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View Full Version : Help Needed: Technikardan 45s - Fresnel behind Maxwell Glass



Ben Chase
10-Jun-2007, 18:14
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
10-Jun-2007, 20:12
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
11-Jun-2007, 03:35
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
11-Jun-2007, 05:07
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
11-Jun-2007, 08:58
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
11-Jun-2007, 12:51
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
11-Jun-2007, 13:50
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
11-Jun-2007, 13:57
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
11-Jun-2007, 14:07
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
11-Jun-2007, 17:31
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!

Ben Chase
11-Jun-2007, 20:29
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!

Yep - that's what it boiled down to. I needed to be sure.
One thing I did do prior to sending it to Martin was to reverse the GG and the Fresnel after focusing closely on a ruler from about 5 feet. There was definitely focus shift - I was actually surprised at the difference.

Hopefully FedEx gets the GG frame in one piece to Marflex and back :)

KenM
12-Jun-2007, 05:34
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.

You've done the right thing by sending it in - I did the same thing with mine (not Marflex, but the Canadian Linhof service center, Blazes Photographic).

I'm a bit confused by what you've said above. As Brian (I think) mentioned above, a Maxwell screen *is* a combination GG/Fresnel, and is always installed underneath a clear (or possibly lined) glass cover. So, from the user end of the camera, the installation order would be: clear class cover, Maxwell screen with the fine grooves facing the user, and the frosted side of the screen facing the lens.

It's all moot anyways, since you've sent it in.

Ben Chase
12-Jun-2007, 06:58
You've done the right thing by sending it in - I did the same thing with mine (not Marflex, but the Canadian Linhof service center, Blazes Photographic).

I'm a bit confused by what you've said above. As Brian (I think) mentioned above, a Maxwell screen *is* a combination GG/Fresnel, and is always installed underneath a clear (or possibly lined) glass cover. So, from the user end of the camera, the installation order would be: clear class cover, Maxwell screen with the fine grooves facing the user, and the frosted side of the screen facing the lens.

It's all moot anyways, since you've sent it in.

Hmm...I'm betting that's how it was installed then. The glass was clear now that I think about it. Perhaps there was nothing wrong after all? I hope that Marflex doesn't install the Maxwell combo incorrectly if that's the case.

In theory if the shims are in the proper spot, I should be able to put whatever GG type on the shim that I want. I'm more concerned about the shims being in the right spot.

Al Seyle
12-Jun-2007, 12:58
Hi Ben-
I've only just now come in on this, but since I'm the one who sold you the camera and I'm the one who installed the Maxwell, all I can say is it was installed according to Bill's instructions with him on the phone while I did it. He furnished the shims, and fasteners, too. As it was several years ago, I don't remember much more than this, but I can tell you that I never had focus issues and I was very happy with the huge brightness improvement of the Maxwell screen compared to the original Linhof. If you had not sent it to Marflex I would advise calling Bill, because it's his product--not Linhof's. But that ship has sailed.
Good luck.

Brian Ellis
12-Jun-2007, 17:55
"I hope that Marflex doesn't install the Maxwell combo incorrectly if that's the case."

Ben - I think this is a legitimate concern and if I were you I'd give Martin a call and see what he plans to do before he does it. As I mentioned before, Bill Maxwell provides some items of hardware when his screens are installed in a Linhof camera and these items are supposed to be substituted for the corresponding Linhof parts. Your camera presumably has the Maxwell parts but if not you'd want to get them from Bill Maxwell and have Martin use them. The last thing you'd want is for Martin to replace Maxwell parts with Linhof parts or to continue to use Linhof parts if that's what's now on your camera.

He may very well know all about this, he's extremely knowledgeable and capable and you're probably not the first person to send him a camera with a Maxwell screen. But I think it would be worth a phone call just to be on the safe side. I'm sorry that I can't remember exactly which Maxwell parts are substituted for the corresponding Linhof parts, I think it was the clips and the screws but I'm not sure. As I mentioned before, when I installed my Maxwell screen I didn't understand the importance of using all the parts that Maxwell sends with the screen. So I mistakenly thought I could continue to use some of the Linhof parts and totally messed up about 50 sheets of film the first time I used the camera after installing the Maxwell screen because the film holders weren't properly seated in the camera.

Ben Chase
12-Jun-2007, 21:19
"I hope that Marflex doesn't install the Maxwell combo incorrectly if that's the case."

