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bizarrius
25-Mar-2017, 07:51
Ok so, i live in a small island and its really hard to find an enlarger for 4x5 negatives. all old labs either threw away their enlargers or they never shot 4x5 in their lives. i look like an outcast here asking for 35mm cn develop, imagine their faces when i ask for a 4x5.

Anyway. i am lucky enough to have a perfect magnifax4 i brought with me when i came back to Cyprus from my studies in Greece. i have dissasembled the whole thing and i know what its needed for it to accept bigger negatives than 6x9 that it already takes. all i have to do is cut here and there and then add new wider bellows. easy. the real problem is, will it focus? will my 75mm lens be enough? should i buy a longer lens? its focusing travel is 18cm from the negative holder (plus a 3cm recessed holder). will i have enough coverage? should i stop what im doing right now? :D i can also set the whole thing to project through my field camera instead. (it will be a mess but still doable).

Anyone did anything like this?

thanks

Graham Patterson
25-Mar-2017, 08:38
Hopefully someone here has tried this particular conversion. My experience comes from coercing my 5x4 enlarger to do 8x10.

Do a back of the envelope calculation: You need a 135mm (up to 150mm) lens at a minimum for 5x4. If you want to start at 5x4 and go up, you need a lens extension of twice the focal length from the film. That's 270 - 300mm, or 11-12 inches. The Magnifax 4 was designed for 6x9 cm, so the current negative stage is a hard constraint of a little over 6cm, say 3"? That width constrains the 'cone' of light visible by the lens at a given extension, so you will not be able to use the full bellows extension for focusing.

My guess, not having access to the equipment, is that you will not be able to mount the negative high enough above the existing negative stage and still have a decent enlarging range without vignetting from the existing negative stage. If you can make that work, you will then need a diffused LED light source, which oddly enough is the easy(-er) part!

Essentially, if you have a 5x4 camera that can be set to do the equivalent range of enlargement, use that as a model and maybe cut paper/card models of the bellows needs and taper and see if you can make it work over a range of enlargements. This does not address the lens axis to column distance which is another constraint on print size.

Personally I wouldn't do irreversible modifications to a decent medium format enlarger.

mdarnton
25-Mar-2017, 08:51
In case it's not clear, what Graham is suggesting is different from what you are thinking, and is the more common way to approach the problem.

That is to leave everything as it is, , no cutting, and rig up an extension box behind the current neg stage to hold the neg up several inches higher. Imagine the lens and current neg hole as forming a cone of light, and the higher you get behind the neg stage the larger the cone becomes. If you compress the bellows more, the cone opens up more quickly. Eventually it's big enough for 4x5. Then you need to find a new lens appropriate to the new distance to the negative, and that lens should have a focal length around 135mm or so in able to cover the negative, so think in terms of making your cone long enough to accommodate a 135mm lens focused at a target of enlargement size.

And then you will need a new light source, too, big enough to cover 4x5. Currently light pads (the light source equivalent of a computer tablet) and LED movie lights are the favored source for light.

Bob Salomon
25-Mar-2017, 09:58
Hopefully someone here has tried this particular conversion. My experience comes from coercing my 5x4 enlarger to do 8x10.

Do a back of the envelope calculation: You need a 135mm (up to 150mm) lens at a minimum for 5x4. If you want to start at 5x4 and go up, you need a lens extension of twice the focal length from the film. That's 270 - 300mm, or 11-12 inches. The Magnifax 4 was designed for 6x9 cm, so the current negative stage is a hard constraint of a little over 6cm, say 3"? That width constrains the 'cone' of light visible by the lens at a given extension, so you will not be able to use the full bellows extension for focusing.

My guess, not having access to the equipment, is that you will not be able to mount the negative high enough above the existing negative stage and still have a decent enlarging range without vignetting from the existing negative stage. If you can make that work, you will then need a diffused LED light source, which oddly enough is the easy(-er) part!

Essentially, if you have a 5x4 camera that can be set to do the equivalent range of enlargement, use that as a model and maybe cut paper/card models of the bellows needs and taper and see if you can make it work over a range of enlargements. This does not address the lens axis to column distance which is another constraint on print size.

Personally I wouldn't do irreversible modifications to a decent medium format enlarger.

Your 75 mm lens won't come close to covering 45. You will need, at the shortest, a lens like the 120 mm WA Rodagon. And this lens is much scarcer, much better, then the more common 135 and 150mm lenses unless you are buying a 150 mm Apo.
And then the condensers on your enlarger will never cover 45. In short, no, this will not work.

Michael Rosenberg
26-Mar-2017, 08:06
You will really have a hard time making this work as others have pointed out. You do need a 135 mm lens, and suitable column length for focusing. The latter can be solved in part by having a drop table, but focusing the lens for various enlargements would still be a difficulty. An alternative is to make a horizontal enlarger - but you would need a good capenter. A work around would be to make digital negatives and do contact printing on silver gelatin paper. I have a monograph describing how to do that on my website.

Mike

jose angel
28-Mar-2017, 04:45
Bizarrius, if you haven`t done it yet, this thread may be worth a read:
http://www.largeformatphotography.info/forum/showthread.php?133804-convert-De-Vere-504-Bench-Enlarger-(4x5)-to-5x7-help-needed&p=1356248#post1356248
Agree with others above; to make a 4x5" enlarger out of a Magnifax seem a not so easy to me. I think you`d be way better taking the most of your enlarger (good lens, good light source, perfect alignment) in the 6x9 format. And not a huge difference from 4x5", BTW.

esearing
1-Apr-2017, 05:04
Take a look at this too. https://www.flickr.com/photos/51921599@N04/7100217243. Then you can work with your existing camera or find a sacrificial one to use.

Greg
1-Apr-2017, 06:11
Take a look at this too. https://www.flickr.com/photos/51921599@N04/7100217243. Then you can work with your existing camera or find a sacrificial one to use.

Linhof also made a "cold light illuminating head" and a "condenser enlarging attachment" for their 4x5 Technika. They also mentioned in their General Catalog a "Agfacolor Head" but I've never see one these .