Where do I get universal 4x5 ground glass?

February 17, 2013 1:42 PM

I've got this image of a piece of ground glass mounted in a standard 4x5 film holder. I've googled all sorts of things to try and describe what this is, but I cannot find where I can buy this. I've seen tons of pieces of ground glass that are for specific cameras, but that's not what I want. I want a piece of ground glass in (and sold with) a frame that makes it the exact size and thickness for putting into any sort of large format camera. Basically, what that picture shows. What is this and where do I buy it? Thanks!
posted by Brian Puccio to shopping (27 answers total)

I think what you're looking for is called a focusing panel.
posted by pullayup at 2:01 PM on February 17

AKA focusing screen
posted by run"monty at 2:04 PM on February 17 [1 favorite]

It's been a while, but I think the camera back you're talking about is "Graflok" style (after the Graflex cameras, which introduced it) or an "international (spring) back". Specifically, you're looking for the ground glass focusing insert, which is removed and replaced with the film holder after you've focused.
posted by pullayup at 2:20 PM on February 17

I'm not sure what you're looking for actually exists, and if it does, is still produced today. Your best bet may be to just repurpose a film holder like in the photo you posted. What kind of camera(s) are you using that would require such a holder?
posted by Venadium at 3:45 PM on February 17

From what I understood, it seems like he's not looking for a back, Graflok or otherwise, to mount on the camera as you normally would, but instead some kind of frame for the ground glass so it can be inserted where the film holder normally would be. Of course, usually the film holder is inserted under some kind of spring back which already includes a piece of ground glass, but theoretically this would be the most precise way to make sure your film ends up on exactly the same plane as the glass you're focusing on.
posted by Venadium at 3:57 PM on February 17

pullayup: I think what you're looking for is called a focusing panel.

eBay only shows one item, auction 111013099490, but this looks far too large.

run"monty: AKA focusing screen

That term lets me find a bunch of things like ebay auction 180958926527 and ebay auction 280625859173, but nothing that will simply slide in where I would normally slide in my film holder.

Searching by this term (and the term pullayup mentions) doesn't let me find the item I've posted an image of, which is a universale insert that would slide in where the film holder would go. The thickness would be just right so the front of the ground glass would be exactly where the film would be, ensuring that on the GG meant that the focus would translate to film.

pullayup: It's been a while, but I think the camera back you're talking about is "Graflok" style (after the Graflex cameras, which introduced it) or an "international (spring) back". Specifically, you're looking for the ground glass focusing insert, which is removed and replaced with the film holder after you've focused.

No, sorry, those terms haven't helped either.

I've searched for graflok ground glass, graflok focus insert, graflok slide in ground glass, 4x5 ground glass slide in, universal 4x5 focus, universal 4x5 ground glass, etc, etc. I cannot find anyone selling what I've posted an image of nor the proper name for it.

Venadium: I'm not sure what you're looking for actually exists, and if it does, is still produced today. Your best bet may be to just repurpose a film holder like in the photo you posted. What kind of camera(s) are you using that would require such a holder?

I'm afraid it does not.

I have a feeling I'm going to need to take the most precise measurements I can before tearing apart a film holder. I'm just worried about making a slide-in universal 4x5 ground glass that wouldn't exactly match where the film plane would be. (Thus, rendering every photograph out of focus.)

I'm building a P&S 4x5 with a Schneider 90mm f/5.6, helical and 3D printed "cone" (a la fotoman) that takes 4x5 film holders on the back end. (After looking over my Harman Titan pinhole, the receiving end for the 4x5 film holders doesn't look complex at all to make light tight.) I'm just looking for a method to get the GG in with as little hassle as possible so I can confirm various focal distances so then I can scale focus. (I normally shoot with an M6, so I can use the rangefinder in that for whenever I don't just want to be at hyperfocal. If I like the 4x5 a bunch, I'll get a shoe-mount rangefinder and viewfinder.)

