Photo Notes A place to talk about making images.

March 27, 2019

Lens Board Hacks for Large Format Cameras

I’ve been teaching people about view cameras for a long time. I used to tell people it was like a cross between an erector set and a camera. You can put it together in whatever way you want. I also used to tell them that it was a simple camera; the thing is simple doesn’t mean easy. An ax is a very simple tool, but if you need to cut down a tree, I guarantee you that a chain saw, while more complex, will be easier…

 

The view camera is essentially three parts, the lens, the bellows and the film holder. The rest of the camera is there to make it possible to fit these parts together in the best position for a specific photograph. I’m going to be discussing how the lens is mounted on the camera in the rest of this post. Almost any lens will fit on almost any view camera. Brands don’t matter because lenses are fitted to boards which fit specific cameras. There are no electrical contacts, rangefinder cogs or complex bayonets in this system, only rectangular boards. These boards are designed to fit on a camera so that no light can leak around the board. Many recent manufacturers use metal boards with a sort of lip that fits the camera, but may versions have been used over the years. This s the problem: most cameras use a board that only fits that brand, or at most a couple of brands, of camera. In fact, many camera companies use different boards for different model cameras. While this doesn’t mean that you can’t exchange lenses between different cameras it does become a pain in the neck. In order to mount a lens on a different board you generally have to unscrew the rear elements and remove the retaining ring before you put it back together on another board fitted to that lens.

 

If you only have a couple of lenses and a couple of cameras this isn’t intolerable, but for me it’s getting out of hand. I have a couple of dozen lenses and five cameras I might use them on. Since each lens might be used with any of the cameras this can mean a lot of lens boards. I’m not the first person to create conversion boards, in fact, many of the camera companies build boards to fit boards from other cameras. However, a couple of my recent cameras, my 11X14 and 8×20 camera, are older and no conversion boards exist. Also my main lens boards, the 6X6 inch Toyo board, is too large to easily fit to these cameras. To compound the problem these two cameras don’t take the same lens board. So, I want to show you how I solved this problem. In addition I want to show you a way to use lenses that don’t have a retaining ring and lenses that don’t have a shutter.

 

The basic plan, which I’ve illustrated below, is to take a lens board that fits the new camera and attach it to a lens board that fits a Toyo camera. You’re going to put them together front to front, with a little space between. The space allows for the boards to be connected to the camera. Then you can take the center piece of the front standard and mount it to the Toyo board. Since the standards on Toyo cameras, and several other cameras, are the same on both the front and back this works well to give a place to attach any lens mounted on a Toyo board. I should also point out that the standards on Toyo cameras, at least older ones, are pretty fragile, so it’s possible to get the part you’ll want off a broken camera.

THIS PROCESS REQUIRES POWER TOOLS. BE CAREFUL. USE EYE PROTECTION. IF YOU HAVEN’T USED THESE TOOLS BEFORE PRACTICE ON UNIMPORTANT MATERIALS.

01: This shows my new Korona 8X20 camera. The lens board I’m converting is mounted on the camera.

 

02: The wooden lens board for the Korona and a metal Toyo board. I want the Korona to take Toyo boards.

 

03: After I’ve outlined the hole I want; I drill holes around the edge of the hole. These holes make it easier to control the Dremel tool.

04: The Dremel set up. The bit cuts to the side. The black collar makes it easier to control the Dremel tool. BE CAREFUL, the Dremel is tricky to use.

05: Cutting the hole with the Dremel tool.

06: I use the hole in the wood lens board to size the hole in the Toyo board.

07: I’ve used the same process as I did on the wood lens board. Holes first then the Dremel too. The metal board is more difficult to cut than the wood board. BE CAREFUL-USE EYE PROTECTION!

08: The metal board has sharp edges. I’ll use the Dremel to sand them smooth

09: I’ve drilled holes in the edges of the Toyo board. Then I’ll use those holes to drill hole for the bolts into the wood lens board. I’ve placed washers in the space between the boards. If you just screw the two boards together you won’t have space to mount them on the camera.

10: I’ve assembled the two boards. I’ll check this assembly on the camera Before I Glue The Parts!

11: I’ve put a bead of the glue onto the wood board. I use Ultra Black Gasket Maker Glue. Basically it’s black silicone sealer.

12: I’ve put the glue into the gap. Use a lot of glue. You don’t want light leaks. This is a messy step.

13: This is the part I salvaged from a broken Toyo standard. I had to fill a couple of screw holes with the same Ultra Black Gasket Maker Glue. I use the same part on my 11×14 camera.

14: the assembly mounted on the 8×20 Korona camera.

15: My Schneider 270mm Wide Angle G-Claron f6.3 mounted onto the camera!

View camera lenses are connected to lens boards with a threaded ring machined on the outside of the lens. These threads mate with a ring called a retaining ring. This is a simple system which works well until the retaining ring is lost. If all these retaining rings had been standardized to just a few sizes losing a ring might not be a problem. Unfortunately there are at least dozens of different widths and thread counts and pitches, so it’s impossible to just order a replacement. Generally you’ll have to have a new retaining ring custom machined. This is expensive; if you can find a machinist with the needed skills. However there is a fix! Many years ago, a sort of universal lens holder was made. This used a variable diaphragm, like the aperture in a lens. These diaphragms were made with very stiff blades, which could be locked in place. These are generally available at eBay, but they are pricey. Expect to pay from $200 to $500 for a good one. You want to be careful to check how large and how small the diaphragm adjusts, so you can be sure it will fit as many lenses as possible. Use terms like adjustable large format lens diaphragm to find one on eBay. Keep in mind that you need to be sure the lens is probably seated and locked in place before you put the lens on your camera.

A1: The lens mounting diaphragm on the camera.

A2: An old brass lens on mounted to the 8×20 camera.

In addition to lenses that don’t have a retaining ring there are also a lot of lenses that don’t have a shutter. Of course you can use a lens cap if you’re working with a long exposure, but if you want more choices it’s good to have a shutter. You can have a machinist install your lens in a new shutter, but this is quite expensive and requires a very good machinist. If you have as many old lenses as I do this can be a daunting prospect. There is a way around this problem as well, but it isn’t as controllable as a modern leaf shutter. The solution is a Packard shutter. Strangely enough these are still being made! You can find a new shutter at packardshutter.com, or you can find used ones on eBay. These are air driven shutters, which means that they’re powered by an air bulb that you hold in your hand. In fact these air bulbs are the reason that most shutters have a B setting, b stood for bulb. With these shutters you can hold the shutter open as long as you want, or open and close the shutter in about 1/20 of a second. It’s important to stress that that fast speed is extremely variable. These shutters are often mounted inside a large view camera or on the back of lens boards. I’ve arranged one to fit on the front of a Toyo compendium lens hood. This works very well for a couple of reasons, first I can use a very large Packard shutter that wouldn’t fit into my camera. Second, I can use the same shutter with several cameras. The compendium lens hood protects my film from being exposed by light from the side of camera. It’s also nice that the compendium hood fits onto the part of the front standard that I used as my lens board converter! This means that I can mount the same shutter assembly on several cameras, including some that are quite old.

B1: The Toyo standard has mounting holes for a compendium lens shade. The shade is mounted in this shot.

B2: I’ve moved the compendium shade in front of the lens. I put magnetic strips on the front of the shade. These strips are holding the Packard shutter in this shot.

B3: The Packard shutter is open in this shot. Now I can use the Schneider G-Claron on the camera!

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