Modifying 6x6 colour head to print 4x5.

[Chris C]

Hey guys.

I'm a little bit stuck with this. I have a Homrich & Sohn 4x5 enlarger which I've been using for a few years now for b&w prints and found it great. The time's come for me to start wanting to do my own colour printing too as I'm a little sick with expensive prints coming back from the lab not like I imagined they'd be, which begins my problem.

When I bought this enlarger it came with this Agfa head which also has a big wooden adapter (almost a mixing chamber) to allow it to be used on the enlarger to print colour medium format negatives. This is all well and good, but I want to print 4x5 colour negs!

My question to you is, is this colour head suitable to modify? I had considered just extending out the white 'cone' from the bottom, which currently stops at just over 6x6 with diffused glass. Would this run me into light fall off problems or any other unforeseen issues?

Starting anew with a colour enlarger has of course crossed my mind, but they're few and very far between here in NZ. Since I bought this enlarger, I've only seen 3-4 others pop up for sale, and I think only one of them was already set up for colour work, and that's in 4+ years. Shipping from anywhere would most likely be prohibitively expensive too, so I'd quite like to use what I've got if at all possible. Am I barking up a tree I should just be lifting a leg against, of is this something that would work?

Hopefully these pictures should give clues to the validity of this attempt.





Thanks for any insight you can provide.

[Greg Lockrey]

If you remove those for screws on the outside edge will that plate come off. If so you might be able to get by if you put a diffuser screen in between the light source and opening. Otherwise depending on the diameter of that mixing chamber I would consider getting a Beseler 4x5 head to fit on top of the enlarger. It kind of looks like it might fit from where I'm sitting.

[CatSplat]

Chris, would you mind measuring the diameter of the round white bit that goes into the enlarger? While modifying the 6x6 to cover 4X5 looks to be a bit of a stretch, Greg's suggestion of using a Beseler head may be just the ticket, if it would fit. The pictures of the unit that you posted on APUG make it look like it might work.

[ic-racer]

Personally I wouldn't bugger up that head trying to modify it. Many 4x5 enlargers have a tapered diffuser (thicker in the center) under the 4x5 light box. Getting even illumination is not going to be easy with that head.

If you look around I suspect you can find a 4x5 dichroic head for cheap somewhere.