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abruzzi
9-Jun-2019, 07:30
I just received my first LF camera yesterday—a Linhof Technika IV purchased from KEH. After doing some test shots yesterday evening I came to the conclusion that I probably need a fresnel screen to improve the illumination.

(With a cover the screen is plenty bright enough to get close and focus, but when I step back, the light fall off from the center makes it really hard to compose.)

My googling has suggested that there were fresnels that go between the screen and the lens (a permanent installation) and screens the go on the outside and can be removed. It seems to depend on what back I have on the camera.

Also, having spent all my money getting the camera and necessary gear to use the camera, I’m a bit broke, so I’m also wondering what third party options there are?

Bob Salomon
9-Jun-2019, 07:38
The IV used the Fresnel beneath the gg. That means that the position of the gg has to be adjusted accordingly.
Since you have bought a very old camera you have no way of knowing if your gg is properly positioned for a Fresnel or not.
If it is not adjusted for a Fresnel then you can just call Linhof Service (Bob Watkins) and order a pair of Fresnel clips and screws. Then you remove the center screw on the gg hold down clips at either end of the gg and replace the screws with the Fresnel clips and the screws. Then you slide the clips to the side and drop the Fresnel on top of the gg and slide the clips down.
If your camera has a gg positioned for a Fresnel and it is missing then you would have to send it to service to have the Fresnel installed and the gg properly positioned.

In either case you would find the current gg a great improvement over the older ones.

ic-racer
9-Jun-2019, 07:40
If 'broke' try this for less than ten dollars.

Mine is held to the camera by the ground glass clips, with no modification to the camera.

192230

192231

Bob Salomon
9-Jun-2019, 09:05
If 'broke' try this for less than ten dollars.

Mine is held to the camera by the ground glass clips, with no modification to the camera.

192230

192231

This won’t do any good if the gg is not properly positioned. It also may be the wrong focal length for most lenses on the camera.

abruzzi
9-Jun-2019, 10:58
If your camera has a gg positioned for a Fresnel and it is missing then you would have to send it to service to have the Fresnel installed and the gg properly positioned.

There are no clips for the GG in front of the screen that I can see. Is there any way to tell if the position of the GG has been adjusted for a fresnel?

Also, I’m a little confused—in some cases the fresnel goes behind the GG (your first statement) and in some cases it goes in front (the clips you mentioned.) Is the position of the GG different in each scenario? Are those two positions different than if there is no fresnel (like now.)

Also, as another option, I found this:

https://www.ebay.com/itm/New-Linhof-Super-Technika-4x5-Camera-Fresnel-Lens-Ground-Glass-Best-quality/223195084337?hash=item33f776b631:g:b-AAAOSwfjVbyRS1

This seems to be an acrylic GG with built in fresnel. Under which circumstances would this work? Would I need the GG positioned as if no fresnel was installed, rear or front fresnel position?

I’m sorry if these are stupid questions, I’m new to this, and while I know the GG needs to be positioned at the film plane, I don’t know what effect the fresnel has on that.

Bob Salomon
9-Jun-2019, 11:19
There are no clips for the GG in front of the screen that I can see. Is there any way to tell if the position of the GG has been adjusted for a fresnel?

Also, I’m a little confused—in some cases the fresnel goes behind the GG (your first statement) and in some cases it goes in front (the clips you mentioned.) Is the position of the GG different in each scenario? Are those two positions different than if there is no fresnel (like now.)

Also, as another option, I found this:

https://www.ebay.com/itm/New-Linhof-Super-Technika-4x5-Camera-Fresnel-Lens-Ground-Glass-Best-quality/223195084337?hash=item33f776b631:g:b-AAAOSwfjVbyRS1

This seems to be an acrylic GG with built in fresnel. Under which circumstances would this work? Would I need the GG positioned as if no fresnel was installed, rear or front fresnel position?

I’m sorry if these are stupid questions, I’m new to this, and while I know the GG needs to be positioned at the film plane, I don’t know what effect the fresnel has on that.

1: older cameras, yours, the factory placed the Fresnel under the gg. No clips were used.
2: later cameras have the Fresnel placed on top of the gg held in place with hold down clips.
3: visually you can not tell if your camera has been adjusted for the Fresnel under the gg unless the Fresnel is still there.
4: if there is no Fresnel under your gg then you need the service center to check your gg placement in case it is adjusted for the missing Fresnel.
5: it might work if the shims that your gg are adjusted for no Fresnel under the gg as the one you found functions as both a Fresnel and a gg.

Your best solution is to have service determine how your gg placement is adjusted.

As your camera was made between 1956 and 1963 it is probably overdue for a proper CLA anyway as 63 years old to 56 years old is a long way to go without one!

abruzzi
9-Jun-2019, 15:17
While I’m aware that a CLA is probably in order, I’m not sure it is in the budget. As my very first LF camera, I was hoping to actually learn to shoot it (and decide if LF is for me) before sinking more money into it. Is this an issue limited to Linhofs, not being able to determine myself whether a camera is good or not? I can return the camera to KEH. They have a Ikeda Anba wooden folding camera for the same price as the Linhof, and a Wista and Toyo for just a little more. I bought the Linhof because it seemed like a better camera for the money.

Bob Salomon
9-Jun-2019, 15:28
While I’m aware that a CLA is probably in order, I’m not sure it is in the budget. As my very first LF camera, I was hoping to actually learn to shoot it (and decide if LF is for me) before sinking more money into it. Is this an issue limited to Linhofs, not being able to determine myself whether a camera is good or not? I can return the camera to KEH. They have a Ikeda Anba wooden folding camera for the same price as the Linhof, and a Wista and Toyo for just a little more. I bought the Linhof because it seemed like a better camera for the money.

If you just want to use a 45 on a tripod you don’t need a rangefinder. If you want to do handheld 45 you need both a rangefinder and a viewfinder.

If you want to use any view camera you need to know that the gg is properly positioned.

abruzzi
9-Jun-2019, 17:35
Right, I have no interest in handheld/rangefinder, I just find it surprising that it seems like there is a factory modification, but there is no information out there on how to determine if the modification has been done.which means, short of spending $X to send it off to a service center, there isn’t way to know if the camera is focusing correctly. My couple of test shots seem ok, but at f16, it might just be depth of field. If there were a spec like “remove the gg and measure this edge with a caliper, if it’s Y, it needs the inner fresnel, if it’s Z, it doesn’t.

Bob Salomon
9-Jun-2019, 17:40
Right, I have no interest in handheld/rangefinder, I just find it surprising that it seems like there is a factory modification, but there is no information out there on how to determine if the modification has been done.which means, short of spending $X to send it off to a service center, there isn’t way to know if the camera is focusing correctly. My couple of test shots seem ok, but at f16, it might just be depth of field. If there were a spec like “remove the gg and measure this edge with a caliper, if it’s Y, it needs the inner fresnel, if it’s Z, it doesn’t.

That is a service center question. They have the specs for the camera. Bob Watson would be the right one to ask.