Alternate Color Head for 45v-XL

[McSnood]

I have a 45v-XL with a Beseler 45 Computerized Dichroic Head. Has anyone retrofit a "Non Beseler" 4x5 color head to a 45v-XL chassis?

Everything still works, even the MODULE but would like to have better quality for repeatability.

Dave

[Drew Wiley]

There were different models of Beseler electronic-controlled heads. You don't state exactly which one you now have. But yes, any number of other colorheads could easily be retrofitted, even from other brands, provided they aren't clumsily oversized or too heavy. But each needs its own dedicated power supply and controls.

Any high level of repeatability requires some kind of feedback circuitry and monitoring, which inherently adds a bit of electronics complexity, along with any extra idiosyncrasies and maintenance issues which comes with that. But it also helps to standardize on exposure which aren't too short, since bulbs have a brief warmup and well and afterglow phase of different color temperature than the main duration of the exposure. I don't like to use exposures much shorter than 10 sec even with very sophisticated feedbacks systems in place. A few very expensive colorheads use a shutter in the light path to trim off the very initial and final problematic phases of the illumination. It also depends on both the main dichroic filters and the
secondary ones used for the feedback loop all being equally clean and in good condition. Filters can build up grime and haze, or if quite old, spall off some of their dichroic coating. Of course, be very careful cleaning those if necessary.

I wouldn't call Beseler helpful at all regarding some of their previous colorheads. They've changed ownership at times, and tend to abandon or orphan previous products they no longer wish to service. But for a steep price, there are private parties which can generally do so.

[McSnood]

Thank you Drew,
The color head is a Dichro 45 computerized color head with working MODULE and probe. Thank you for your additional comments, I typically expose 30+ sec for reasons you stated. I know this particular color head is not the most stable in the long term and looking for alternative "non Beseler" heads that may be made to fit the 45v-XL chassis. Thanks again for your comments.

[xkaes]

Just curious, are you saying the analyzer lacks repeatability or the color head lacks repeatability -- or both?

The "problem" might be how you are using the analyzer. What tests for repeatability have you done, if any?

[brucetaylor]

There are plenty of other Beseler heads out there besides the one you seem to be referring to (the Beseler/Minolta head is the only one I recall with a remote probe). Given the reliability issues of many of the electronically controlled models the old Dichro DG head is fully manual/mechanical. Alternatively I think the new LED head from Intrepid looks interesting.

[xkaes]

Another option -- if you think the "system", not the head is the problem, is to get a separate color analyzer. For example, I use a Beseler PM2L color analyzer. It's really the same thing as what you have -- just not built-in to the head. I've never had a problem with "repeatability" -- whatever that means. PM2L, and similar, analyzers can be had for under $20 nowadays.

[McSnood]

Thank you for all the comments, the MODULE is the weak link in this system and will look into another analyzer to verify readings. I know at some point this system will no longer work properly and will abandon it and looking for alternate system to mount on the 45v-xl chassis. Thanks Bruce will look into the LED from Intrped.

[shadow images]

You can adapt just about any head to the VXL.