RE: [Leica] Light in the darkroom?

[Henning Wulff <henningw@archiphoto.com>]

At 11:04 PM -0400 7/30/01, Austin Franklin wrote:
>I have fluorescent lamps in my film loading room.  They, absolutely, without
>question, do NOT fog my film.  They also emit NO, and I mean ABSOLUTELY NO
>light within a second after being turned off.  I believe that some
>fluorescent tubes MAY cause a problem...but not all do.
>
>I stood in the outside room with the lights off so my eyes were adjusted to
>the darkness, then I shut the lights off in the room in question (switch is
>on the outside), and opened the door and there was no noticeable light from
>the overheads.  I stared at them for almost a minute...and nada, zip,
>nil...'nutin.
>
>>  -----Original Message-----
>>  From: owner-leica-users@mejac.palo-alto.ca.us
>>  [mailto:owner-leica-users@mejac.palo-alto.ca.us]On Behalf Of r g
>>  Sent: Monday, July 30, 2001 10:34 PM
>>  To: leica-users@mejac.palo-alto.ca.us
>>  Subject: Re: [Leica] Light in the darkroom?
>>
>>
>>  http://www.kodak.com/global/en/service/tib/tib3101.shtml
>>
>>  "Never have fluorescent lamps in the darkroom! Fluorescent lamps remain
>>  glowing after the power is turned off and will cause film fog."
>>
>>  rg

Part of the problem can be that in the presence of EM fields, even 
the type found in households, flourescents can emit or continue to 
emit UV radiation in particular without being themselves switched on. 
If you have no power carrying wires close to your tubes, you should 
be safe, but do you know what wiring is behind your fixtures?

There's no point in being paranoid about this, as in most cases 
flourescents will be fine, as long as you wait a couple of minutes. 
Instead of arguing about theories, why not test your situation? Turn 
off your flourescents, wait a measured amount of time, and hold a 
normally exposed strip of the fastest film you use within a foot of 
the tube, with half of the film shielded. Develop it.

Make sure that other appliances that are likely to have their supply 
wiring running near the flourescents are turned on.

If you get no fogging, and you feel that there is no other power 
carrying wiring, or high frequency wiring in the neighbourhood, use 
the flourescents.

Otherwise, be conservative and use incandescents and (for those of us 
who like them) a Thomas.

- -- 
    *            Henning J. Wulff
   /|\      Wulff Photography & Design
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