Your power supply is rated at 29.3v at 2.7A. If you do the arithmetic, you get 79.11 watts. The recommended lamp is 30v80w. Underrun slightly, you will be within the capacity of the power supply. The 24v bulb was brilliant, but would have a short life with much bluer light. Your output voltage must be dead on with the lamp spec, or your colour temp will be way off. If the voltage takes a detectable interval to reach spec, the unit requires repair.
I'm going to meter the illumination output between condenser and color head tonight. If similar, maybe it's just the lower wattage of the bulb. I'm not printing color so I don't need stabilized power, just the correct voltage to the lamp. PDH provided another 100w bulb so I'm back to the local lamp shop to see if they have a lamp converter which would work.
I printed before daybreak with a member provided 601M condenser set and glass inserts. I'm very appreciative of the assistance from Apug members. Used the recommended 75w bulb, 645 neg, enlargement factor 5x (6x8 in centered on 8x10 in). Ilford PQ developer, 20c, EMAKS G3, exposure 30s at f8, 80mm clean Schneider optic. The same neg would have printed less than than 20s on a LPL or Beseler B23c. Is this typical and why Durst mentions a 150w bulb.
Pentaxuser, modern diffuser boxes are lined with white styrofoam. Your more recently designed 605 may have styrofoam to reflect light vs the 601s aluminum mix box. I assume white styrofoam is more efficient.
I metered light intensity between my LPL 670 CXL and the Durst M601 condenser. Using the same 80mm lens/f stop, head height and projected illumination diameter on the baseboard the 601 with 75w bulb was 2 1/4 stops dimmer than the LPL 75w bulb. Replacing the Durst 75w bulb with a PH212 150w bulb increases the 601 illumination to match the LPL CXL 75w light intensity. Logically the 601 reflex system is not as light efficient as enlargers with the light source directly above the condensers.
The 601 head temp was noticeably higher with the PH212 but not excessive. The glass negative carrier will keep the negative flat.
My color head issues are not worked out but it appears I need the highest light intensity available with recommended halogen lamps. The Durst compact head bounces light 45 degrees to the baseboard resulting in less illumination.
It turns out I will need to get a 30v 80w halogen lamp as my transformer will not support the 100w lamp.
When I look for the right lamp you run into a bunch of variations. I'm guessing one needs this from elightbulbs.com
80 watt 30 volt MR16 EPK Projector / Stage / Studio Incandescent Light Bulb
80 watt 30 volt MR16 Bi-Pin (GX5.3) Base 3,400K Clear EKP Reflector Projector / Stage / Studio Halogen Incandescent Ushio Light Bulb
Does anyone know the right lamp.
EKP/ENA. These are narrow angle lamps, there are several available with wider angle beams, they will not beam the light through the filter aperture, and you will lose a lot of light. Unfortunately, most of the integrated reflector lamps are 'floods' rather than narrow 'spots'.
Great info. Hope this helps others who run into similar problems. Makes you appreciate a sole condenser enlarger.
I can't print with the color head yet as I do not have the proper halogen bulb; 30v 85w. This is not a common lamp at your local big box store.
I experiemented with the condenser head by replacing the tungsten 75w bulb with a 100w Compact Florescent. Did not work. The light was very dim. It may be easier to place a diffuser under the last condenser. That would avoid having a voltage stabilizer on the counter. One can switch from a condenser to more diffused light from a single head. Very simple. In the past I used two light sources for contrast control with graded paper. I have limited, unvented space so I try to avoid two developing trays.
Durst are not dim enlargers. At least my M600 isn't.
On my old Durst M600 I had to drop down from 150w to a 75w bulb, because the 150w bulb was giving me too short an exposure time. I think it was less than 5 sec with the 150w bulb. And at one time I was considering going down to something less than 75w to give me more time to dodge and burn, but I could not find a 25w enlarger blub.
This was printing 35mm film to about 8x10 or 11x14 with a 50mm lens.
If I printed smaller than 8x10, I used a 75mm lens, to keep the head further from the paper than with a 50mm lens.