NetNews Usenet Archive 1992 #27/NN_1992_27.iso/spool/sci/electron/19160

Internet Message Format | 1992-11-18 | 1.7 KB

Xref: sparky sci.electronics:19160 rec.photo:20084
Newsgroups: sci.electronics,rec.photo
Path: sparky!uunet!krfiny!jeffj
From: [e-mail] (J. Jonas)
Subject: Re: Lamp intensity vs. lifetime
Message-ID: <[e-mail]>
Summary: different spectrum
Organization: Jeff's house of computer pieces
References: <[e-mail]> <[e-mail]> <[e-mail]>
Date: Wed, 18 Nov 1992 19:21:47 GMT
Lines: 30

>>In article <[e-mail]> [e-mail]
    (Markus Wandel) writes:
>>What about photographic floodlights?  These things have expected lifetimes
>>of just 2-8 hours.  I thought if I ever use the lamps and bulbs that I have

In article <[e-mail]> [e-mail]
    (Phil Ngai) writes:
>Why would you want to use those when you can now get 1.5 kilowatt
>halogen floodlights?

I'd guess that the photographic floodlights have a more balanced
emission spectrum.  The hotter you burn the filament, the more
white light you get (black box radiation and all that jazz).
Photographers are quite fussy about lighting
since they want the true color of the subject getting to the film.
Unfortunately, there's an inverse ration of bulblife and temperature.

Stores love using halogen lamps in the window displays not only
because halogen lamps are small and trendy enough not to hide, but
the whiter, more intense, focused light makes the merchandise more
attractive and doesn't alter the color.  Regular lamps are reddish,
fluorescent lamps bluish.

PS: there's a down side to halogen lamps: they get very hot and
increase your need for air conditioning in hot weather.
Here in the east, it's getting cold so I don't mind the additional heat.
--
Jeffrey Jonas

[e-mail]