(Moderator's note: Here are a group of responses to the aviary lighting
thread which I decided to send out as a single posting rather than as
individual ones. There have been a lot of replies and I'd like to
encourage active discourse. Thanks for your patience and participation)
From: "Aart Kooijman" <a.c.kooijman@med.rug.nl>
Organization: faculty of medical sciences (RuG)
To: Color and Vision Network <cvnet@lawton.ewind.com>
Subject: Re: CVNet - followup on aviary lighting thread
Dear colleagues
What I missed in the suggestions to adapt the lighting in the aviary
is the application of high frequency fluorescent tubes.
Classical fluorescent tubes flicker with a frequency of twice the
mains, but modern tubes are controlled electronically
at a higher frequency between 28 and 42 kHz. I assume that it is
unlikely that such high frequencies are seen by the birds.
These HF tubes and electronics are available in Europe in the regular
lighting stores.
Best wishes
Aart Kooijman
From: Frank Schieber <schieber@usd.edu>
To: "'Color and Vision Network'" <cvnet@lawton.ewind.com>
Subject: RE: CVNet - followup on aviary lighting thread
In fact, modern "dimmable" fluorescent lamps have sophisticated ballasts
that run in the 20-40 KHz range rather than at line frequencies.
(essentially eliminating "biological" flicker).
Frank Schieber
University of South Dakota
-----Original Message-----
From: Color and Vision Network
To: CVNetList@lawton.ewind.com
Subject: CVNet - followup on aviary lighting thread
From: Michelle.Waddle@newcastle.ac.uk
To: Color and Vision Network <cvnet@lawton.ewind.com>
Subject: Re: lighting for an indoor aviary
Here's a further responce to the flicker problem with fluorescent lighting.
Dr. Endler,
I was facinated to read about the effects that flicker from fluorescent
lighting can have on animals. Just as a side note in case it may become
important to your investigations later, the flicker rate is actually 100 Hz
in the UK and 120 Hz in the US. A pulse of light is emmitted for each surge
of current through the lamp, whether positive or negative.
Dr. Endler and Dr. Waddle,
There may be an alternate way to mitigate the flicker which might be helpful
if there are any cases where the spectrum of fluorescent lamps are ideal. A
fluorescent light fixture could be wired with three-phase power in such a
way that three bulbs flicker out of phase with each other. The total
emitted light would then be flicker free (if there is an equal number of
bulbs on each phase).
Regards,
Dan Hulsey
Cheers
Michelle
From: Tom Troscianko <Tom.Troscianko@bristol.ac.uk>
To: Color and Vision Network <cvnet@lawton.ewind.com>
Subject: Re: CVNet - followup on aviary lighting thread
I understand you can also buy a (cheap) piece of circuitry which makes
the flicker rate of the fluorescent tubes rise to over 100 kHz, ie
faster than any biological system can respond to... Arnold Wilkins has
used such devices and probably knows how to get them. I can forward any
queries to him.
Tom Troscianko
----------------------
Dr Tom Troscianko
Department of Experimental Psychology
University of Bristol
8 Woodland Rd
Bristol BS8 1TN
UK
Phone 0117 928 8565
Mobile 0774 7000 764
Fax 0117 928 8588
This archive was generated by hypermail 2b29 : Tue May 30 2000 - 10:12:05 PDT