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View Full Version : Fast 4x5 lens around 135-150mm, image quality not important - does it exist?



Steve Goldstein
13-May-2009, 11:56
I used my Beseler 45 as a light source for contact printing a wholeplate negative on Lodima. To do this I used a 4x5 negative carrier with a 150mm f/5.6 enlarging lens. I needed an 11 minute exposure with my V54 lamp, which was mighty boring.

There are some things I could do to cut down this time. First, I could turn up the intensity control on my Zone VI stabilizer, I've got about one stop more before it stops stabilizing (it's 1/4 stop per index mark, in case you were wondering). I can also focus the negative carrier opening more tightly on the contact printing frame. These two steps combined would get me, at best, a 2-stop illumination improvement, so I'd still be looking at ~3 minutes for many negatives.

Sure, I could spend big bucks for a 150mm f/4 APO-Componon HM and get another stop, but this is way overkill as I'm just "imaging" the negative carrier's opening. And I know for $10 I could get a reflector with a light bulb, but my workspace is tight and I'd like, if possible, to be able to use my existing setup.

It would be really cool if there were a cheap lens in the 135-150mm range that covered 4x5 and had an aperture around f/2.8. I'm not talking Xenar here, but cheap, with crummy image quality. It doesn't need an adjustable aperture. As a bonus, it would be light enough that it wouldn't tip over my enlarger (well, I'm exaggerating a bit, but a 150/2.8 will not be a lightweight). Maybe a simple lens from Edmund Scientific? Aberrations shouldn't matter.

Has anyone ever heard of a lens that would fit this bill, or is a reflector in my future?

jb7
13-May-2009, 12:08
I've got a 7" Buhl Projector lens- 2.8
Really cheap on that auction place-

It just about covers 4x5 at infinity,
so shouldn't be a problem closer-

Image quality isn't too bad either-
considering its coverage and speed-

I've also got a 9" and a 11", 3.1, and a 300mm /2.8 Golden Navitar,
although that turned out to be a telephoto,
and didn't cover the format...

Search for Projector / projection lens...

Gem Singer
13-May-2009, 12:13
How about a 300W bare bulb hung from a ceiling light fixture, and forget about using the enlarger?

Jeremy Moore
13-May-2009, 12:16
Now why do you need to even put a lens on the enlarger? Can you not just lower the enlarger as far as you can go while still getting even coverage over a whole plate area with no lens mounted (I would think spot metering the light on a sheet of typing paper would tell you the amount of drift)?

jb7
13-May-2009, 12:18
duh-
missed the bit about contact printing-
only thing that registered was 'enlarger'

Bob Salomon
13-May-2009, 12:21
Why not just put a 50mm 2.8 on the enlarger and raise the head just enough for the light to evenly cover the negative?

Gene McCluney
13-May-2009, 12:34
You don't need, nor should you use (in my opinion) an enlarger as a light source for contact printing on CONTACT paper. A bare bulb suspended above your table will work just fine, and will plug into any enlarging timer you might have. A bare bulb will give you much more light than an enlarger projecting thru an enlarging lens will provide. You can still do dodging and burning with a bare bulb just fine.

If you are making contact prints on ENLARGING paper, then the enlarger is a good light source, as you need much less light.

ic-racer
13-May-2009, 14:32
Realize that many (most?) enlarging lenses have considerable light fall-off at the edges when wide open. So, if you are using an enlarger light source for its 'evenness of illumination' you will be defeating that when the lens is wide open. If you raise-up to use just the center of the projected light, then you times will got up again.

Steve Goldstein
13-May-2009, 15:09
Thanks all for the replies.

A projection lens is cheap enough. I'm a bit concerned that it won't cover 4x5, though, at least if it was designed for a use in a 35mm slide projector. I want to be able to use the 4x5 negative carrier to delineate the lighting area because it will allow in the maximum total light, at least that's my theory. There's no way to know without trying.

It may be possible for me to lower the enlarger head sufficiently, I'll have to try that too. I can't go too low because I need to get relatively even light across the entire wholeplate negative, plus I need to be able to get in for dodging and burning. Again, no way to know without trying.

Yes, I'm trying to do this the hard way, and a bulb in a reflector (or even not in a reflector) would do the job much more simply. The physical constraints of my workspace give me significant motivation to find an enlarger-based solution.

Steve Goldstein
13-May-2009, 15:11
Realize that many (most?) enlarging lenses have considerable light fall-off at the edges when wide open. So, if you are using an enlarger light source for its 'evenness of illumination' you will be defeating that when the lens is wide open. If you raise-up to use just the center of the projected light, then you times will got up again.

An excellent point! But if I can get the primary exposure down to something sensible like 30sec, I wouldn't mind so much spending another 30sec burning the corners. At 11-12 minutes for the base exposure, that's just plain silly.

Chauncey Walden
13-May-2009, 15:18
A 60-watt bulb in a reflector at 3 feet gives me Lodima times from 7(!) to 45 seconds.

Carioca
13-May-2009, 15:29
Thanks all for the replies.

A projection lens is cheap enough. I'm a bit concerned that it won't cover 4x5, though, at least if it was designed for a use in a 35mm slide projector. I want to be able to use the 4x5 negative carrier to delineate the lighting area because it will allow in the maximum total light, at least that's my theory. There's no way to know without trying.

It may be possible for me to lower the enlarger head sufficiently, I'll have to try that too. I can't go too low because I need to get relatively even light across the entire wholeplate negative, plus I need to be able to get in for dodging and burning. Again, no way to know without trying.

Yes, I'm trying to do this the hard way, and a bulb in a reflector (or even not in a reflector) would do the job much more simply. The physical constraints of my workspace give me significant motivation to find an enlarger-based solution.

You're basically looking for a simple concentration of your light source.
Maybe you could try one of those large reading loupes, off focus.

Gene McCluney
13-May-2009, 18:46
Just go to the hardware store and purchase a $4.98 (or less) clamp light with reflector, and clamp that light to your enlarger pointing down. Use your enlarger as a pole to clamp the light to. You will be much more amply rewarded by printing contact paper the way it was designed to be printed. You can use different sized household bulbs to "zero" in your time to a length you like. The lamp will plug into almost any darkroom timer in place of the enlarger.