That sure sounds like a filter stuck or not moving. What I've noticed when the problem is a socket or bulb is more of an inconsistency from one test to the next, i.e. the color is unstable even when the filter wheels aren't moved. Test that by making a test, don't move anything, then do another test. If you think your timer is off use a different timer - but that only should affect density, not color balance. To test your process control you'd need the test strips manufactured for that purpose.
I'll go back over the functions of the filters, but I don't really know what I'm looking for past the filters moving when I turn the dials. Maybe the lamp isn't seated right, the socket looks very clean and almost new to me. This enlarger saw very little use before I got it 2 years ago- gotta love second had dentist's toys!
You should first just look at the shifting color of light falling on a white card on the easel as you move each separate filter between extreme settings. Then if something seems fishy, you should open the colorhead an inspect each filter element visually. Once in awhile the coating on a filter will wear out and peel, or perhaps, during moving,
some little piece of matter got stuck to one element or an element got broken. Unlikely, but not hard to detect.
I am getting the same color balance no matter what variable. It has to be something with the enlarger! I'll start quadruple checking the lamp,socket, and filters tonight. No idea how to go about checking to see if the head is getting the proper voltage..Originally Posted by Larry Gebhardt
If the color balance is constant then the only variable that would appear to apply would be the filtration. So, follow Drew's suggestion and see if you can tell a perceptible difference in the color of the light as you dial your M or Y wheel.
Oh, I get a difference when making filter adjustments, but even at a setting like Y:5 M:10 it's still WAY to blue/cyan. I've checked the filters again, and they seem to rack back and forth the appropriate amount... This is getting annoying
I assume that you have the timer in line ahead of the power supply. The thing that I would check first is the incoming voltage to the time and the outgoing voltage from the timer. The next thing would be to check the incoming voltage to the power supply and then the output voltage from the power supply.
Since you mentioned this cropped up after you moved, I would suspect a difference in voltage between the two locations. A variance in voltage would cause a difference in color from the lamp. Power supplies are proportional devices the work on a ratio between the primary and secondary winding. Therefore if you have a lower or higher input, you will have a corresponding lower or higher output voltage. That could account for your difficulty.
I have seen municipal voltages vary by more than ten percent from one location to another in the same municipality.
An inexpensive VOM can be purchased from a variety of places. Radio Shack is one such source.
If there are interconnecting cables, make sure their connectors are fully seated. It's possible that a pin may have been damaged or broken.
- Leigh
Most modern enlarger power supplies have built-in voltage regulation. I'm quite sure that would be true of the Durst, which is a professional machine.
It's possible that the feature has been turned off. Some supplies have the option of disabling regulation and relying on an external regulator to fulfill that function. In your case regulation should be enabled.
- Leigh
Then I would dial in a drastic C value (assuming you're working with negs) and try to get the pack into a place where you have some filter adjustment range. Then leave C constant and color correct with M and Y.
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