enlarger conversion

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I have just purchased what looks like an old copy camera from the basement of a used furniture store. I'm hoping to convert it into an enlarger. I'd first like to ask if anyone out there has heard of the make and manufacturer. It's called a Technifax Photo Modifier, made by M.P. Goodkin. The bellows opening at the top of the camera is 13''x15'' and has extension of 26''. The lensboard and bellows ride up and down a column by chain. A ground glass covers the opening at the top of the camera with a hinged hatch door that closes down tight over the opening. I'm planning to use enlarger horizontally. My questions are: 1. What would I have to do in order to convert this into an 8x10 enlarger? 2. With a bellows this wide could I conceivably enlarge an 11x14 negative? 3. What focal length of enlarging lense would I need? Is older glass ok? 4. What kind of light source could I make?

I'd be grateful for any tips. thakyou

-- Colin Seaman (cbsea@hotmail.com), April 12, 1999


Your prospective setup sounds a lot like what Ansel Adams used to build his 8x10 enlarger. There are some decent shots of it in "The Print" and he discusses building an 8x10 enlarger a little.

There are also some details on the homemade light source he used before going to cold light. It's a square tungsten bulb array.

Lenses? There's been some chat lately about long process barrel lenses being for sale cheap... but I couldn't help you with coverage.

-- John O'Connell (oconnell@siam.org), April 13, 1999.

I just bet it will print a 11x. Process lenses should cover also since most are used in the printing industry (mainly newspapers) they are huge but you won't have to "soup up" the lensboard and front standard like adams' model if you were converting a camera so go for a process lens. The light source is a tough one...The only problem with Adams' array is uneven illumination but you still have several other options open to you...You might be able to find a used light source and condensors or you could contact aristo and see if they build anything that large for other purposes then try to adapt or build a conic diffuser for it or maybe you could build a large single element halogen source and try to find or build something to work as a mixing chamber( maybe a large diameter section of PVC and plexi like that from a light table may be too diffuse though). You may need a machine shop but definitely a drill press and grinder and chop saw. You need to read up on stabilizing the power source and cooling the bulb too. If you need an 8x immediately I'd probably go with the pre-built aristo then you'd have an idea as to what it would take to scale that up to an 11x. I envisioned my homebuilt horizontal as a junker 8x view cam bolted to a metal tool chest(plenty of storage) on locking/leveling casters that projected on a wallboard made of 1/8" sheet steel with all-thread legs so that it could be leveled to the enlarger but I've since decided to save up and buy an old omega f or devere monster and knock out a hole in the ceiling of my garage... it will probably be cheaper in the long run. Is this a big copy cam on a track with a copy board on the other end or is it vert like a vert enlarger. I'm trying to see it.

-- Trib (linhof6@hotmail.com), April 14, 1999.

Goodkin made copy cameras for printers. That sounds like what you have, minus lights and vacuum back to hold the film. Should make a fine enlarger. If it has some counter dials on it, they used to be for setting enlargement or reductions. Aristo Grid Lamp Products make large contact printers (11 x 14) and may be able to supply a cold light to fit your machine. A 12 to 14 inch process lens should work fine.

-- Tony Brent (ajbrent@mich.com), April 14, 1999.

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