Saunders 4550 - vibrations from enlarger fan

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Hi,

A question for those of you who own a Saunders 4550 enlarger...

I have a Saunders 4550XL enlarger I bought on consignment at a local photo shop here in Seattle. After a time, a realized why the enlarger was probably put on sale - periodically, enlargements would appear with an "vibrating" effect. Thinking that the problem was the fan, I ordered up a new one from Saunders in Rochester, N.Y..

Yet, still even with the new fan installed, I get exposures/prints that appear to be all shaken.

When I lightly touch the negative platform, I can feel some degree of vibration. I can only suspect that the new fan is not vibration free and is thus giving trouble to my prints.

Is a degree of vibration normal for this enlarger?

Many thanks for your answers.

Robert

-- Robert Ruderman (ruderman@seanet.com), June 17, 2001

Answers

As a step in diagnosing the problem, have you examined the image with a grain magnifier? Check how sharp the detail is and whether you can detect vibration. As a test, you could BRIEFLY disconnect the fan and see whether the resulting print or magnified image is sharper. This should only be done for one exposure because extended operation will cause overheating and possibly a fire hazard. What enlarger lens are you using and at what f-stop?

-- Michael Briggs (michaelbriggs@earthlink.net), June 17, 2001.

Hi Michael,

I do use a grain magnifier when focusing. I can not see any sort of vibration via the magnifier. Are you thinking that the focus is changing on me over time?

Because of the way that the fan assembly is manufactured, it is not trivial to disconnect power from the fan. The fan and the lamp housing are basically in the same piece of hardware.

I am using a Schneider Componon-S wnlarging lens, typically at F22 or F16. Print exposures typically are at 30 seconds or longer. When I am making multiple exposures (for VC printing), the problem is more likely to appear.

Thanks, Robert

-- Robert Ruderman (ruderman@seanet.com), June 18, 2001.


With regard to "feeling some vibration" at the negative stage, I have a Beseler 45MXT w/dichro head and when the fan is on I can also "feel" the hum of the fan when I place my finger against the negative stage. However, I've had nothing but sharp prints (up to 20x24) for 3 years now. Apparently the "sound" (low frequency vibration) of the fan is easily transmitted via the metal parts of the enlarger but is nowhere near energetic enough to cause movement of the enlarger stage or lens stage relative to the baseboard. Usually vibrations large enough to have a visible effect on the print will have an external source, e.g., people walking in the next room, refridgerator just beyond the wall, vibrating central heating ducts, etc. If possible, try to anchor the head to wall studs with some wire and turnbuckles, but not too tight to pull the head out of alignment but enought to act as an effective damper.

-- Steve Baggett (sbaggett@midsouth.rr.com), June 18, 2001.

Robert, I too notice some vibration with the fan, but I accept there is bound to be a small degree of vibration.But I think that one probable cause could be with the negative popping during lengthy exposure times, as the lamp gets HOT! despite the fan. I found that I had a real problem with 6x9 negs (the focus would shift whilst making test prints/strips) and occasionally 5x4, but I just purchased the glass neg carrier and guess what......perfectly flat negs! (The top glass is anti-newton and a blast of canned air and its clean with no dust). Regards Paul

-- paul owen (paulowen_2000@yahoo.com), June 18, 2001.

If you can't see any vibration with a grain magnifier, then you haven't got any vibration.
Incidentally, why are you using such small apertures? The Componon-S gives it's best definition close to maximum aperture. If you need longer exposure times it would be better to fit a lower wattage bulb if that's possible, or to add some neutral density filtration in the light path. Equal quantities of CMY perhaps?

-- Pete Andrews (p.l.andrews@bham.ac.uk), June 18, 2001.


Paul's answer brings up an interesting point. Looking at some of the prints which have a "shaken" exposure, it is odd that, in many (but not all) instances, the parts of the prints closest to the edges of the negative remain "not shaken".

Does this symptom lend itself to the negative popping under the heat of the lamp during exposure(s)?

-- Robert Ruderman (ruderman@seanet.com), June 18, 2001.


If the enlarger head nears the ceiling of your darkroom, heat from the fan could cause the negative to pop in the carrier. You might try a glass carrier or tape down the neg and try to make prints. Bob

-- Bob Moulton (bobmargaretm@home.com), June 18, 2001.

I may have missed it in the above threads, but I don't think anyone has mentioned an unstable enlarger. I have a Saunders enlarger and have not had the problem you describe from the fan. I do use the glass negative carrier when I am serious about a print, especially if it takes a long exposure. My darkroom is located above my garage. If the garage door opens during an exposure I will get some vibration blurring. I can blurr the image if I jump up and down, even with the enlarger secured to the wall. If I put too much bass on the CD player I can feel the vibration on the paper easel. I haven't tested to see if this manifests itself into a blurred print. I simply turn the volume down. I'm guessing your negative is moving from the heat or your enlarger is not secured as well as you think. Try to remain still while you are printing.

-- Paul Mongillo (pmongillo@thurston.com), June 22, 2001.

Many years ago Shutterbug compared an older Saunders 45 enlarger to an upgraded model. To test fan vibration they attached (to the fan housing or negative stage- I'm not sure which) a long piece of very thin piano wire with a piece of cork on the end. I seem to recall the wire was about 18 inches long. Cork movement would reveal fan vibration. You may want to try this very cheap test to put your mind at ease.

-- Bill Eadie (wae5@pacbell. net), June 23, 2001.

Hi Robert

Hope you have saved that problem meanwile. I just remember on a photographer he had a similar problem but only from time to time. His labor was in the middle of a city near a railroadstation and a big street. He gets some vibs from trains and also from heavy trucks on the street. He changed the location outside of the city.

-- Armin Seeholzer (armin.seeholzer@smile.ch), October 26, 2001.



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