Vibrations on a D5XL with Dichroic head

[Dave Tolcher]

I have just bought Super Chromega D5Xl with a dichroic head and have not got it installed and ready to go. I was surpised at the amount of backgound vibration f rom the large fan that cools the lamp. Is this normal - can I disconnect the fan ? I will try some printing this afternoon to see whether it is a problem but I can feel vibration on the baseboard and on the enlarger head.

Any experiences or thoughts ?

Thanks

Dave

[Steve Baggett]

When I first set up my new Beseler 45S Dichro color head, I could place my hand on the negative stage or lens stage and "feel" the hum/vibration of the fan. I was disturbed at first but tests showed no effect on the image. I came to the conclusion that this was "sound" transmitting throughout the head/neg stage/lens stage as a single mass unit and could not be causing image blur since the whole assembly was not moving relative to the baseboard. The type of vibration that affects print quality is where the above "mass unit" vibrates as a pendulum on the chassis relative to the baseboard. This can be fixed by securing the upper chassis to the wall (with wire and a couple of small turnbuckles) or by using (in the case of Beseler) a vendor supplied upper chassis support bracket mounted to the wall. I would NOT recommend disconnecting the fan as the bulb wattage probably requires cooling in your D5XL (anything above 100 watts probably requires it.)

[Dave Tolcher]

Thanks Steve, your right in that the 'hum' does not affect image quality. I have just emerged from a first session in the darkroom with the beast and am very impressed with the quality it can deliver - certainly every bit as good - if not better than my MF Fujimoto. I had some new 6X7 negs which printed up well using the 5X4 glass carrier and printed my first 5X4 negative. Its wonderful seeing the print from the LF negative - its been a long time coming and quite a tortuous path. Incidentally I havent yet purchased a 135 or 150 lens but used the 100 Componon S that I use for MF and it didnt seem to have any problems. Would I see any improvement with a longer lens ?

Thanks

Dave

[Michael Feldman]

If you stop down far enough (f/22+ ?) the 100mm might just barely cover the negative OK. But you are likely to get some light fall off at the corners at f//11, which is probably the sharpest aperture for the f/5.6 enlarging lens.

[paul owen]

David, Congratulations !! Now find yourself a good used Schneider/Rodenstock/Nikon 150mm and you'll not suffer with any light fall-off on your prints!! Regards Paul