I just bought an old 4x5 enlarger that has both condenser and diffusion sources. This thing is a real tank, circa 1960. The "cold light" source seems extremely dim, and vignettes at the corners regardless of magnification. (???)

I am clueless as to what bulb to use for the condenser source, as there was none. Any recommendations of what size to try first? The bulb socket is approx 12" above the carrier.

Any suggestions/advice appreciated.

-- Matt O. (mojo@moscow.com), December 29, 2000

Answers

It might help if you can tell us what model the enlarger is. Most enlarger light bulbs look just like household bulbs, but there ARE specially made for enlargers. I don't remember exactly, but I think my Omega D3 takes a "211" or some such number sequence - the bulb model was printed on the side of the lamp housing. You have to get it from a (large) photo store. (And I'm running on my "spare" now, so I have to make the 140 mile round-trip trek to Orlando for another.)

-- John H. Henderson (jhende03@harris.com), January 02, 2001.

The unit you have sounds like it's about the same size as an Omega Dx. If your condenser lenses are about 6.5-7" in dia and about 3" thick the design parameters will be about the same.

The bulbs for a 4x5 omega condenser head are the 211/212 at 75 and 150 Watts respectively. There is a smaller one that my D3 came with; I think it was a 247 but it was definitely the wrong size and led to incorrect illumination. These bulbs are available at most photo- darkroom places for under $5.

There is no rocket science here. The 211 is about the same size as a 60 W bulb but is not made translucent the same way. You could try a standard bulb but there will likely be some illumination problems (you may get artifacts from the lettering and it will be uneven overall) but it will at least do something.

Good luck & cheers,

Duane

-- Duane K (dkucheran@creo.com), January 02, 2001.

I'm not really certain what brand it is; the condenser housing says "Skyview" - there are no other markings at all. The diffusion source is a round "cold=light" and is labeled DeJur. The neg carrier is round (7"dia) and machined aluminum. It is totally manual (i.e. lift and tighten!) The condenser lenses are approx. 7.25" dia and held at the appropriate distances with an aluminum spacer ring.

-- Matt O. (mojo@moscow.com), January 03, 2001.