Ben - I think this is a legitimate concern and if I were you I'd give Martin a call and see what he plans to do before he does it. As I mentioned before, Bill Maxwell provides some items of hardware when his screens are installed in a Linhof camera and these items are supposed to be substituted for the corresponding Linhof parts. Your camera presumably has the Maxwell parts but if not you'd want to get them from Bill Maxwell and have Martin use them. The last thing you'd want is for Martin to replace Maxwell parts with Linhof parts or to continue to use Linhof parts if that's what's now on your camera.

He may very well know all about this, he's extremely knowledgeable and capable and you're probably not the first person to send him a camera with a Maxwell screen. But I think it would be worth a phone call just to be on the safe side. I'm sorry that I can't remember exactly which Maxwell parts are substituted for the corresponding Linhof parts, I think it was the clips and the screws but I'm not sure. As I mentioned before, when I installed my Maxwell screen I didn't understand the importance of using all the parts that Maxwell sends with the screen. So I mistakenly thought I could continue to use some of the Linhof parts and totally messed up about 50 sheets of film the first time I used the camera after installing the Maxwell screen because the film holders weren't properly seated in the camera.

I spoke to Martin today and he seemed very familiar and recognized that it was a Maxwell screen. He explained that these are outstanding screens, (which I know from using it), and that the clear glass is installed over the top of the actual screen, since the screen is both a fresnel and a GG.

When I get the camera back, I will take some wide-open test shots and have them developed, as well as call Bill Maxwell to see if there is anything left that I need to do.

I asked him specifically if he was 100% sure that the screen was installed properly and the shims were where they were supposed to be. He said "absolutely".

Ben Chase
14-Jun-2007, 21:36
I spoke to Martin today and he seemed very familiar and recognized that it was a Maxwell screen. He explained that these are outstanding screens, (which I know from using it), and that the clear glass is installed over the top of the actual screen, since the screen is both a fresnel and a GG.

When I get the camera back, I will take some wide-open test shots and have them developed, as well as call Bill Maxwell to see if there is anything left that I need to do.

I asked him specifically if he was 100% sure that the screen was installed properly and the shims were where they were supposed to be. He said "absolutely".

Got the GG back from Marflex today. He reinstalled the Maxwell correctly, and replaced the two missing center screws on the back. He also noted that he did have to make a slight adjustment to the shims to take them back to the Linhof factory spec, which is 4.85mm, according to the work order he gave back to me today.

I'll make some test shots tomorrow and get them developed to make sure all is well. Perhaps giving Bill Maxwell a call would also be a good idea.

Michael Kadillak
14-Jun-2007, 21:52
Perhaps giving Bill Maxwell a call would also be a good idea.

Nothing against Bill Maxwell as he is a saint of a man that has contributed greatly to photography (I have his screens on several cameras and thay are great) but now that you have your ground glass assembly back from Marflex your problem is solved and you need to resist any urge to mess with it EVER. Mark this in the category of experience and go out and make photographs.

Cheers!

Ben Chase
18-Jun-2007, 19:28
Nothing against Bill Maxwell as he is a saint of a man that has contributed greatly to photography (I have his screens on several cameras and thay are great) but now that you have your ground glass assembly back from Marflex your problem is solved and you need to resist any urge to mess with it EVER. Mark this in the category of experience and go out and make photographs.

Cheers!

Actually my problem is not solved.

I took a few test shots, and they were all off focus. Reading these previous threads, it appears now that the shims were replaced by Al as part of the installation of the Maxwell screen.

Looks like Marflex didn't recognize that the shims were not Linhof factory shims, and he adjusted them to 4.85 mm (which apparently is factory spec). Well - naturally this wouldn't work, as the shims supplied by Maxwell clearly aren't the Linhof shims.

So in the morning I'll be calling Marflex to have them completely replace the shims with Linhof ones and install a new Linhof-brand groundglass. I'm tired of screwing around with this.

After speaking with Martin on the phone after he adjusted the shims, I certainly got the impression that he was extremely familiar with the Maxwell screen, but it seems pretty clear to me that he didn't know about the shims.

Looks like my Glacier trip will be pushed back a week, unless I can get quick turnaround on this.

tim atherton
18-Jun-2007, 20:00
Unfortunately I could see this coming.

You would have probably been better off talking just to Maxwell as Brian suggested and forgetting Marflex

Ben Chase
18-Jun-2007, 20:46
Unfortunately I could see this coming.

You would have probably been better off talking just to Maxwell as Brian suggested and forgetting Marflex

Yeah, problem was that I already had it in the mail.

