Linhof Technika IV and Cam Confusion / Focus Issues

[bulrich]

I have a great older Linhof Technika IV serial #62749. I got it off of Ebay some time ago and have been using it considerably for some time with portraits, interiors etc...
It came with a matching 150mm Linhof branded lens which matches the cam (both #4828883).
When I first got it I installed a Beattie Intenscreen behind the clear cheap GG. I always focus with a loupe on the GG and have been having focus problems where the focus always appears in front of the subject. Sometimes when wider open up to 6" or so. I initially thought the focus issue was due to the Beattie but it seems it may be due to the cam?

I also use a Schneider Super-Symmar XL 110 lens with the camera and it seems to have more of the focus issue. Is this a result of not having a matching cam? Did Linhof ever make a cam for a 110 lens?

Finally curious if others had problems with flash sync and the Linhof/Schneider 150?

[David A. Goldfarb]

The cam is only relevant, if you focus with the rangefinder. If you focus with the groundglass, then the cam doesn't matter.

If you focus with the rangefinder, the cam on a Tech IV should match both the lens (serial number on top of the cam) and the body (serial number on the bottom of the cam), and the infinity stops need to be set accurately.

Is the Beattie a combination groundglass and fresnel, or just a fresnel? If it is a combination, and you are using it together with the original GG, then you are using two groundglasses, and this is bound to cause problems. What do you mean by a "clear cheap GG"? The original groundglass should be matte on the side facing the lens, not clear. If the matte side is facing the wrong way, then that's your problem.

You should have a groundglass with the matte side facing the lens, and if you have a fresnel, then the groundglass should be between the fresnel and the lens, and the ridged side of the fresnel should face the glass.

If the lens is in a Synchro-Compur shutter, then it should have a PC contact for flash. If you have a lever for M or X, select X for strobes, and it should work, as long as the contacts are clean.

[bulrich]

David,
Thanks much for the quick response. The GG that came with the camera was simply a clear glass. I used it in front of the fresnel (Clear Glass>Beattie>lens).

The shutter does have a lever and was put to X. It tripped the strobes fine but negs came back blank/thin.

[Bill_1856]

On my Technika IV, the GG is behind the Fresnel screen (like a Crown Graphic).
If you focus with the rangefinder, then move the front lens standard until the GG image is in focus, there's where you set your infinity stops, and the cam should be right for the combinaton.

[David A. Goldfarb]

The clear glass might be a protective cover designed to go over the fresnel, since it is obviously not a groundglass.

If your back is like Bill's, designed to have the fresnel between the groundglass and the lens (on the later Technikas it's the other way around), and if the Beattie is a combined fresnel/groundglass, then the screen probably needs to be shimmed so that the groundglass surface is in the right place.

[Bob Salomon]

Linhof service 252 652 4401. They can straighten it out for you and reset the shims if necessary.

[bulrich]

I have it installed as per Beattie's instructions:

http://www.display-optics.com/pdf/IN...EW_CAMERAS.pdf

[Frank Petronio]

It sounds like the ground glass and fresnel need to be shimmed to match the film plane -- I wouldn't always trust third-party vendor instructions, there were a lot of different ground glass/fresnel set ups on Technikas over the years. Short of sending it off to Marflex (which is very good btw) you can do film tests where you focus on something like a line of type on a flat newspaper lying on a table top, shot low and across the sweep of newsprint from a 30-degree position. And then compare what line of type is actually in focus compared to what you originally focused on.... wide open lens of course.

Then it is just trial and error shimming and shooting film until you start getting what you are focusing on.

Then with your cammed lens, if you want to use the rangefinder, you adjust the infinity stops on the rail to make the rangefinder infinity match the ground glass infinity.

It's tedious... I rather send it off to Marflex and have it done 100% right the first time.

[David A. Goldfarb]

Marflex can also clean and calibrate the rangefinder, which is separate from setting the infinity stops, and he might make other adjustments, and replace broken or worn parts. It's an old camera. It will benefit from a proper CLA.

[E. von Hoegh]

One thing about the rangefinders - Properly calibrated, they are dead accourate. With my cammed lenses, I ues the GG only when I am using movements.

If you are focussing on the GG and your film is unsharp, the GG is in the wrong position. First verify that the GG and film occupy the same plane, then go after the rangefinder/cam. Verify the GG position first, or you'll be going in circles of ever-increasing confusion. (sorry).