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cp_photo
5-Feb-2017, 11:34
Hello -

Unfortunately I now have a chip/small crack in my ground glass of my Horseman L45.

I was fumbling with it as I was attaching to roll film back and made a classic newbie mistake.

Even though it does not prevent me from using the camera, I want to replace the ground glass because it bugs me. It appears to be held in place by six screws that hold down metal clips on two sides.

How can I be certain that a replacement glass will be of the correct dimensions?
Are 4x5 ground glass sizes standardized?
Do I risk damaging correct focusing in some way by trying to do this myself?
Are the screws held in place by any type of thread locking compound?
Is this a DIY repair or not?

I see replacement ground glass for sale on the auction site for sale between $40-150. I don't see any Horseman-branded replacements. Is there a vendor who can supply me with an actual Horseman replacement?

I'm trying not to spend too much cash here, thus the desire to swap out the glass myself.

Thanks for any advice or suggestions.

cp_photo
5-Feb-2017, 11:53
I see on the web site

http://www.kenko-pi.co.jp/horseman/e/L45_sys.html that a replacement ground glass would be: Part number 23891 "4x5 ground glass".

The above Horseman page doesn't seem to offer any contact details. Is there a US retailer that might have a stockpile of "new old stock" Horseman replacement parts?

Randy Moe
5-Feb-2017, 12:23
Just use it as is. A small crack chip is nothing to worry about. Show us a picture of it.

Or make a new one DIY. Very easy and cheap. Look it up in our DIY section.

I doubt you will find a new OE Horseman GG.

You can also buy a custom new one from several sources.

Glass GG break all the time.

ic-racer
5-Feb-2017, 14:34
I was able to get new Horseman parts from KHB Photografix. They are an authorized Horseman service center. I got 90% alcohol on the fresnel of my 6x9 Horseman. The alcohol turned the plastic white. They they were able to get a new fresnel.




KHB Photografix repairs all makes and models of large format cameras, taking lenses and accessories.
We offer Factory Authorized parts and service for:
Horseman

Randy Moe
5-Feb-2017, 16:25
Speaking of fresnel, some Horseman and I don't know which, have a fresnel between the GG and lens which may or may not complicate things.

Perhaps a Horseman expert can advise on fresnel with GG and not, on a Horseman.

I do know the fresnel can affect GG focus and GG installed position.

To complicate, Sinar made their fresnel removable on the eyeball side of the GG.

cp_photo
5-Feb-2017, 16:34
It was pointed out to me that the big NYC photo retailer offers a replacement Horseman 4x5 GG for $147 as a special order item. I see others on the auction site that are Sinar or "Horseman compatible".

If one has an original replacement GG, is it safe to assume replacement is just a matter of loosening the screws, removing the existing GG, swapping in the new GG, and then tightening down the screws? Are there torque values?

B.S.Kumar
5-Feb-2017, 16:45
On Horseman cameras, the fresnel is between the glass and the lens. The fresnel is positioned so that the 'Horseman' lettering reads correctly when viewed from the back of the camera. The glass and fresnel sandwich is placed in thin holders that go on both the long sides. If the fresnel is removed the glass must be held in place with a rigid spacer in the thin holders. It is a simple matter to remove the clips and replace the glass. I have both available for sale.

Kumar

Randy Moe
5-Feb-2017, 16:48
It was pointed out to me that the big NYC photo retailer offers a replacement Horseman 4x5 GG for $147 as a special order item. I see others on the auction site that are Sinar or "Horseman compatible".

If one has an original replacement GG, is it safe to assume replacement is just a matter of loosening the screws, removing the existing GG, swapping in the new GG, and then tightening down the screws? Are there torque values?

Yes it is easy to change the GG yourself. Get good quality screwdivers that fit. THe screws are tiny, they remove easily and you lightly snug them when replacing. It's an acquired feel. Don't crank on the screws and snap them off, as it is very hard to extract broken screws that small.

Randy Moe
5-Feb-2017, 16:49
On Horseman cameras, the fresnel is between the glass and the lens. The fresnel is positioned so that the 'Horseman' lettering reads correctly when viewed from the back of the camera. The glass and fresnel sandwich is placed in thin holders that go on both the long sides. If the fresnel is removed the glass must be held in place with a rigid spacer in the thin holders. It is a simple matter to remove the clips and replace the glass. I have both available for sale.

Kumar

Not always. I have seen the fresnel on both sides. Looked OE to me.

B.S.Kumar
5-Feb-2017, 17:01
Randy, I don't know about that, but I have two Horseman cameras, and a spare back, and both have the fresnel on the inside. The screw heads are ~3.5mm Philips, not really tiny.

Kumar

Randy Moe
5-Feb-2017, 17:34
Randy, I don't know about that, but I have two Horseman cameras, and a spare back, and both have the fresnel on the inside. The screw heads are ~3.5mm Philips, not really tiny.

Kumar

I can prove my claim, but I won't.

B.S.Kumar
5-Feb-2017, 17:54
Again, I don't know about your camera.

Someone (not the OP) just asked to buy the fresnel, so I opened up the spare back. There is a very thin metal spacer at the bottom, then the fresnel and the finally the glass. The fresnel and glass are in holders on the long sides. The fresnel is also shorter than the ground glass, meaning the clips on the shorter sides won't hold it when it is screwed in place. I can't see how it would fit above the glass...

Perhaps the OP can check his camera...

Kumar

Doremus Scudder
6-Feb-2017, 03:22
I can prove my claim, but I won't.

