Here's the video...

http://www.youtube.com/watch?v=mVDUJM0of1o

Was watching a movie, projector was on for about 15-20 minutes. All of a sudden images freezes and starts turning yellow. What the?

So I turn the LCD off and the video is what was happening.

Also if you guys notice there's some yellow stuff on the bottom any idea how to correct that?

I haven't seen that before, but I recently stripped the A/G off. I can also see the fresnel rings when I play with the focus. Which never happened before.

Maybe with that A/G layer removed everything's much more visible now.

Well, i'm in process of making a new box, hopefully I'll get that stuff resolved.

What are your temps like? Are you running over 100 F? Also check to make sure that you have plenty of play in your frames so that when everything heats up its not bending the LCD or anything like that. Another thing could be the connections. Have you checked all of them to make sure that you dont just have something that is coming loose when it heats up.

Just a few thoughts. Hang around and a few of the more experienced guys will be along.

The colour change after you turn the lcd off looks to me like what some LCDs do after you turn them off normally, only they do it in a fraction of a second.

I'd bet it's heat related. Temperature is the only thing that makes liquid crystals change fast or slower.

^^^ Yeah, but I know that mine take at least two seconds to go back to white. But, I do agree that it is most likely gonna be heat doing something.

Ok, problem solved. I just jiggled on the FCC wires while the thing was off, when I fired it back up it was all good.

But FCC where in that same position forever, I just don't get it why it happened all of a sudden.

I thought it was the heat myself, but no its running at 70-80. My room is very cold.

I'm thinking that the time it took to jiggle the FFCs might have been enough time for the lcd to cool. Read: I still think it's heat. I've never seen an FFC issue do that; they usually just leave coloured vertical lines on the screen corresponding to the FFC that's damaged. And that's experience with 4 LCDs worth of FFC issues talking.

Where's your thermometer?

^ +1

Are you sure that your LCD is that cool?

This is most likely a heat problem. Pictures of your build would be helpful.
When the light hits your LCD, 90+% of it is turned into heat. Your polar layer started to turn brown (the AG was likely protecting it further, before you stripped it). Once turned off, it began to cool.

I found your earlier photo album from your other thread. It looks like you have a cooling slot in the bottom of the projector, right?

The appearance of fresnel rings in a projected image usually points to the fresnel(s) being too close to the LCD.

No the slot is on the top, I built the projector using of the simple 15" plan. Got two 80mm fans out back those things blow tons of air and they're loud.

I'd think its heat related, but the projector was only running for 10-15 min. I've had it running way longer in a hotter room before, but yeah I realise that the LCD is more suseptible to heat with a/g layer removed.

But I watched 2-hour of Ironman yesturday and it was all fine.



Now what do you guys thing about that Yellow spot on the bottom? (which is actually on the top, my LCD is upside down due to fcc).



Thanks!

Heat rises. It was your polar burning at the top.