Durst CLS450, unstable light after 25 seconds

[joachimboegedal]

Hallo,

I have read through many pages about the Durst CLS450 head but seem to not be able to find a solution for my problem so I will try a post.

Long story short, I have a Durst CLS450 which "powers up" after 25 seconds. The light is stable till it hits 25 seconds and the light suddenly becomes brighter.
Is this a feature that I don't know about or is there something wrong with the power supply?

I tested an older Durst CLS450 that I originally swapped out with this "new" one, both are doing the same.
Could this be an issue with the power in the building? It's an older building from 1904 in Germany.

Also I swapped it out because the yellow filter seems to lack yellow when color printing. Couldn't filter out the blue cast. Seem to have the same issue with the new head also. But can be corrected through adding Cyan.

Did someone experience the same issue or have any idea what is going on here?

 

[koraks]

Welcome to Photrio @joachimboegedal !

I tested an older Durst CLS450 that I originally swapped out with this "new" one, both are doing the same.

Did you use the same power supply with both heads?

My first thought would be either the power supply unit, or a corroded bulb socket. The latter is unlikely if a second head performs the same way.

Also I swapped it out because the yellow filter seems to lack yellow when color printing.

The question here is mainly if this is due to the dichroic filters and their adjustment mechanism, or a cause external to the head. You you always have a blue/yellow filtration problem, regardless of what film you're printing from and how that film has been processed? Can you show an example of the uncorrectable color cast?

But can be corrected through adding Cyan.

This suggests it's not a blue cast, but a cyan cast. Cyan casts on color RA4 paper are usually caused by either cross-contamination (blix in the developer; even a tiny bit will be a problem) or use of a color safelight that doesn't turn out to be as safe as anticipated.

Can you tell us a little more about your Ra4 color process workflow? I have a very strong feeling your color cast problem is unrelated to your enlarger.

 

[joachimboegedal]

Welcome to Photrio @joachimboegedal !



Did you use the same power supply with both heads?

My first thought would be either the power supply unit, or a corroded bulb socket. The latter is unlikely if a second head performs the same way.



The question here is mainly if this is due to the dichroic filters and their adjustment mechanism, or a cause external to the head. You you always have a blue/yellow filtration problem, regardless of what film you're printing from and how that film has been processed? Can you show an example of the uncorrectable color cast?


This suggests it's not a blue cast, but a cyan cast. Cyan casts on color RA4 paper are usually caused by either cross-contamination (blix in the developer; even a tiny bit will be a problem) or use of a color safelight that doesn't turn out to be as safe as anticipated.

Can you tell us a little more about your Ra4 color process workflow? I have a very strong feeling your color cast problem is unrelated to your enlarger.

Thank you for answering!
I tested out different power supplies, different timers, switched the bulbs around between heads. And its still happened after the 25 second mark. One thing - the bulbs are both old, will order some fresh ones and see if that could make any difference.
The blue/cyan cast is coming from the CLS450 heads, I run a darkroom here in Stuttgart and have no issues with the other machines (Durst 305M - Durst 605M - De vere 504 converted to LED) I tried both self developed and prof developed c41's both still having this blue/cyan cast sadly with the CLS450s. But I need to test it about a bit more.
For now im more concerned about this power issue, which I can't find any information on, so i'm starting to think its something with the power outlets of the old house.

 

[koraks]

so i'm starting to think its something with the power outlets of the old house.

I find that very hard to believe. I mean, it's easy to believe that the electrical installation in the house isn't magnificent, but it's very hard to believe that this would result in a consistent 25-second delay before the bulb comes on in full power.

It's very puzzling this problem seems to follow you around even if you switch out power supplies as well as heads.

See what some further testing tells you; try to be as systematic as possible and take good notes.

 

[MARTIE]

I definitely think it's a good idea to try new bulbs and also to check the wires and connectors to avoid poor contact. This could be all that it is.