Linhof Technikardan 45S Ground Glass Reinstallation

[naturephoto1]

Hi all ,

This is my first post on APUG, and though I have had my Linhof Technikardan 45S for over 10 years, this was the first time that I had to remove the Ground Glass.

I removed the camera Ground Glass to confirm the dimensions of the glass to place an order for a Satin Snow Ground Glass. I use the Linhof Fresnel Lens with the camera standardly.

Here is my problem, when I removed the Ground Glass the 4 shims supporting the Ground Glass fell out. I think that I know how to put the assembly back together, but I would appreciate it if someone could confirm.

As far as I can ascertain, the shims (which have small holes) should fit back on the small pins to the inside of the 4 screw holes which are in the 4 corners of the bottom of the frame holder. Also, it appear that the holes in the shims are not exactly centered. As I have tried to reassemble the parts, it appears that the narrower (thinner) part of the shims should be situated on the inside closest to the film gate. Are these conclusions correct?

I understand how retaining plates, which hold the Ground Glass, fit back into the frame holder (with the rotating center clips positioned to "lock in" the Fresnel Lens). I think though that the plates have to be positioned so that the Fresnel Lens will fit freely in between the plates so that it drops into the well and the rotating center clips swing to lock the Fresnel Lens in place. Is this also correct?

I would appreciate any comments and confirmation of what I am doing.

Thanks very much.

Rich

 

[MichaelBriggs]

Hi all ,

.........

As far as I can ascertain, the shims (which have small holes) should fit back on the small pins to the inside of the 4 screw holes which are in the 4 corners of the bottom of the frame holder. Also, it appear that the holes in the shims are not exactly centered. As I have tried to reassemble the parts, it appears that the narrower (thinner) part of the shims should be situated on the inside closest to the film gate. Are these conclusions correct?


I understand how retaining plates, which hold the Ground Glass, fit back into the frame holder (with the rotating center clips positioned to "lock in" the Fresnel Lens). I think though that the plates have to be positioned so that the Fresnel Lens will fit freely in between the plates so that it drops into the well and the rotating center clips swing to lock the Fresnel Lens in place. Is this also correct?

.....

The metal strips that you are calling shims fit on to the small pins on the ends of the screws. The holes are to hold them in place. (They will rotate until you tighten the retaining clips that extend the width of the ground glass.) If by the narrow part you mean that the hole is not precisely centered in the width of the metal strip, then this isn't critical. Perhaps if you oriented the metal one way, it would very, very slightly obstruct the ground glass view. The only critical dimension is the thickness. (I prefer not to call these strips shims because the ground glass position and focus accuracy aren't adjusted by procuring a different set of shims with a different thickness -- the ground glass is adjusted by turning the screws that the metal strips rest upon. Of course, you have no need to do this, and should not turn these screws.)

I don't have a Fresnel lens on my TKS, but your description seems very plausible. On my camera the center clips have no function. The critical aspect is to keep the Fresnel lens on the same side of the ground glass as it was originally located. And of course the ground surface of the ground glass should face the lens.

 

[naturephoto1]

The metal strips that you are calling shims fit on to the small pins on the ends of the screws. The holes are to hold them in place. (They will rotate until you tighten the retaining clips that extend the width of the ground glass.) If by the narrow part you mean that the hole is not precisely centered in the width of the metal strip, then this isn't critical. Perhaps if you oriented the metal one way, it would very, very slightly obstruct the ground glass view. The only critical dimension is the thickness. (I prefer not to call these strips shims because the ground glass position and focus accuracy aren't adjusted by procuring a different set of shims with a different thickness -- the ground glass is adjusted by turning the screws that the metal strips rest upon. Of course, you have no need to do this, and should not turn these screws.)

I don't have a Fresnel lens on my TKS, but your description seems very plausible. On my camera the center clips have no function. The critical aspect is to keep the Fresnel lens on the same side of the ground glass as it was originally located. And of course the ground surface of the ground glass should face the lens.

Hi Michael,

Thanks for the reply.

If we are both understanding each other what I am calling shims (perhaps incorrectly) and what you are calling metal strips do in fact fit on the pins to the inner side of the screw holes. I believe then as I suspected, the metal strips just act as support to position the Ground Glass at the proper focus distance from the lens standard.

Rich

 

[MichaelBriggs]

Yes. The assembly order is to lay the metal strips / shims (each 4 x 25mm) on the pins on the ends of the screws, using the holes in the strips/shims. The place the ground glass on top of the strips/shims, with the ground side facing the lens. The combination of the screws and the strips/shims determines the position of the ground glass -- if you had a need to change the position of the ground glass, which you don't, you could turn the screws from the other side. Then place the two long retaining clips in place (each 11 x 100 mm) on top of the glass, then two screws for each retaining clip. Then I suppose the Fresnel and the clips in the center.

When you get your Sain Snow ground glass, you do the same thing. The thickness of the glass doesn't matter. Just keep the ground surface facing the lens. And never change the order of ground glass and Fresnel lens -- the pair can be configured either way, but the focus will be wrong if you change the order. It sounds like you camera has ground glass closer to the lens, Fresnel closer to the photographer, so keep this configuration.

P.S. The lesson is that when you take something apart, take notes. Or take photographs. This is a lowly task for which a d*****l camera is suitable.