Durst 138s - Latico condensors

[Marco Buonocore]

Hello all,

So I'm going about getting a Durst 138 enlarger into working order. Most of the bits and pieces are there, which is great, and other than being a bit dusty it looks fine.

I've got a bunch of the latico condensors, and have a question: What is the difference between the 240T and a 240R condensors? How come the 85 is not followed by either T or R? Something to do with the coating?

I mainly print 6x6 negs - am I correct in thinking that the 200 goes on top and the 130 on the bottom? And how important is the correct wattage bulb?

Last question (I promise!): what is the purpose of being able to move the bulb side-to-side and back-and-forth on the apparatus inside the head? Is it to avoid hotspots? Is the best bet to center it and leave it at that?

I'm looking forward to making some bigger prints, that's for sure!


Thanks for your help,

 

[RobC]

On the L1200 the T condensors have special coatings to improve optical quality. They are very expensive. I don't know about R. If there is no letter, then I guess there is no coating. I think that T coated were used on the point source L1200 for enlarging electron microscope images where the finest detail was required. i.e. best quality.

The lamp is moveable so that it can be centred over the condensers so that you get even illumination.

 

[Ole]

The T's are coated for use with point light sources, the R, H and "nameless" are not.

How the condensors should best be placed depends on your lens - the manual specifies different combinations for Rodagon, -componon and Componar lenses of the same focal length. If you have several condensors it pays to experiment a bit.

 

[lee]

on the lamp housing of my 138 there is a chart that shows the condenser placement. I have always followed that convention.

lee\c

 

[Ole]

That's on my condensor head too - it's the "Componon" list. The "Rodagon" list is slightly different, and it really does make a difference.

 

[Marco Buonocore]

Thanks all! So the 'T' condensors are coated. Great! Now if only I could dig up a point light source....

I followed the chart, and I've got componon lenses, so I suppose all is well. What would one do with a Nikon lens?

And what on earth is the foot pump for?

Again, cheers for the help.

 

[JLP]

The foot pump is for raising and lowering the base plate. When you push the Petal down you can either raise or lower the board after releasing the large button/screw bellow the base board.

jan

 

[Don Dudenbostel]

The wattage isn't as critical as the size and finish of the bulb. The original bulb for that head is long discontinued and if you can find one it will run in the $75-100 range. I did some research and found a good alternative to be a PH/303 which runs around $15 form topbulb.com. I purchased a couple as a spare and so far have not had to use one. They work just great but are quite bright. Actually they are too bright for my printing so I use a variac to dim it. I run it at 80 volts and print at the aperture and time I like. You could also rig a dimmer for a household light to do the same thing.

Fantastic enlarger. The best IMO. I wouldn't part with mine and have used one for nearly 40 years.

Glennview was a good source for parts as is Jensen Optical. They were a good source for the optical coated glass for the carrier at a ??? reasonable price compared to Jensen.

 

[frotog]

That's on my condensor head too - it's the "Componon" list. The "Rodagon" list is slightly different, and it really does make a difference.

I've never noticed any significant differences between componons and rodagons of similar focal lengths when using the recommended condenser pairs. Would you mind posting the rodagon list?

 

[Philippe-Georges]

Dear Marco,

I have the whole manual in pdf, the Rodagon table is in it, but it is 3,5 Mb.
If you want it, I can mail it to you.

Philippe

 

[edtbjon]

Hello Philippe, I would be very happy if you mailed the pdf manual to me too. (I have had my 138 for 20 years without a manual, but I recon that there is always something new to learn.)

If so, drop me a pm so that I can come back with my email address to you.
//Björn

 

[Marco Buonocore]

I've spent the last few days printing with the 138 - what a joy! I've been using a Durst M605 for the past couple of years, and enjoy it for what it is, but the difference between the two is rather hysterical. It seems to be an almost perfect machine. I just need to get some glass for the carrier.

Thanks for the tips on the bulb source - I will have to make an order. And Phillipe, I would like a copy of the manual. There's one up on Durstprousa's web site, but not in pdf. I will pm you with my email address. Many thanks!

Back to printing!