I got a Barco 909 recently. The green image appears dirty, both on the screen and inside the tube. It is most striking when you compare a solid green pattern with a blue or red one, which are both very clean. The pattern does not move at all with content, so it must be optical rather than electronics.

Here are a couple of pictures. The green/purple image is a screen shot of a stripe test pattern from my dvdo.

Has anybody encountered this issue?

I just checked my Runco DTV-1200 (Cine9) and did not see the dirty image. I just changed the green LUG and reused the fluid and was worried about a couple of floaters. I used the pattern from DVDO also.

Do you thing it might fungus?

That is the phosphur grain.

That means it is focused. Read the Guy Kuo Holy Focus guide.

Mark, looking inside the tube to avoid the optical focus step, the green is very different from the other two. The pattern is much bigger than the other two, and the streaks are a bit dark. How much grain is there normally, and is it common for the green to be rougher?

Am worried it might be fungus. It is inside the tube, as looking at the surface with a flash-light with the PJ turned off it's clean. That being said, looking at the pictures on the Curt Palme's site

http://www.curtpalme.com/Fungus_Removal1.shtm

, I don't have any of the focusing issues you see there.

skylooker, do you see the phosphor grain? Would be curious how big it is, as you have essentially the same PJ as I.

Is the green a rebuild or an original Panasonic tube?

It could be a fast Phosphor LUG Green tube

It's supposed to be the original one, about 1500 hrs. Any way to tell for sure whether a tube is a rebuild?

My first thought was that it was grain too. But that's A LOT of grain I think. How 'big' are the areas in your pictures you posted?

Kal

I also have a Runco DTV-1200/Cine9 and I don't have any hint of this green issue.

Bob

This set came from me, and it came out of a HT install with 1500ish hours on it. I carefully checked the set before selling it, watched it in the original owner's HT for about an hour before buying the set and saw nothing like this. I was trying to figure out whether it's fungus or phosphor burn or phosphor grain...

FWIW Curt, this doesn't look like phosphor grain to me. It has an appearance similar to the VDC rebuilds when they first started doing them and weren't getting the phospher coating on correctly.

Terry

It could be a fast Phosphor LUG Green tube

This isn't what the grain look like on the P43 tubes.

Terry

Just a few thoughts...possibly helpful, maybe not.....

Would it be possible to pull the lens off and get some pics?
With the PJ off, and then with a very low contrast
white field? to get an idea of what is really in there, or not...

I am also wondering if this could be an electronics issue,
maybe something as simple as cleaning the pins on the tube,
or try swapping neckboards? After checking with Curt, of course.

Regards,
G

From what I remember that set was completely stock, no rebuilt tubes in it. It only has/had 1500 hours on it when I got it, no tube wear whatsoever.

I did nothing to the set, just ran it here to make sure it was 100%.

Well - since the PJ just recently checked out fine at Curt's,
then maybe it would be worthwhile to check the things
that are different in the new set-up. Perhaps a quick test
would be to just swap the input connections between green
and red (and/or blue), and see if the issue follows the input.

G

On an 110" wide screen, some of the the darker smudges are about 2mm wide and 1-2 cm long --- big enough to see from 18-20 ft. It worse in the middle of the screens compared to the sides and corners.

I have already tried to switch the cables to see if the issue moves to a different gun to rule out the rest of my equipment. It stays with the green.

Is it possible for the electronics to cause something that does not move at all? I marked a spot with tape on the screen, and it is the same no matter what I played. Also it stays in the same place as you move the image up and down with the raster shift.

I'll take the lens off and take a look.

Andrei

From my experience 'noise' such as that would be dynamic if it was caused by the electronics or video input. If the lens has been eliminated the tube itself would be the source of the problem.

I took out the lens and the problem does not seem in the fluid or on the glass or tube surfaces. Turned off the tube seems perfectly clean. Turned on I see the imperfections as part of the image. That would exclude fungus I presume.

I attached a couple of pictures. The first one is with the unit off. The second is a test pattern from my dvdo, a grey rectangle about 1/3 x 1/3 of the screen, on black background. This shows the problem. It's not the diagonal-like bigger pattern (which might be a photo artifact), but the finer darker areas, some of which you can see in the middle of the picture bunched up a bit like vertical lines.

My previous post describes the size of the spots as seen on my screen --- how big is phosphor grain supposed to be?

you may want to have a look through the lens
just to rule out any odd optical effects, though it seems unlikely.
Look through the lense or swap it with another. Hopefully the lense and tube didn't sit in the sun and cook - seems unlikely as well.

Surely the tube isn't dry from lack of coolant either?

If you bring up an internal set of grids, how do they compare?

Mark

I can see two distinct black spots on that tine face. One at 6 oclock and another at 8. These spots are phospher problems (phospher is missing). There are a few more there if you look closely.
This would lead me to believe that there _may_ be other phospher problems as well related to the mottled look of your G tube when projected.

Terry