Linhof Super Tech IV 6x9 Help

[wjlapier]

I took on the restoration of a well used (abused?) Linhof Super Tech IV 6x9 camera. No leather and painted black. It was mess and took quite a while to remove the paint and clean the areas where the leather would go if I were to have some installed. Mechanically, the camera works very well. Nothing binding or frozen. No lens or rear ground glass but it did come with a circular lens cam for 65mm, 105mm, and 180mm. There are stops for 65mm and 105mm. Not the 180mm--why?

My initial plan was to create a camera that would shoot only 65mm. I'm sure folks will say it can't be done without the original lens, or that the camera needs to be sent in for a CLA, and so on. With that undersood I'm hoping I can work through a couple or issues. The first being using a lens not matched to the lens cam. Next, finding infinity focus and working from there. My first try at using this camera, and never shooting a Linhof, I came out with blurry images using the infinity stops on the top rail. Next, after finally finding the correct manual I realized I needed to slide the top rail back one click and then place the front standard in the 65mm stops. Now, the in focus plane ( infinity ) was near to me and the object out into infinity was slightly blurry. Shooting at f/16. Without a ground glass which way should the standard move--further back towards the film plane or a little further way? There are scratch marks on the top rail in front of the 65mm infinity stops.

If I had a ground glass, any way to "match" the lens to the lens cam without modifying the cam? This thing is so beat up I've considered removing the rangefinder and shoot only with a ground glass.

I don't want to sink a bunch of money into this camera. Anyone with a "can do" attitude and willing to help I'd appreciate it.

 

[Dan Daniel]

Get a ground glass. The only way to really check infinity focus and the matching of the cam to the lens.

Well, actually, what you need is a piece of ground glass to go in the film plane of the film holder. And then you need to confirm that your new focusing ground glass matches the same plane as the film holder focus plane.

After you get ground glass working, adjust for ininity. Then check focus at other distances- I use 4 feet and ten feet generally. If closer focus points are off, adjust for close focus and let depth of field handle infinity? Depending on how you shoot.

After this, you can then experiment with either reshaping cam or using it as the jumping off point for making a new one. I don't know that camera but I assume that there is some sort of cam follower. You can play with this- if moving cam follower away from cam kaes focus go out, then you need to shave down cam. If it makes it get closer, you need to add material to cam.

If you are going for a single lans camera, I would make a new cam, use existing one as rough template, and shape a new one using trial method. 3 or 4 or 5 points get established, then shape a smoth curve between points. AFter you play with cam and rangefinder for a bit oyu'll get a feel for the subtlety (or lack) of the rangefinder and will be able to determine how precise any curve and shaping needs to be.

 

[abruzzi]

So I've been fixing up a 6x9 Tech III and have encountered similar questions. One thing I have noticed--I have two 180s--both tele-Artons, one ƒ5.5 and one ƒ4. I have found the 5.5 is more-or-less at infinity at the third detent (the III doesn't have flip up stops like the 4x5 technika, but instead has detents drilled on the rail, not sure about the IV.) But the ƒ4 focuses at infinity at the same detent as the 105.

I don't know yet how likely it is to match a similar lens for the rangefinder. I do know that my tele-arton 180mm ƒ4 absolutely doesn't match at all. the ƒ5.5 seems closer, but I haven't had a chance to properly test it. Given the greater depth of field, I suspect the 65mm will have an easier time matching. In the ned, if the lens matches the cam, great, but I don't know that there are many options to adjust. If the infinity stops are like mine, they're not adjustable, if they're like the 4x5 technika, they are adjustable. But other than adjusting the infinity point, the only other adjustment I can see involves a file on the cam.

 

[wjlapier]

The infinity stops on the IV are drilled holes color coded to the cam. I believe black for 65mm and red for 105mm. No holes for the 180mm even though there are serial numbers on the cam for such a lens.

Just played with a ground glass I have for a 4x5 camera. It's recessed about where the film plane is for the film back. It seems the lens needs to go back towards the film plane a little to obtain infinity so I'm wondering if I found a recessed lens board for the lens if I could use the 65mm stop and just focus with a ground glass. BTW, the Linhof ground glass backs are more than I would like to spend and I thought of using another Linhof film back I have to make a ground glass back. But finding a GG that would fit the film back is also costly just to play around with.

 

[abruzzi]

My point was that your camera probably came with the tele-Arton 180mm ƒ4 because it has nearly the same infinity position as the 105mm (I actually can't find specs on my 105mm, but being a non-tele, I assume it is close to 105mm.) According to http://www.hyam.net/blog/archives/3961 that particularly 180 has a FFD of 102.4mm. The 5.5 has a FFD of 115.5. over a centimeter difference.

 

[wjlapier]

Good to know. Thanks!