CONDENSER COVERAGE

[Deryck]

Hi all,
I have recently married a standard 150 watt "BESELER 45MX" condenser lamphouse, to the negative stage of a rescued "DEVERE 504" enlarger. (the colorhead on the DEVERE was missing).

Both condensors on the BESELER are at the standard fixed distance from each other in the BESELER lamphouse, and the lowest condenser on the BESELER is about 1 centimeter (1/2 inch) above the negative plane on the DEVERE, and is attached directly to the DEVERE negative stage without the use of the normal intervening bellows between condenser housing and negative stage. (Please see the attached jpg file)

Film coverage is Ok, and was easy to check. But would anybody out there know of an empirical method of testing this setup to check whether the condensers are giving the optimum illumination for a 4x5 film format?.

Thanks for your time.

Deryck

 

[Ian Grant]

The condensers need to be only slightly wider than the negative diameter, The critical part is the placement of the bulb above the condensers to give even lighting.

Use a light meter to measure the intensity on the baseboard at the edges/corners and centre.

Ian

 

[Ian C]

Ask someone who owns the Beseler 45M condenser enlarger to measure the distance D from the negative to some easily-accessed feature on the condenser head when the head is adjusted for proper coverage for the 4” x 5” format.

Then you can adjust the position of your Beseler 45M condenser head on the DeVere 504 so that the carrier-to-reference point is the same dimension D.

 

[Wade D]

Your set up should be fine. On my 45MX the bottom condenser is about 1 inch from the negative when set for 4x5. The higher settings (farther from the film) are for correspondingly smaller formats.