Thank you all for your help!
posted by Brian Puccio at 4:00 PM on February 17

Hmm. Now that you mention it, the ground glass is obviously going to be a whole lot thicker than a single sheet of film would be, so just sliding one into a film holder with the center removed isn't going to do the trick. It's an interesting project though, and if you haven't already done so, you could probably get a whole lot more help from the people over at the LFP forums: http://www.largeformatphotography.info/forum/forum.php
posted by Venadium at 4:10 PM on February 17

As you note above, the image is literally a film holder that someone slid a piece of ground glass into. They probably had to cut out some of the internals to make it fit. If you want to do this, you only need to find a piece of ground glass which is equivalent in size to a 4x5 negative. And, you're right that it isn't likely that the ground surface would fall perfectly in line with the plane of the film in the same holder--you would probably have to carefully shim it into the correct position. Also, I suspect that the piece of ground glass in your picture may not necessarily intended as a camera focusing screen (though plain ground glass is certainly available)--it's lacking the alignment grid and film size markings. If you miss them, I've heard of people literally penciling them in with a ruler, or printing a grid out on a sheet of acetate. More critically, it is probably also missing the fresnel lens which is also usually integrated with--well, taped to--the ground glass. Without the fresnel lens, the image in the ground glass will become dim near the edges, and you'll need to shade it more aggressively, with a field screen or black cloth, to be able to focus in bright light.

Assuming your back is a Graflok type, your problem is that focusing panels are usually just sold along with the whole back (e.g. eBay auction 111013851347, focusing panel is visible as a separate piece in the first photo). You may have to haunt eBay for a little while to find one. This is the correct item in the wrong size (it's 3.25" × 4.25").
posted by pullayup at 4:32 PM on February 17

And good luck, this sounds like an interesting project!
posted by pullayup at 4:39 PM on February 17

Really wish I could help directly, but I can't. Until I saw your picture I had no idea I wanted one of these, but now I do. Of course - it would have to be very well made, since the ground glass side would have to be EXACTLY on the film plane for it to be on any use.

There are a few forums on the web that have a lot of large format traffic, you can try one of them.
photo.net
largeformatphotography.info
APUG
posted by RustyBrooks at 8:35 PM on February 17

BTW this is clearly a custom job - Lisco Regal is just a really common brand of film holder, and I am 99.9% sure they never made anything like this.
posted by RustyBrooks at 8:36 PM on February 17

Here's a guy who's at least partially made one of these
posted by RustyBrooks at 8:45 PM on February 17 [1 favorite]

Pretty thin but here's a dude who did it

My search method here, btw, is to do google image searches for like "ground glass film holder" or "film holder with ground glass to focus" or something like that. GIS is really good for things that you "know them when you see them" but that are hard to put into words.
posted by RustyBrooks at 8:51 PM on February 17 [1 favorite]

I'm confused. Why can't you just pull the ground glass assembly(including the frame) out of a spare back and use that? Why does it have to be a film holder? The assembly out of an old graflok back would work perfectly.
posted by mockpuppet at 4:10 AM on February 18 [1 favorite]

Why can't you just pull the ground glass assembly(including the frame) out of a spare back and use that?

The whole poing here is that you use the ground glass back to focus, and then you shove a film holder with film into the back. You assume/hope that the film ends up in the EXACT same place that the ground glass was on your back, so that the picture gets taken in focus. But if your back is messed up in some way, the film plane could be in a different place.

If instead you took the glass out and shoved one of these babies in there, then you'd be looking at a ground glass more or less guaranteed to be in the exact sample plane the film would go in. You could evaluate whether or not your GG was good.
posted by RustyBrooks at 7:12 AM on February 18

Why can't you just pull the ground glass assembly(including the frame) out of a spare back and use that?

[...] You could evaluate whether or not your GG was good.

Hence the caption on the original picture: "The only accurate way to check if your ground glass tells lies..."
posted by pullayup at 9:33 AM on February 18

That said, it sounds like the OP's camera project has no ground glass at all, and one of these isn't really intended as a replacement. If he has the "camera half" of a Graflok back, the missing focusing panel/screen also serves to hold the film holder in place--it has two spring loaded arms which "lock" to the camera's back, and these press the film holder between the screen and camera while you make your exposure.

If his camera does have half of a Graflok back already, he still needs the screen frame (with ground glass removed) to use one of these.
posted by pullayup at 9:54 AM on February 18

And if he doesn't have that, he doesn't have a working camera at all really, since you wouldn't be able to put a film holder in it, right?
posted by RustyBrooks at 9:58 AM on February 18

Well, he mentions that "3D printed "cone" (a la fotoman) that takes 4x5 film holders on the back end" so it's not clear if his camera has a Graflok back at all--it could just have a slot for a film holder. This wouldn't be the most versatile camera back, but it would certainly work, if you can make it light-tight.

