I was fixing a Hansa enlarger over the weekend that I picked up in an as is state as part of a way cheap lot. There was poor light output with it.
The lamp house cover was taken off to have a look under the hood. It was apparent that the bulb, a 75W unit like in Omega's I have seen, was not clipped into its mounting position. I made up a new clip with some copper wire, and now the light bulb sits so 100% of its beam goes into the optical path, as oppused to about 30%.
It was still dim. Pulled the mixing chamber to see what the diffusing media looked like. All was still clean and white, but a mirror box used to turn light from the lamp after the filters into the box had only ever been friction fitted, and it had slipped low. Pull tape on the back of the enlarger, and there were two screw holes that lined up with tapped holees in the mirror box assembly. Two salvagesd small screws later, and the mirror assembly was mechanically held in proper alignment.
While the hood was off, I looked at the filters. All looked good and clean, but the Y one was stuck into the optical path about 8% even with its dial at zero when the filter lift lever was slid from white to colour. Minor disassebly ensued, and a linkage was carefully bent to allow the yellow to fully clear with its dial at zero. As a part of this investigation, I found that the filters fully engaged in the light path by the time the dial was turned to 120, despite being able to turn all the way to 170. I guess the cam designer was not fully conversant with the filter lever designer to match their system values properly some 30 or more years ago when this thing was being designed.
After re-assembly things were looking good.
To calibrate the thing a bit better for printing with MG B&W paper, since it now is know to have wierd filter settings, I sat its light path under my Lici 3000 colorstar analyser.
On white setting I would stick an Ilford MG filter in the neg carrier, and then fiddle with the analyser programming on an idle channel to null the display. I would then pull the llford MG filter, and use Y and M dials to match the colur the MG fiter made. I did this for filters from 00 to 5, and now have a table to start with to do a real calibration tonight printing step wedges onto MGIV to see how many steps I actually get for each of these settings.
I really bought the lot this enlarger was in to get the old paper boxes, which included the papers that I started out printing on over 25 years ago.
This enlarger once tuned in, will form the nucleus of a collection of surplus to me bits that I can set up in the laundry room on top of the washer and dryer to teach interested people how to do their first b&w printing. I have found that I have so much stuff crammed into my normal darkroom that it scares them off that they could ever pick up this craft if I introduce them to it in there.
By doing it bare bones, it is simplified, and if a person expresses an interest, I make a deal to sell/mostly give them all to get started from an old camera to the enlarger, chemisrty, film, paper and bottles, trays etc. to get them started. I have done this once now, and want to have a rig to be able to offer this agian.
The other cool thing with this particular enlarger is that this enlarger bulb is 12V, so it is feasible to run it in a set up on the road in a remote location powered from an automotive source. Looks like it is time to start looking for compatible 12V bulbs for a safe light.
my real name, imagine that.
Hi Mike. I think you can still buy 12v incandescent bulbs in standard base in wattages from 25 to 100. Maybe an RV dealer would stock them. You could use one in a standard Kodak safelight.
"I'm still developing"
Just to let you know, I took the enlarger back and the chap at the shop stripped it down, put it back together, and pronounced that everything was A-ok with it. Far from convinced, I took it home and put it threw its paces last night.
The brightness seems to have improved by a fractional amount, to the extent that you can just about make out what your looking at when there’s a colour 35mm neg in it. It was still extremely dark however, and there was only just enough light to pick out the grain on a four year old Fuji 400 consumer neg. I stuck to B&W printing last night however, as this is something which I have a fair bit of experience with.
There was far less light coming through the head than with my previous enlarger – the Durst 605 condenser – and this had a substantial effect on printing, to the extent that a 10x8 print which would previously have taken 10-20 seconds under the lamp at f8 is now taking 2 and a half minutes.
Is this normal for a diffuser head?
I’m going to try colour printing tonight using Kodak RA developer and SE in trays at 20 and will report back.
I have a Durst CE1000 with a CLS450 head and power supply with a 250 watt bulb installed. With the 6x6 mixer box installed, my exposure for Supra Endura on an 11x14 print is 6-8 seconds at f11 with a Componon 50 f4 lens which dates from 1963. When I use a 90 watt bulb, I open up the aperture about one and a half stops.
It almost sounds like the filters are all fully in the light path all the time. Does the light change colour when you adjust the filters one at a time?
With all three at max, you have a pretty dark image, whan all are set to zero it should be very bright.
