BigD 3854 SLA bulb fogged reflector

cnee

Newly Enlightened
Joined
May 4, 2004
Messages
39
Location
San Jose, California
I have a Pelican BigD 3854 SLA 4.0A bulb in a Mag 2D with 2 x 3AA-to-D (rechargeables) and Fivemega's LOP reflector. It is pretty bright but after a few minutes, it gets warmed and deposited something on the reflector which fogged up the reflector. After a period of cooling, the reflector did clear up a bit but was left with what appear to be water marks all over the reflector. Ruined my favorate reflector. /ubbthreads/images/graemlins/mad.gif Anyone else had similar problems with the BigD 4.0A bulb?
 
Condensation is an issue with certain combinations of bulbs and reflector sizes. My E2e-SG has this problem, as does my Mag85. I suspect it has something to do with the ultra high powered bulbs being able to heat a given volume of air (small bulb, small reflector, large bulb, larger reflector) inside the air enough to cause condensation on the reflector surface.

None of my other incans have this problem, such as the SF P60, P90, and 91 that I own.
 
I've found I can remedy this by applying another highpowered light to the front of the light that is fogging. This will evaporate any condensation. Then (ok this sounds weird), right before I reassemble the light, I suck the air out of the head and I don't have anymore fogging.
 
[ QUOTE ]
Luna said: I suck the air out of the head and I don't have anymore fogging.

[/ QUOTE ]

Um, how do you do this?
 
Later last night I tried the same BigD bulb with a stock Mag reflector, it did the same thing to the plastic reflector. But with a smooth reflector, the fogging did not clear up, it just stay. I was indoor (heated) all the time, same as before.

By the way, I have been using the GH-24, the KPR-xxx, and also a 12V 20W halogen bulb (with 11 Nimh cells) in combinations with 3 different reflectors (the Fivemega 3" LOP, Fivemega's regular Mag LOP, and the stock Mag) indoor or out but never seen the problem before.

I am curious about how to suck the air out of the head also...
 
Must... resist... urge... to... comment... /ubbthreads/images/graemlins/mpr.gif /ubbthreads/images/graemlins/mad71.gif
 
Well the good old fashioned way, with your mouth. Just create a vacuum (your doing it right if you look like my post icon). Granted it works for my SLs, SFs and mags, but might be more difficult sucking the air out of the BigD ( /ubbthreads/images/graemlins/evilgrin07.gif stop it!! /ubbthreads/images/graemlins/mad71.gif) . A foodsaver container might be the best choice.
 

Latest posts

Top