This couldbe the case ifi you are trying to focus on an object that is placed close to the lens. Remember that the bellows extension needed for a lens increases as the object you want to bring in focus gets closer to the lens/film plane. At one-to-one for example, you need twice the bellows extension you need at infinity. Having said that, 250+ of rail is still rather short. You mentioned a recessed board and this leads me to believe you are going in the wrong direction to acheive focus ... you may need more extension, not less. If you are trying to focus at infinity then the above doesn't apply ... all a guess without more detail on exactly what you are doing that isn't working.

Ben Calwell
14-Feb-2006, 07:41
If you're using a loupe to focus on the ground glass, check to make sure the loupe is adjusted to your eyesight. It happened to me once. A few years ago, I thought I couldn't focus a lens on my newly acquired Linhof, but it turned out that my adjustable loupe had become "unadjusted" to my eyesight. It was embarassing, because I sent Jim at Midwest (where I bought the camera) a frantic e-mail claiming I couldn't focus the camera. But it just turned out that my loupe was out of adjustment for me. After I focused the loupe to my eyesight, everything popped into focus on the ground glass.

14-Feb-2006, 09:06
I know how to focus...it is not an issue of inadequate bellows extension. The lens is mounted on the graphic (4x4) board, which is in turn mounted on a Cambo 4x4 adapter board. There is no issue with my loupe; I have 20-10 vision...better than average.

neil poulsen
14-Feb-2006, 09:30
"I was informed that I should perhaps "rethink" large format photography since I am unable to do this. "

This is terrible. Obviously, that Calumet person hasn't had a lot to do with large format. Probably never shot a roll of film.

Have you used this lens before?

Ron Marshall
14-Feb-2006, 09:36
Percy, is the problem that you cannot get the lens close enough to the ground glass to form an image?

Conrad Hoffman
14-Feb-2006, 09:57
No rocket science here- hold lens and board in left hand with shutter open. Focus a distant object on a piece of paper held in right hand. Note distance between lens and paper. It should be about 127mm! Figure out why you can't achieve that distance in the Cambo- maybe the adapter is too thick. Get recessed board if necessary. Does one camera have a fresnel screen, and the other not? They'll be brighter, but harder to focus with. A few minutes doing some rough checks with a ruler should sort this out.

Sam Crater
14-Feb-2006, 10:27
Conrad has the right idea. Focus the lens on a piece of paper. If you can't focus on the paper, the lens is mis-assembled. If you can, measure the distance to the paper and figure out why you cant achieve the same focus at the same distance with your camera.

William Mortensen
14-Feb-2006, 10:28
Very confusing situation, given that the lens focuses fine on your press camera. The camera really doesn't do anything but hold the lens on one end and the ground glass on the other, and keep out the light inbetween. One possible guess- could there be a fresnel screen installed on the wrong side of the ground glass? What kind of image do you get with the bellows set to about 127mm?

Jack Flesher
14-Feb-2006, 10:32
Sounds like the lens cell spacing changed when you mounted it on the Cambo...

14-Feb-2006, 11:51
Ron, that is exactly the problem!

Sam Crater
14-Feb-2006, 12:04
Percy, that sounds odd. Either the camera or the lens has got to be mis-assembled. If we knew how far from the lens the image is actually forming, or how far apart your lens board and ground glass are, we could maybe guess which.

Juergen Sattler
14-Feb-2006, 12:32
Is it possible that the bellows is so old that it won't fold closely enough to allow for the 127 to focus - does it compress completely? I've seen bellows that just couldn't compress enough to focus a short lens (not that a 127 for 4x5 is that short!) Do you have any other lenses you could try on that camera? This is a weird problem.

Alan Davenport
14-Feb-2006, 13:00
Which model of camera are you using? If this is a new-to-you camera, perhaps someone turned the standards the wrong way. On later model Calumets (the ones which use 6 inch+ square lensboards) the standards can be turned around, since the bellows, lensboards and back all attach exactly the same way. The standards can be set to allow minimum bellows, or turned the other way to get the most extension out of a short rail. If both standards are turned so they are away from the bellows, it looks they might be too far apart to focus a short lens.

