My Kodak instructions for a Ektagraphic AF-2 state that the fan switch is
only if you are going to move the projector right away. If you are not
going to move it the life of the bulb will be prolonged by letting it cool
gradually.
----- Original Message -----
From: <ClassicVW@xxxxxxx>
To: <olympus@xxxxxxxxxxxxxxx>
Sent: Monday, June 21, 1999 3:27 PM
Subject: Re: [OM] slide projector handling
> In a message dated 6/21/99 3:51:46 PM EST, cpl49@xxxxxxxxxxxxx writes:
>
> << Basically, rapid temp changes are bad for filament life. The 'fan only'
is
> there and should be used if a bulb blows during a show and you want to
> cool it as fast as possible so you can handle it (paper towel or cloth so
> you don't transfer oil to surface). HTH,
> >>
> It's kinda like your computer, it gets its most stress at startup,
> but some things you can't avoid altogether.
> Generally, the shock required to break a hot filament is much less
> than the shock required to break a cold filament. This is because the
hotter
> the temperature of the filament, the easier it stretches, or deforms; and
as
> such, it will stretch to a point where it breaks. Let's say your filament
is
> cold, you'd probably have to drop the projector all the way to the floor
to
> break the filament. But, aside from normal aging, the filament will break
> with just jostling the projector if the filament has reached incandesence
> (being lit). So, I would still run the "fan only" for a few minutes after
a
> slide show, no matter if the projector is from the '70s or '90s, regular
> incandescent bulb, or halogen bulb. The major difference between a regular
> bulb and a halogen, is the halogen burns at a higher temperature (which is
> possible due to the filament being tungsten). Higher temp.= easier to
break,
> BUT the tungsten filament is stronger than regular steel, so it's a wash
as
> per heat vs.strength, so I'd still try to cool the bulb (filament) as soon
as
> I could even though it's a halogen. The cooler it gets, the less likely it
> will be to break easily. Why keep it hot longer? Cool that sucker- fast.
>
> George S.
>
> < This message was delivered via the Olympus Mailing List >
> < For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
> < Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
>
>
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|