There is still something seriously amiss here. We have the same enlarger with same dichroic head and yet with a 10x8 B&W print my times are under 20 secs at f8 and this is with a 75W bulb and not the 100W that Durst recommends.
Originally Posted by Roger2000
Have you tried what Bob suggests? His test and mine are much of a muchness. Set the Y and M filters to any figure say 50and 50 units then swing them out of the way with the lever on the left or at the back if yours is a slightly older Durst 605 and any colour on the boards should instantly disappear and be replaced by bright white light. Then dial in Y and M as I suggested to check on the progressive change and finally do all three filters by the same amount together say 20 units at a time to see if it progressively darkens but with a neutral grey. All three filters together should give a grey look
That way you can eliminate any problems with the filters sticking.
I have never had a condenser head so can't compare but both B&W and Colour negs are very bright at f2.8. I use this for focusing but f4 is nearly as bright. It is true that at the aperture and with dual filtration for say grade 3 -3.5 correct for an exposure of say 10-15 secs the neg does then look gloomy but that doesn't matter as you have focused. What counts is the print.
However ignoring the darkness aspect of the projection your exposure times are still a complete mystery to me.
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Thanks for all your help chaps.
I had a bash at colour enlarging last night, and found that a 6x4 print from a well exposed 35mm neg took 35 seconds at f8. Obviously when printing at 6x4 the enlarger head was quite close to the baseboard which helped with the focussing and composition. Does this exposure time seem a little long?
I tried the experiment as suggested and found that the in / out arm on the left hand side DID move the filters in and out of the light source. However, when set to ‘out’ and with a fully opened aperture (f4 on this 50mm Minolta enlarging lens) the light coming out was far from bright. Would you suggest buying a lens that can go to f2.8 for compositional purposes?
In addition, I wondered whether there might be a more suitable focusing tool than the smaller of the two Paterson focus finders for use with colour? It’s fantastic with B&W but doesn’t work a jot with colour.
Although I’m very frustrated that the head still seems to be defective, I was very pleased with the quality of the 6x4 prints mentioned above. RA4 prints seem to have a very attractive softness and subtlety to them which is most agreeable.
Is there a mixing box??
If so make sure it is intact.
Originally Posted by Roger2000
35 secs at f8 is way more than I get. As I said I even had to reduce the wattage to 75W because my Paterson colour analyser had a min exposure of about 4 secs and I couldn't null the exposure dial so needed less than 4 secs.
Unless there is something wrong with the aperture movement on your f4, don't bother to buy a f2.8. f2.8 isn't going to improve the light dramatically. Have you checked that the lens' aperture setting is operating properly. When you remove it from the enlarger and hold it up to the light you should see the aperture open and close as you move the aperture setting.
When the seller inspected it on its return and pronounced it OK, did you insist on seeing it in operation? That way the seller's OK and your not OK might be the same thing but 35 secs at f8 for a 6x4 print strongly suggests that the seller's OK is not OK.
Can you find anyone nearby from a camera club who still has some knowledge of enlargers? Unless you can get a knowledgeable second opinion I fear that we never get to the bottom of this collectively. 5 mins in your darkroom with another user might solve this but short of that I am beginning to despair of getting to the bottom of this.
Your enlarger or some part of it is, no doubt, defective, the possibilities ranging from the bulb (wrong voltage, wrong wattage, wrong type) to lens (malfunctioning aperture) -- and the entire lightpath between them. Your light seems at least about three stops too dim. It's quite much. Don't try to get a brighter lens, instead find help to fix the actual problem. It's probably something obvious for someone familiar with enlargers. They are not so complicated.
There are many things mentioned but has anyone mentioned the bulb voltage yet? Check it. If the bulb is for double voltage than the enlarger, that would explain the problem. Halving the voltage may be about two stop loss in light output or even more. And it's always possible that the enlarger gives wrong voltage, different than specified. Measure it if you have access to a volt meter. Or maybe the enlarger has 220V/110V switch and it's at the wrong position. It's easy to check - open the bulb compartment and switch the light on - it should be white and so bright that you almost feel pain in your eyes . If it's a little orangish and lame like the common house bulbs, it's not working at the specified voltage.
Last edited by hrst; 12-09-2009 at 03:12 PM. Click to view previous post history.
Reason: About electricity
If I recall correctly, the Durst M600 series enlargers use a mirror or mirrors to create a light path.
If my recollection is correct, I would check that the mirror(s) are there, that they are in the correct position, and that they are undamaged.