A Graflok/international back was my guess because it's as close to being a "generic" 4x5 back as exists, and he complained about only finding proprietary parts. If I were 3D printing a camera body, I would design it to accept existing backs, because they're intended to be interchangeable, are widely available, and run $50-$150 on eBay. That's around what Fotoman charges you for an adapter which you can use to mount your own back onto their camera.

I mean, it sounds like he knows what he's doing, but it also sounds like he might have to make his own focusing screen.
posted by pullayup at 10:28 AM on February 18

Thank you all so much for your help. To be honest, my only experience with large format photography is the Harman Titan pinhole. It's a cheap plastic "cone" with a pinhole at one end and a slot for 4x5 film holders on the other. I've never touched a large format camera, I've just spent the past few months researching. I figured 3D printing a cone that would have a large enough hole for a lens with helical and the same slot for 4x5 film holders shouldn't be too hard. I'd just have to leave room to shim to fine calibrate the focusing, which I'd like to do with ground glass. (As opposed to burning through film.) I just kind of assumed that they made these sorts of ground glass in a film holder so it fits any 4x5 camera things and that I didn't know what they were called.

Oops. :/

I mean, it sounds like he knows what he's doing ...

I'm glad I've got you all fooled.
posted by Brian Puccio at 7:08 AM on February 19

I like fooling with impractical stuff as much as the next guy, but FYI, if you want a real honest to goodness 4x5 camera they are *super cheap* now. Like, 100-200 bucks will get you something very usable, and you can probably get about everything you need for 200. I recently bought a pretty nice Calumet Cambo 4x5, with 2 nice lenses (90mm and 210mm), 8 film holders, dark cloth, shutter release, hard case for something like $225.

(As a bonus, it came with some expired but discontinued polaroid film and a polaroid holder for it. These by themselves appear to be worth more than the camera)

The only reason I bring this up is that if you're looking for a cheap entrance to 4x5 you probably aren't going to be able to beat ebay right now.
posted by RustyBrooks at 1:20 PM on February 19

And if you want something a bit more portable, you can look into stuff like the Speed Graphics and what not. I don't know exactly what they go for but reasonably cheap.
posted by RustyBrooks at 1:23 PM on February 19

Ok for the record, I use 4x5 and 5x7 cameras almost exclusively, and I'm still pretty sure that what you are looking for is the ground glass assembly from a 4x5 camera. Basically this is exactly what the ground glass does, it puts the glass in the plane of the film, so you can focus on the ground glass. So...I would not mess around with a film holder or trying to make something that mimics the plane of the film holder. That's what the ground glass assembly does.

For instance, this on ebay. Too expensive and you might find just the focusing panel and not the whole back, but still much easier than trying to cobble together a DIY solution.
posted by mockpuppet at 2:23 PM on February 19

mockpuppet, imagine a camera that doesn't have a place to put a back at all, just a slot you slide a film holder into. Like, check out his link to the Harman Titan pinhole. It's basically just got some guides you slide a holder into. Fine for a pinhole.

He's imagining finding or making a similar camera but one with a lens and a primitive focusing mechanism. It won't have the connections to attach a graflex back. In this case, using a film holder with a GG right at the film plane would definitely be the way to go.

But if you're making your own, you'd want something that took some kind of standard back attachment, just for ease of finding parts. The graflex/graflok is pretty much the standard there, sure.

Here's an good picture of what he's dealing with
posted by RustyBrooks at 5:40 PM on February 19

Yup. You can put the focusing panel in there. If you are worried about holding it in you could use rubber bands or something like that. Again, that's what the focusing panel does. It suspends the ground glass in the position of the film plane. It can be removable or sprung.
posted by mockpuppet at 8:05 PM on February 19

I mean jeez, this ends in 25 minutes and is going for under $120:
http://www.ebay.com/itm/Calumet-C1-4x5-View-Camera-w-Case-/221189903259?pt=Film_Cameras&hash=item337ff2139b
Calumet 4x5 camera. Very capable camera.

I guess if you stripped all the extra crap off the GG holder it might fit in the back - I feel like mine is wider and longer than a film holder though. I'll check later.
posted by RustyBrooks at 8:15 AM on February 20

I guess if you stripped all the extra crap off the GG holder it might fit in the back

yup. it has to. That's what it does.
posted by mockpuppet at 10:20 AM on February 20