Light Bulb Sizes for Condenser Enlargers

[shoot6x7]

My Durst M805, bought used, came with a blown DURA150, the middle bulb above. On the left is a PH212, supposedly a good replacement for the DURA150 !

Aligning the light source is important, so will the PH212's larger size be able to mimic the performance of the smaller DURA150 ?

Thanks,
Ron

 

[Hilo]

I googled for a moment and found this: For LURIOKIT BW condensor: 150W opal lamp (order code DULAMP 150) or - for short periods - 250W lamp (order code DULAMP 250)

About the larger PH212 bulb, the first question is if it will fit. If yes, you just install it. Bring the enlarger to about 40X50cm print height (16X20) and project on a white surface. Turn off all darkroom light and close the lens step by step while you do this. It will make it easier to see if you have even illumination. If you do not see problems, the next step is to make a print . . .

edit:
Sorry, I forgot to say first project without a negative ! This is also the reason for closing the lens, almost all the way . . . you see well uneven illumination then !

 

[Luis-F-S]

The larger size should give better coverage. It's when the bulb diameter is smaller that there usually an issue.

 

[Ronald Moravec]

Distance from bulb to condenser is important.

Always check bulbs and batteries before buying equipment.

 

[bence8810]

Sorry to hijack the thread - you mention distance of the bulb from condenser.
My Lucky 90M-D enlarger has an adjustable bulb height which I've just recognized recently.

What would it do if I lifted - or - dropped it a bit?

Thanks,
Ben

 

[Hilo]

Sorry to hijack the thread - you mention distance of the bulb from condenser.
My Lucky 90M-D enlarger has an adjustable bulb height which I've just recognized recently.

What would it do if I lifted - or - dropped it a bit?

Thanks,
Ben

Most likely it would change the yes/no even illumination. The Leitz Focomat and Valoy II enlargers have the same possibility, to raise or lower the bulb. The right bulb can be very important. When the bulb is longer (or larger) one must often raise it's position.

 

[bence8810]

Most likely it would change the yes/no even illumination. The Leitz Focomat and Valoy II enlargers have the same possibility, to raise or lower the bulb. The right bulb can be very important. When the bulb is longer (or larger) one must often raise it's position.

Thank you!
How does one check if the current position of the bulb is correct?
The rod that moves the bulb can be raised in total by about 10cms so it's quite substantial. I have used it in the position it was set at the time I took delivery of the enlarger and just now noticed it's adjustable.

Ben

 

[shoot6x7]

Regarding the ideal currently available bulbs for the M805, a semi-retired Durst serviceman recommended a PH140 over a PH211/PH212/213 shaped bulb. If in a push, I think the PH21X bulbs can be used but the bulb positioning shaft has to be lowered quite a bit.

 

[Hilo]

Thank you!
How does one check if the current position of the bulb is correct?
The rod that moves the bulb can be raised in total by about 10cms so it's quite substantial. I have used it in the position it was set at the time I took delivery of the enlarger and just now noticed it's adjustable.

Ben

See my first post in this thread !