At least now, if it's restored completely to factory spec, the only variable in the equation that I have to worry about is me.

Lesson learned.

Michael Kadillak
18-Jun-2007, 21:18
Actually my problem is not solved.

Looks like Marflex didn't recognize that the shims were not Linhof factory shims, and he adjusted them to 4.85 mm (which apparently is factory spec). Well - naturally this wouldn't work, as the shims supplied by Maxwell clearly aren't the Linhof shims.
.

I don't see why where the shims were made has any bearing on solving this problem because shims do one simpe task - they fill voids. Sounds like Marflex made a mistake attempting a solution and they should make it right. However this system came together it was not working and that is unacceptable.

When I have a problem with a camera I use the factory trained service rep to resolve it. After market accessories that go on cameras that require ground glass alignment can be a PITA particularly when these accessories are acquired in the used market because you just do not know the details of their installation. Nothing against Maxwell screens as I understand that Keith Canham uses them on his camera line and accepts the responsibility of their performance.

Putting on a straight ground glass will set you straight. You always have the option of the behind the ground glass fresnel offered by Linhof as this can be put on and taken off without any risk of focus control.

Onward!

tim atherton
18-Jun-2007, 21:22
Putting on a straight ground glass will set you straight. You always have the option of the behind the ground glass fresnel offered by Linhof as this can be put on and taken off without any risk of focus control.

Onward!

However, I switched from the Linhof fresnel setup to a Maxwell screen on my Technikardan and it is siginificantly better - worth the slight fiddling with installation

Mattg
18-Jun-2007, 21:40
Get ready for a shock Ben, the Linhof ground glass is going to seem a little dim... At least you will be able to have confidence in the placement of the glass for your trip.

I recently had a TK23S out on approval and the sole reason I decided not to buy it was the very dim groundglass and the potential problems in replacing it. It's a pity you don't have more time to have it fixed, I'm pretty sure Billl Maxwell would have fitted his screen for you.

Ben Chase
18-Jun-2007, 21:51
Get ready for a shock Ben, the Linhof ground glass is going to seem a little dim... At least you will be able to have confidence in the placement of the glass for your trip.

I recently had a TK23S out on approval and the sole reason I decided not to buy it was the very dim groundglass and the potential problems in replacing it. It's a pity you don't have more time to have it fixed, I'm pretty sure Billl Maxwell would have fitted his screen for you.

I'm not opposed to sending my GG frame to Maxwell if I can get a very fast turnaround time, and if he could absolutely guarantee that the focus plane is as perfect as mechanically possible. Tim, anyone - Have his number?

It could be that I'm being overly paranoid, and I made an error while doing my tests.

Is there a reliable test I could replicate that would pretty much guarantee that my groundglass is in fact installed correctly?

Sheldon N
18-Jun-2007, 21:59
Is there a reliable test I could replicate that would pretty much guarantee that my groundglass is in fact installed correctly?

http://photo.net/learn/focustest/

This test stems out of the digital "back focus" craze, but works equally as well for LF film. Shoot B&W with a couple different lenses, perhaps even two sheets per lens refocusing between shots, develop yourself, and scan at high resolution to check for whether your focus is consistently front or back.

If you are consistently front focused (focused too close) then you need to shim the glass away from the back of the camera. If you are consistently back focused (focused too far away) then you need less shim.

If you aren't consistently front or back focused, then its you that's the problem. :)

tim atherton
18-Jun-2007, 22:19
this was the last info I had (can't find the pritned stuff right now)

http://www.mattclara.com/maxwell/index.html

click on contact for the phone number

Ben Chase
19-Jun-2007, 08:55
Can't seem to get him to answer the phone, and I've left a message and sent an e-mail.

I'm going to hold off mailing anything today.

I spoke to Martin at Marflex today, and he seems pretty insistent that the shims that were in my groundglass back are Linhof original shims.

Based on what Al said below, it seems as though the shims and God knows what else have been replaced in the GG back. I can't get Martin to understand this fact and he won't guarantee that he'll replace the shims, screws, and whatever else if I send the groundglass back to him, but instead he'll only replace the groundglass if he finds the shims are what he considers to be factory. In essence, he's challenging Al's statement that the shims were ever replaced, which I don't understand at all.

Ben Chase
19-Jun-2007, 11:35
Got in touch with Bill. I sent him my groundglass.

Real nice guy, and you guys were right about him loving to talk about everything photographic. I had to recharge my Blackberry after that conversation.

Now if I only would have sent this thing to him in the first place.....