Hey Randy,

Why not? Let's get as much information in the data base here as we can, especially about things like Fresnel screen positioning. If Horseman swings both ways, it would be good to know which models had the Fresnel on the lens side and which on the eyeball side.

@OP: You need to determine 1) if you have a Fresnel screen or not on your camera and, if so 2) which side of the ground glass it is mounted on, i.e., the lens side or the eyeballs side.

If you have no Fresnel, replacement is easy; simply get a ground glass of the right size and drop it in. Don't know about the torque specs though... :) In any case, a plain ground glass and the film should be in the same position, and the camera is so designed. The same applies for a set-up with the Fresnel screen on the eyeball side (i.e., between ground glass and viewer).

If you have a Fresnel on the lens side of the ground glass, however, the ground glass positioning is different and has been factory set for that particular combination. A Fresnel screen on the lens side shifts focus a bit from the film position, which means the ground glass/Fresnel screen sandwich has to be in a different place than the film. In this case, an OEM replacement or aftermarket one made specifically for your camera model is definitely best.


Best,

Doremus

ic-racer
6-Feb-2017, 06:12
I can prove my claim, but I won't.
You are correct, Randy. The Horseman 6x9 cameras, like the VH-R have the fresnel between your eye and the ground glass. Cameras like the FA 45 have the fresnel between the lens and ground glass.

B.S.Kumar
6-Feb-2017, 07:08
That's good to know. My statement was based on the L series 4x5 cameras I have. The OP's question was also about an L45.
Is the fresnel on the VH-R removable, like on the Sinar?

Kumar

Randy Moe
6-Feb-2017, 07:21
Perhaps I should have written, 'I cannot' as I 'should not' and 'perhaps will not' be able to reach examples off a high shelf. I await a hernia operation, as surgery won't happen for at least 6 more weeks as I worry if I will have Medicare in 6 weeks...







Hey Randy,

Why not? Let's get as much information in the data base here as we can, especially about things like Fresnel screen positioning. If Horseman swings both ways, it would be good to know which models had the Fresnel on the lens side and which on the eyeball side.

@OP: You need to determine 1) if you have a Fresnel screen or not on your camera and, if so 2) which side of the ground glass it is mounted on, i.e., the lens side or the eyeballs side.

If you have no Fresnel, replacement is easy; simply get a ground glass of the right size and drop it in. Don't know about the torque specs though... :) In any case, a plain ground glass and the film should be in the same position, and the camera is so designed. The same applies for a set-up with the Fresnel screen on the eyeball side (i.e., between ground glass and viewer).

If you have a Fresnel on the lens side of the ground glass, however, the ground glass positioning is different and has been factory set for that particular combination. A Fresnel screen on the lens side shifts focus a bit from the film position, which means the ground glass/Fresnel screen sandwich has to be in a different place than the film. In this case, an OEM replacement or aftermarket one made specifically for your camera model is definitely best.


Best,

Doremus

Randy Moe
6-Feb-2017, 07:23
That's good to know. My statement was based on the L series 4x5 cameras I have. The OP's question was also about an L45.
Is the fresnel on the VH-R removable, like on the Sinar?

Kumar

Not like a Sinar.

MartaP
6-Jun-2017, 19:19
Hello folks this is my first time in here. We got a Horseman VH-R camera and took the groundglass and fresnel lens out to clean it. We took the 4 screws out and we didn't pay much attention to two clips that were on the side. Now we are trying to put it back but can't remember where and how the clips exactly go. Can anybody in here take a photo and show it to me? Also focusing is very hard on this camera is there a way to make it brighter and easier to focus and can we work with only one glass instead of having the fresnel and the groundglass attach together? Thank you so much. Marta

B.S.Kumar
6-Jun-2017, 19:48
Hello and welcome.

I think you are speaking of U channel like clips. The fresnel/glass sandwich is held together by the clips on both the longer sides. The complete unit is placed on the frame. There ought to be two thin strips with screw holes that go on to the shorter sides. The strips are to be placed on the glass and fixed with the screws. Read above to confirm whether the fresnel is on the inside or the outside.

The fresnel makes the screen evenly illuminated by removing the hotspot. If the fresnel is on the inside, removing it will change your focus, and you should use shims to prevent that from happening.

Kumar

ic-racer
7-Jun-2017, 08:33
We got a Horseman VH-R [6x9] camera and took the groundglass and fresnel lens out to clean it. We took the 4 screws out and we didn't pay much attention to two clips that were on the side. Now we are trying to put it back but can't remember where and how the clips exactly go.

It has been almost ten years since I overhauled my Horseman VH-R, but from what I recall the most important association is the machined ridges on the assembly and the ground side of the glass have to be in direct contact. This is important to match the 4.7mm "T" distance of the 6x9 film holders (**Note different from the 6x9 rollfilm holders that fit the 4x5 camera**).

On my example, the spacers are used to keep the ridges of the fresnel lens from touching the smooth side of the ground glass. The smooth side of the fresnel is toward you eye.


LENS->Rough side of glass->Smooth side of glass-> Spacer-> Ridge side of fresnel -> Smooth side of fresnel -> EYE

The above is for 6x9 VH-R ONLY as the question was about that, realizing the original title of this thread is about the 4x5.

cp_photo
7-Jun-2017, 11:58
I was the original poster here. I managed to get a Horseman replacement GG from Kumar in Japan, and a used, complete Horseman GG and back assembly for cheap on the auction site from a US seller. The original chip/crack in my GG objectively speaking wasn't that bad anyways so I am just using it as is and am keeping the spares in case of breakage while hauling this heavy thing around. I haven't weighed it but the Horseman feels like more than 10 pounds!