PDA

View Full Version : Rejuvenating old enlarger - Durst 138s Laborator



vizion
25-May-2010, 06:46
Hi

I have a really sturdy old floor standing enlarger. It is a Durst 138s Laborator with all the condensers plus a cold cathode system.
The standard light source is dependent upon old fashioned Opal bulbs 200 W, 150W & 100 W.

I want to change that light source and use something a bit more economical to run, less vulnerable to minor supply fluctuations and most importantly somewhat cooler! It is OK in the winter but in the summmer phew!!

The beauty with this beast is that the head can be turned for wall projection, it has a great range of movements and is as steady as a rock with long exposures.

I want to change my 150, 130 and 105mm enlarging lenses and could do with some recommendations for lenses that will not have too serious an impact on my bank balance.

Most of my work is in B&W so this brute has a real value. HOWEVER I do do some color work. Whilst I have a good collection of kodak color printing filters I have been wondering if it might be possible to pillage the guts of my LPL 6700 colour enlarger head and shoe horn the color controls into the laborator head. It would only be worth the effort if the result would handle 4x5. The LPL guts are pretty damn compact and the Laborator head is quite capacious. However I have no idea whether my notion has any practical viability or what the design limits are for the LPL guts. Would it stand up to the requirements for 4x5 or even 5x7? The idea of combining the convenience of modern design with the massive machinery of a past generation has some appeal to this maverick!

Contributions and insults welcome
David

ic-racer
25-May-2010, 07:10
The hottest running head will be the CLS301 or CLS1000. The condenser head you have will run cooler than that as it uses less power and is more efficient. The cold cathode you already have should run around 37-45C when warmed up and would be the coolest.

If you mains power supply is not constant you can seek a large power stabilization unit. Realizing that it would be unusual for the supply voltage to have so much fluctuation as to affect B&W printing. This topic has been discussed before and the last person on this forum to acquire the appropriate stabilization unit determined the contacts on his timer relay were faulty.

If you are on a budget, I'd seek the silver barrel Durst/Componon lenses. Because they are silver they sell for much less, however, the optics are still excellent. These lenses frequently come in the appropriate mounting cones for your enlarger. If you get a lens without the mounting cone, it can be expensive to adapt it.

I got all the lenses pictured for an average of $30-35 each. They all needed to be cleaned up, but for around $50-100 you can probably get some clean ones. (80mm Componon, 150mm Componon, 210mm Componon).

If you are going to print 5x7, I'd get the Durst/Componon 210mm. I have seen a number of these on e-bay with the appropriate mount for your enlarger in the sub-$100 range. I got a beat up one for $20.

In terms of the LPL guts, don't destroy your working 5x7 condenser head!!

Better to construct an adapter plate for the LPL. If the LPL is busted and you want a cheap 4x5 dichroic head, look for a used Chromega D head, I suspect you could adapt that easily because the bottom of it is flat. Realizing that the Chromega head runs on a 200W bulb and and needs a fan to control the heat. So, your existing 5x7 head will be cooler if you use the 100w or 150w bulbs.