Jim Galli
14-Feb-2006, 15:18
Is the lens sitting behind the uprights at the front? If not, take bellows loose, lensboard out, and rotate the standard 180 degrees so it's an inny instead of an outy. Did you forget to put the rear group back in after you mounted it on the Cambo board? Probably not as the Ektar rear group doesn't really need to come out to switch it.

David Karp
14-Feb-2006, 15:28
Is this a Cambo SC or Calumet 45N, 45NX, or 45NX-II?

If so, then to focus the 127mm you probably need to place the tripod mounting block either in front of or behind both standards. This lets the standards get as close together as is possible. If I remember correctly, the block prevents the standards from getting close enough together to render a sharp image. This is certainly true of a 90mm, even with a recessed board.

David Karp
14-Feb-2006, 15:30
By the way, I found that a bag bellows was preferable to the standard bellows when working with my Fuji 125mm on my older Cambo, even though it was not necessary to focus the camera. It was just that the bellows was too tightly compressed for much movement. This may not be a problem if the 127 Ektar does not have a lot of room for movement.

Ron Marshall
14-Feb-2006, 16:48
Percy, with the adaptor board you may need a bag bellows. On my Sinar F1 I can't focus my 110mm (on an adaptor board) using the standard bellows. Your lens is longer, but your bellows or adaptor board may be thicker than mine. Keep watch on ebay, I've seen a few bag bellows going cheaply.

15-Feb-2006, 09:29
Thank you all for your responses thusfar. I don't know what model of Cambo the camera is ; it is not labelled. ( I have looked).
Jim, yes, it has 6 inch plus square lensboards.
Jim and Alan, thank you, I will try to implement your suggestions this evening.

David Karp
15-Feb-2006, 12:14

Is it the model with an approximately 1 inch square monorail with a small tripod mounting block that grabs around the rail? (If you are not sure, take a look at the monorail camera shown with the Cambo to Linhof Technika type lensboard adapter in this article http://www.largeformatphotography.info/lenses-primer/)

If it is this camera, the tripod mounting block interferes with the travel of the standards on the rail. Try placing the mounting block in front of the focusing wheel on the front standard. I think you will find that this will let the standards get close enough together to focus properly.

15-Feb-2006, 12:51
No it won't. As I indicated in the original post. I tried this. It was to no avail.

15-Feb-2006, 13:06
Percy, if your Cambo has a monorail which looks like an aluminum block approx. 1x1 inch in cross section without special grooves in it like Dave described in his question, then it could be either one of the 45N/NX/SC models or it could be even a Calumet 540.

If this is the case, you can try two things:

1. Move the tripod mounting block either ahead of the front standard or behind the rear standard so that it does not sit between the two standards

2. In addition, you can reverse-mount one or even both standards, so that they face each other.

You could gain up to about two inches combining these two procedures. This techinique works even with 90 mm lenses, so it should work with 127 mm one.


David Karp
15-Feb-2006, 13:13
Sorry Percy,

I read too fast and missed that part of your post.

Have you tried what Marko suggests, reversing the standards? If not, that might work. The lensboard itself should be behind the front standard, and the groundglass should be behind the rear standard. If you have a camera like the one in the photo in the above article (mine) you should be able to rotate the standards 360 degrees without removing the standard from the rail.

18-Feb-2006, 14:17
Reversing the lensboards worked.
Thank you all for you repsonses. Still don't know the model of the camera though...

18-Feb-2006, 16:19
Now call Calumet and tell the guy you talked to that he should rethink giving advice on large format.

David Karp
18-Feb-2006, 18:32
Now after all this it occurs to me that I should have told you this long ago, just did not come to mind. If you need to ask a LF question to someone at Calumet, call Jose in the repair department in the main office in Chicago. He knows what he is talking about whether you are asking questions on Cambo/Calumet cameras or Caltar lenses. Glad things are now working.

David Karp
19-Feb-2006, 12:31

And here is another thing you can do now that you know the standards can rotate: I used to use my Cambo with the 1" square rail with an 11.5" rail quite often. This was perfect for wide angles, and also for any lens up to 210mm. And now for the cool trick! If you rotate the front standard so that the board is in front of the standards you should be able to focus a 300mm at infinity and a bit closer too.