Film-Tech Forum ARCHIVE: NEC 2000C pink trouble

This is topic NEC 2000C pink trouble in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Jerzy Gwizdz (Member # 8819) on 02-10-2017, 03:52 AM:

Hello
What can cause this problem
Pink stain on the screen
Photos

Thank you in advance for your help
[beer]

Posted by Carsten Kurz (Member # 5396) on 02-10-2017, 08:51 AM:

Jerzy - your problem is, you are mistaking a NEC 2000C for a Sony, because, as per forum policy, this can only happen to Sonys, but never to DLPs.

So, please have another look at this projector's number-plate and confirm your error.

Regards - Carsten

Posted by Marco Giustini (Member # 4544) on 02-10-2017, 09:04 AM:

Carsten: LOL!

I believe Mark posted a similar issue with a small 900?

Posted by Mark Gulbrandsen (Member # 72) on 02-10-2017, 09:48 AM:

Check the prism for some goop of some sort. On the NC-900 a bug had gotten stuck to the rear side of the face of the light inlet prism. That bug eventually disintegrated and the problem at that site is now barely visible. If you run a popcorn popper, then this one may have pulled in come oil that is contaminating the prism. Wrong offers a cleaning service for NEC prisms at the ludicrous price of about $2500+. Your tech may also be able to clean it depending on how resourceful he/she is and if the contaminated surface is actually accessible or not. Could also be something on the lens. Best way to tell is to turn on the DMD's one color at a time to isolate which DMD is causing that. Then it will be very obvious. Except for having to be extremely careful with the giant 6000 pin plug, the NEC light engines are probably the easiest of all to pull for inspection.

Mark

Posted by Marco Giustini (Member # 4544) on 02-10-2017, 10:35 AM:

good idea to check colour by colour.

Easiest? Have you ever removed an engine on a 515? (Carsten, I'll need your help very soon! [Smile]

)

Posted by Dave Macaulay (Member # 813) on 02-10-2017, 12:18 PM:

With any projector it's massively easier than on an 1100L.

Posted by Mark Gulbrandsen (Member # 72) on 02-10-2017, 02:03 PM:

Add the NC-900 to the NC-1100 list! They really bury those down inside, like 5 sub chassis down! NC-1200, 2000, 3200 and 3240 are all very easy to pull the engine. Literally a ten minute job.

Even a 1978 Chevy Malibu engine is easier to pull than an NC-900 or 1000 engine is.

Mark

Posted by Steve Guttag (Member # 268) on 02-10-2017, 08:16 PM:

Magenta means that green is blocked...look to that imager to have dirt in its path.

Posted by Jerzy Gwizdz (Member # 8819) on 02-11-2017, 04:22 AM:

Carsten- this is NEC 2000C worked 30,000 hours

My local service can not clean the prism
can remove and send it to the manufacturer
It's a very big cost
for now it is not visible to watchers

question - will it increase?
Regards

Posted by Mark Gulbrandsen (Member # 72) on 02-11-2017, 10:22 AM:

Yes, it probably will get worse. It's caused by the fan above the light engine blowing crud that makes it past the filter into the engine prisms. NEC SHOULD HAVE put a filter on that internal fan!!

I suggest you call another more experienced Tech and consult with him or her about cleaning it on site.

Also, if you have popcorn popper (or similar)that is not exhausted outdoors then that is the likely culprit. I have seen popcorn oil dripping off components inside of Christie projectors.

Mark

Posted by Marco Giustini (Member # 4544) on 02-11-2017, 10:50 AM:

as mentioned before, filtration on NEC machines is mediocre at best. Christie have a much better system. Barco don't care as their engines are (supposed to be) sealed. The DMD's, Mark, not the engine itself.

I heard mixed info on NEC's: are those engines supposed to be sealed or not? My limited experience says they aren't.

Posted by Mark Gulbrandsen (Member # 72) on 02-11-2017, 03:44 PM:

Depends on who's filters you use. If you are using the cheap chinese filters you get cheap results. Some of my customers that use them add foam tape to the edges of filter to seal it to the projector better and between filters. This helps immensley. The NEC true Heppa filters work really well, but are almost 30 USD a pop. I have NEC's in many desert areas and the lack of dust in them is amazing to say the least. Most still look brand new inside, absolutely no dust.

Dust buildup is any electronic components enemy and will shorten it's life. Its the main reason I do not like Barco. They can seal the light engine up all the want to. But I've seen up to a 1/8" thick coating on talcum like dust circuit boards in Barco's with metal filters that came out of CA. The dust also shortens fan life. Yes, the newer ones are better having done away with that useless metal grate filter. On Christies the Electronics compartment stays clean. But the lamphouse is another story. I've had popcorn oil dripping off Christie lamp supports on more than one occasion. Thats a horrible mess to have to clean up.

Mark

Posted by Marco Giustini (Member # 4544) on 02-11-2017, 04:27 PM:

quote: Mark Gulbrandsen
Some of my customers that use them add foam tape to the edges of filter to seal it to the projector better and between filters. This helps immensley.

That's tweaking and as such does not qualify.

No digital projector is supposed to be used in a place where - with mesh filters in place - a thick coat of dust deposits between service intervals. I do not blame Barco.

And I've seen an NEC - with original NEC filters - with a totally contaminated engine.

Either you do like Christie and put some efforts in filtering the air entering the engine or you seal the DMDs' area.
Sorry but putting the filters on plastic frames, sitting on metal slots with no gaskets is just plain wrong.

Posted by Jerzy Gwizdz (Member # 8819) on 02-12-2017, 04:04 AM:

Thank you for your help
Generally filters change frequently and our NEC is clean but sometimes the filters are not suitable
Popcorn is but further away from the projector
For now we are waiting for further developments
All the best

Jerzy [Smile]

Posted by Carsten Kurz (Member # 5396) on 02-12-2017, 07:04 AM:

After 30.000 hrs, every projector has a right to discolor to a certain extent, no matter wether the filters have always been changed on schedule or not.

Sometimes, you may get rid of it by cleaning, sometimes, especially after long operating times under high brightness, you may need to change some optical parts.

- Carsten

Posted by Mark Gulbrandsen (Member # 72) on 02-13-2017, 12:40 PM:

I have not encountered any great shifts from optical component shift of any NEC's as of yet. The little shift I have seen is likely from dirt accumulation on the light engine. Most of my customers are at about 15K hours run time. A couple are a little higher than that. If there is any shift to happen it's going to be to the IR filters and fold mirror which are multi-layered mirrors. The lamp reflector and integrator shouldn't change unless you physically change out those parts.

Mark