[klover]

I've been running a Infocus IN72 since April of this year. About 60 hours on the bulb.


Source never changes (Nvidia 7900GS, 1:1 Pixel Mapping).


Same screen, room lighting, bulb power setting, brightness/contrast etc.


But, from one weekend to the next, I *swear* different power-ups give me different levels of brightness. Noticeable changes.


For the last few weeks I've just chalked it up to different movie transfers but I watch the opening to Star Wars III practically every time I turn the projector on (a guilty pleasure) and have noticed this.


So, long post short, can a bulb hit a slightly higher/lower level of brightness from power-up to power-up?

 

[Silverfox1]



Quote:
Originally Posted by klover /forum/post/0


I've been running a Infocus IN72 since April of this year. About 60 hours on the bulb.


Source never changes (Nvidia 7900GS, 1:1 Pixel Mapping).


Same screen, room lighting, bulb power setting, brightness/contrast etc.


But, from one weekend to the next, I *swear* different power-ups give me different levels of brightness. Noticeable changes.


For the last few weeks I've just chalked it up to different movie transfers but I watch the opening to Star Wars III practically every time I turn the projector on (a guilty pleasure) and have noticed this.


So, long post short, can a bulb hit a slightly higher/lower level of brightness from power-up to power-up?

With your statement in regards to actually seeing the brightness INCREASE with the same exact variables it is possible the circuitry in relation to D.C. voltage levels & current flow is changing slightly and not being held to the exact same level between start-ups caused by the projectors pwr. supplys voltage regulators, rectifiers, or a capacitor. This is something a service tech would have to bench check taking measured readings between start-ups.


I realize your video card is a high end model but try if you can changing to a different source using the exact same opening scene several times. You should notice the same difference in brightness if your Infocus is the culprit. A weeks time frame between startups has nothing to do with your issue.


You should experience normal lamp degradation over time seeing ONLY diminished brightness unless the above mentioned is changing out of there respective voltage tolerances which in these low budget FP`s is probably + or - 2%.


Call your service tech & explain your scenario.


Regards,

 

[klover]

Yes, the brightness increase (as opposed to bulb decline) was what struck me as odd. I should also add that I had the not-so-uncommon bulb flicker issue when the bulb was set to run on low power.


Thanks for the information. I'll definately keep an eye on this.