Help Needed: Technikardan 45s - Fresnel behind Maxwell Glass

[Ben Chase]

The TK45s that I bought last December, I just now discovered has a fresnel installed in front of the GG (between the GG and the lens). Not sure why the previous owner had installed it this way, but perhaps just a simple mistake.

I've been having a few focus issues recently and I had read on here that this can be a possible cause. It's hard for me to tell whether or not the 4 microscrews have been adjusted (which would move the shim).

This picture below shows the fresnel underneath the GG, the red circles show part of the GG frame that's bent downward against the GG - Is this normal? It appears on all four corners of the GG frame.

Is there a safe way for me to take out that fresnel and return the shims to factory position if they were adjusted? I want to make absolute certain this groundglass is in the correct position.

Forgive the paranoia, but if there is anything wrong, I'll need to get it fixed before June 23, as that's when I'm leaving to Glacier - any suggestions?

[Michael Kadillak]

I would get on the phone to Marflex first thing in the morning to see if you can get an express service order for a ground glass alignment ASAP. You can dance around the issue attempting to solicit alternative solutions but at the end of the day you need to know with absolute precision that every millimeter of your ground glass is spot on - period. Considering the fact that you have an important trip scheduled and have a forward investment in film and chemistry to have these negatives developed it is a nominal amount of money prudently invested in peace of mind. Anything short of the real deal is suspect IMHO.

Look at the bright side. You own a marvelous camera in a Linhof and it will service you for many years to come.

Cheers!

[John Powers]

I hope you will tell us how you proceed and how it works out. Besides concern for your situation I have a TK45 with a Bosscreen and would like to learn more about the ground glass alignment.

Your trip sounds great. Hope that will be a future thread.

John

[RPNugent]

Bob Salomon will probably respond at some point, but it sounds to me like you have the unlined Superscreen in front with a ruled glass behind it. If so I think this works fine from someone else I know who used it that way.

[Brian Ellis]

I don't understand the set-up at all. You say you have a "Fresnel behind Maxwell Glass." Maxwell is itself a Fresnel. So you have two Fresnels next to each other?

I've owned three Linhof cameras, a Technikardan and two Technikas, I've had everything on them from a plain ground glass (Technikardan) to Beattie (the Master Technika came with it), BosScreen (on the Technika V), and Maxwell (replaced the Beattie). The one thing I've learned is that replacing screens on a Linhof is something that has to be done with great care, more so than many other cameras I think. My Maxwell came with very detailed instructions for installing it and also included substitute shims and maybe screws to use in place of the ones already on the camera. And I still messed it up - the first time I used the camera after installing the Maxwell screen all 50 sheets taken on a 3 day trip were totally fogged.

My point is that you have what seems to me an odd set-up if you really have a Fresnel and a Maxwell screen next to each other, certainly one that has a high potential for screw-ups when it was installed by whoever installed it. I'd call Bill Maxwell and see what he suggests, I wouldn't call Marflex, at least not first. Martin knows Linhof screens and the Linhof shims, screws, etc., he may or may not know about the substitute stuff that Maxwell provides for his screens when they're installed on Linhof cameras.

[Ron Bose]

AFAIK and remember, my TK45s has a fresnel with ridges on the lens-side and a rough surface on the viewer side. Then between it and me the viewer is a glass screen with a grid marked on it.

The fresnel I describe may be a Linhof 'superscreen', but I'm not sure.

The proof of the pudding is the eating. Get a Polaroid back or a regular film back. Shoot a tape measure perpendicular to the film plane, focus on a particular increment, use a wide aperture for minimal DOF and see what you get.

Chances are, if you bought the camera used, the last owner had it set right.

Cheers !

[Bob Salomon]

The TK is shipped from the factory with a Linhof grid ground glass. The ground glass is held in place by a retaing clip on either end. That retaining clip is mounted to the back with three screws. On the middle screw there is a swinging chrome metal clip that holds the fresnel in place.

The Linhof ground glass has the Linhof logo printed on it and has slightly clipped corners. The Linhof fresnel does not have clipped corners.

The picture you posted shows a non Linhof GG and the middle hold-down screw as well as the clip for the fresnel are missing from the hold-down clip.

Why don't you ask the owner:

1: What screen he installed
2: Did he install it or did a service center install it?
3: Were the GG shims adjusted properly for the fresnel inside the GG?
4: Where are the missing screws and clips?

In any case it would be best to have Marflex check that everything is in factory spec. since it is obvious that the back is not.

Marflex is marflex@aol.com

[Ben Chase]

I don't understand the set-up at all. You say you have a "Fresnel behind Maxwell Glass." Maxwell is itself a Fresnel. So you have two Fresnels next to each other?

I've owned three Linhof cameras, a Technikardan and two Technikas, I've had everything on them from a plain ground glass (Technikardan) to Beattie (the Master Technika came with it), BosScreen (on the Technika V), and Maxwell (replaced the Beattie). The one thing I've learned is that replacing screens on a Linhof is something that has to be done with great care, more so than many other cameras I think. My Maxwell came with very detailed instructions for installing it and also included substitute shims and maybe screws to use in place of the ones already on the camera. And I still messed it up - the first time I used the camera after installing the Maxwell screen all 50 sheets taken on a 3 day trip were totally fogged.

My point is that you have what seems to me an odd set-up if you really have a Fresnel and a Maxwell screen next to each other, certainly one that has a high potential for screw-ups when it was installed by whoever installed it. I'd call Bill Maxwell and see what he suggests, I wouldn't call Marflex, at least not first. Martin knows Linhof screens and the Linhof shims, screws, etc., he may or may not know about the substitute stuff that Maxwell provides for his screens when they're installed on Linhof cameras.

What I meant to say was that the maxwell was installed underneath the groundglass, toward the lens side. Just about everything I've read here indicates that a fresnel needs to be installed facing the user's eye, otherwise there will be a focus shift.

I've already sent it priority overnight to Marflex to ensure that the groundglass is seated properly and the shims are in the correct position.

[Ben Chase]

The TK is shipped from the factory with a Linhof grid ground glass. The ground glass is held in place by a retaing clip on either end. That retaining clip is mounted to the back with three screws. On the middle screw there is a swinging chrome metal clip that holds the fresnel in place.

The Linhof ground glass has the Linhof logo printed on it and has slightly clipped corners. The Linhof fresnel does not have clipped corners.

The picture you posted shows a non Linhof GG and the middle hold-down screw as well as the clip for the fresnel are missing from the hold-down clip.

Why don't you ask the owner:

1: What screen he installed
2: Did he install it or did a service center install it?
3: Were the GG shims adjusted properly for the fresnel inside the GG?
4: Where are the missing screws and clips?

In any case it would be best to have Marflex check that everything is in factory spec. since it is obvious that the back is not.

Marflex is marflex@aol.com

Thanks Bob - I called Martin this morning and spoke to him. My GG frame is on it's way there right now to ensure everything is within spec. It's the only way to be certain - I don't want to be worrying about this when I'm shooting $400 worth of film.

Thanks,

Ben

[Michael Kadillak]

You made the best decision possible Ben as your situation is rather unique and there is really no way of being able to put your arms confidently around a reference point of ground glass registration buying in the used market. I have spoken to Martin Arndt many times on the phone with a myriad of Linhof questions over the last few years and he is as good as they get relative to knowledgable customer service. The staff at Marflex cammed several lenses for me for my Master Technika a few years ago and I was simply amazed at the precision of their work.

Have a great trip. I am heading to Montana at the end of the month to visit family and do some shooting as well.

Cheers!