From: Sandy King (sanking@clemson.edu)
Date: 07/10/02-12:08:24 PM Z
Just a brief addition to the previous message as regards self
ballasted mercury vapor lamps. These lights can be used without
ballast in incandescent fixtures rated for the wattage. However, most
of the high wattage lamps of this type appear to have a phosphor
coating which shields some of the UV light. A brief search on the web
found a couple of 150 watt units that may be of interest to some.
http://homeharvest.com/spotgrowlightbulbs.htm
http://www.zoomed.com/html/powersun_uv.html
Possibly bulbs of this type are available in higher wattage but I
have not so far found a source. As is I suspect they will perform
much like the old sunlamps one used to be able to buy.
Sandy King
>Bob,
>
>The 175 watt mercury vapor street lamps are inexpensive but they are
>far from what I would call a powerful light source. At a distance of
>18-20" from the printing frame I found exposure times to be be
>unbearably long when using just one of these lamps.
>
>A much better source in my opinion would be a 400 or 1000 watt metal
>halide or mercury vapor lamp, in proper housing plus ballast. Also,
>self-ballasted mercury vapor lamps of in 250, 450 and 750 watts are
>also available.
>
>In considering the use of a metal halide or mercury vapor lamp of
>any size one should bear in mind that the most important
>consideration after wattage is whether the lamp is coated or clear.
>Coating, which is generally done to improve the visual qualities of
>the light, serves as a filter to UV light and is quite undesirable
>for our needs.
>
>Sandy
>
>
>
>
>>Philippe,
>>
>> I don't know if you can buy one of these in Belgium, but over here
>>its possible to buy a 150 watt mercury vapor street lamp complete
>>with clear glass bulb for about $35 (35 euro or 175 FF). At a
>>distance of about a half a meter they make a fair approximation of
>>a point source and they have a long lifetime.
>>
>>Bob Schramm
>>
>>>From: Monnoyer Philippe <monnoyer@imec.be>
>>>Reply-To: alt-photo-process-l@sask.usask.ca
>>>To: alt-photo-process-l@sask.usask.ca
>>>Subject: Powerfull UV point source
>>>Date: Tue, 09 Jul 2002 10:08:26 +0200
>>>
>>>Hello everybody,
>>>
>>>I might want to switch from UV tubes to a powerfull point source in UV.
>>>What can I find for such a source ? Is it reasonable price ?
>>>
>>>See you all in APIS ?
>>>
>>>Philippe
>>>Belgium
>>
>>
>>Check out my web page at:
>>
>> http://www.SchrammStudio.com
>>
>>also look at:
>>
>> http://www.wlsc.wvnet.edu/www/pubrel/photo.html
>>
>>_________________________________________________________________
>>MSN Photos is the easiest way to share and print your photos:
>>http://photos.msn.com/support/worldwide.aspx
>
>
>--
--
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