New Variable Contrast B/W Lamp House

[Bob Mann]

Would really, really like this in a 5x7 or 8x10 head - any thoughts on scaling it up for those formats?

Some day, maybe. This current project is going to keep me busy for some time.

Would two 4x5 units put together make a 5x8 head?

[cardiomac]

Would really, really like this in a 5x7 or 8x10 head - any thoughts on scaling it up for those formats?

Some day, maybe. This current project is going to keep me busy for some time.

Would two 4x5 units put together make a 5x8 head?

No, because of the foam light seal at the bottom. If I were to make a 5x7 universal head, it would be much shallower and thus more efficient with light. Same with an 8x10 box. Some experimentation would be needed to ensure perfectly even lighting across the negative. It's not hard; I just don't have the time.

[Stefaan VB]

I'm looking for replacement of the opal bulbs in my Durst 139 G. No chance this lamp house (or one of the earlier types) would be produced for this enlarger?

[jose angel]

Stefaan, are this bulbs of any "standard" type? (E14, E27 thread). Maybe if you post a pic of the lamp someone could help. I`m using non-original lamps on my Beseler quite successfully.

[Stefaan VB]

Stefaan, are this bulbs of any "standard" type? (E14, E27 thread). Maybe if you post a pic of the lamp someone could help. I`m using non-original lamps on my Beseler quite successfully.

These 200 or 300 Watt (on 220-230 Volt) bulbs have a E27 thread. The diameter is 110 mm (4 1/4"), because I use the enlarger with old glass plate negatives of 13x18 cm (5x7). It has become almost impossible to find this kind of bulbs.

[jose angel]

If the bulb diameter is 110, it is quite big. Philips Photocrescenta bulbs start at, say, 60mm diam., available in 75, 150 and 250watts (220volts).

Have you tried them? My Beseler use a very small, high power bulb, stupidly expensive. I tried a bigger Photocrescenta from an older enlarger and didn`t noticed a difference yet! (Beselers have adjustable condensers).

Also, the original power use to be too high to my taste, for my printing sizes I have to use 4-8X neutral grey filters. I like enlarging times for around 15-20 seconds at f8; it could mean half the recommended power... so I`m currently looking for a 35-50 watt bulb, LED type...

What I want to mean is that maybe you should look for other than the recommended bulb; even the bulb holder/housing can be easily changed, if needed (not because yours is quite common). Just test them for color and even illumination across the frame.

[Stefaan VB]

I have tried some different types of bulbs, the photocrescenta is one of them (I used them in my old Leica 35mm enlarger). The problem is that the diameter of most lamps is not large enough to illuminate the negative egally. The photocrescenta is large enough for 6x6 negatives (in combination with the correct condesors) but it doesn't allow me to use bigger ones. So I keep looking for a good solution - I still have two old but unused spare bulbs, so that keeps me going for another while.

[Richard M. Coda]

I would be very interested in a Beseler 810VXL version of this.