Audio and color on NEC NC900C

[Agnius Acus]

Maybe, as Leo has mentioned, you’ve got a bad batch of lamps if everything looked fine before. If you asked me, 7 meters is a pretty optimal size for 900, even if the screen has a low gain. Removing the notch filter would visibly increase brightness.

It doesn’t matter if the color space meets DCI targets if you can’t provide enough brightness to maintain all the details in the picture. That’s my stance.
Contact your local NEC/Sharp representative if you can’t find the dummy filter. Don’t worry, it won’t ruin picture quality. But you’ll have to recalibrate the projector for optimal color balance. Without it image will have a blue tint.

On the other hand, what is more likely, is that Nosferatu is simply too damn dim for these low brightness/low contrast type projectors, as was Batman. It just made those shortcomings more obvious.

[Rodrigo Wilson]

Thank you Ryan, I managed to automate the audio processor with the JBL commands that were in the program folder, on a TXT file.
As Leo mentioned, a technician came today and took a look at the projector, he removed the lamps and told me that he should change the integrator rod, that they´re damaged.
So tomorrow or the day after he´ll come back and replace it.
I hope that fixes it.

[Carsten Kurz]

A colleague bought genuine NEC lamps for his NC900 last year - both were crap. One delivered maybe a third of the spec'd light, and the other was defective within a few hours. Even if you buy genuine NEC lamps now, you should use a light meter to check if they are good at least as far as initial brightness goes.

[Agnius Acus]

Those probably spent too much time on the shelf, which is not surprising, as there is ever-decreasing demand for that specific model.

My technician and I did an A/B test between brand-new genuine and non-genuine lamps, with something like 100 hours of usage on the latter. The difference at full power was 1 lm. With 300 % lower price, it is well worth the risks involved.

[Mark Gulbrandsen]

Am pretty sure the Chinese have a Laser lamphouse upgrade for the 900 and 1000. They also have a Rep here in the States as well. So, as far as increasing light level, that's about the only option.

[Ryan Gallagher]

Rodrigo, also instead of subjectively judging brightness using features and trailers... I would instead get familiar with what your built in test patterns and full field colors look like. The greyscale ramp ones can also be pretty handy for spotting brightness issues too. A full field of white or color can also show you field brightness uniformity problems.

Since you have a couple other screens that "presumably" are subjectively closer to DCI brightness standards... you can A to B compare with some test patterns walking between rooms. This will be far more conclusive if you spot major differences than using the "x film looked dark" method. ;-)

Short of having a meter to measure with of course.

Features and Trailers are also great if you become familiar with what a particular one "should" look and sound like under correct conditions. Keep a favorite around on all machines for quick reference when something seems amiss otherwise.

[Agnius Acus]

As per „Sharp/NEC“, regarding retrofitting laser:

It is important to note that whilst it is possible to replace an existing projector light source with a new laser light source, the remaining components will still be aged. Any projector component more than 10 years old will be susceptible to failure. It does not make sense to invest in a new laser light source only to risk failure in other parts.

[Leo Enticknap]

From the cut sheet attached above:

We strongly believe that it is in the best interests of the cinema operator to replace older lamp-based projectors with a new Sharp/NEC laser projector.

No ... really? I guess that rules out a Barco or a Christie, then.

I actually agree with the advice given: in the absence of unusual circumstances (e.g. the projector in question is low hours and has been scrupulously maintained), sinking $5-10K into a decade-old projector is likely not sensible if it can be avoided. I have tried to dissuade customers from doing that many times. But it should be noted that the authors of this sheet have a vested interest in giving that advice.

[Steve Guttag]

I could never make the numbers work until you get into the 4KW and above range. 3KW is sort of on the bubble. When you look at the cost of 2KW lamps and smaller and combine that with the lamp life, there is never a payback for going laser on them. You'll be changing phosphor wheels before you reach payback on switching away from lamps. And that is before you realize that you could spend a lot of money on a projector that could get a stuck pixel the day after the conversion, setting you back a ton more.

Now, Barco does offer the ability to extend the warrantable life of their projectors to 13-years with one of their laser retrofits...so there is some piece of mind. We figured that the sweet spot was if you caught the lamp based projector in year 6 or 7, then, you have, roughly, half of the projector's life left and the opportunity to keep it warranted for piece-of-mind. But if you have a 10-year old projector you are getting ever closer to an expensive repair bill. The laser conversion isn't going to keep you from it.

[Carsten Kurz]

Why would these bulbs suffer from excessive shelf-life? We use the same USHIO bulb type in our Sony, we buy them in packs of six. They often sit on our shelf for 5 years until the last one is used up, and they show the same performance as the first one. Also, if they last multiple years when used daily with a decent brightness fall-off, why should they suffer from storage alone? Maybe NEC is now putting in 'chinese' bulbs instead of USHIO made bulbs?

[Agnius Acus]

I'm wondering the same thing. The biggest brightness difference I have ever encountered between sets of new lamps was almost 20 %, basically defective units. The brightest ones, which were on par with the original ones, sat in the storage for 9 months after buying them.

[Mark Gulbrandsen]

Has this projector's optical system ever been serviced? 900's are notorious for getting dusty inside, especially if your customer has switched from Heppa filters to some common off the shelf stuff. Back when the lamp explosions were happening in them, I had a the light input glass part become scratched. It did not affect the sharpness color of the image on screen, but it did noticeably affect the light output from that lamp.

[Leo Enticknap]

Why would these bulbs suffer from excessive shelf-life?

My guess - and I stated in my earlier post that this is just a guess - is that the pressure seal on the bulb needs periodic lubrication by the expanded gas within to maintain proper pressure, and/or that it simply degrades over time.

It's the same principle whereby the manual for my car advises that the air conditioning pump be run for at least 10 minutes every week in order to keep the seals lubricated. I have done this (even in the depths of winter). The a/c still works fine, and has not needed any refrigerant top-up, in the almost eight years and 233k miles that I've had the car. In contrast, I know someone who bought a new car of a similar model and did not even run the a/c until two years later (after moving from North Dakota to Southern California, hence not needing the a/c previously), only to be hit by a blast of warm air and the need for a new compressor.

The lamps we sell, both xenon arc and mercury discharge, come with a warranty for a specified number of burn hours or two years, whichever comes first. This is why we advise customers not to keep more than one new spare lamp in stock, especially if their projector runs significantly less than multiplex hours (8-12 hours a day, seven days a week). Any others will likely be warranty expired by the time they are actually used. I once had an argument with the director of a nonprofit multi-purpose arts center venue that had underspent on a grant for something else, and rather than have to return the unused money, wanted to buy five spare xenon arc lamps for their projector. They were only running their projector for about 500 hours a year! I managed to convince them that replacing their 1960s vintage house lights dimmers and upgrading to LED fittings was a far more sensible investment.

[Mark Gulbrandsen]

Leo, Once the issue with the lamps was fixed, I never had a single problem with lamps over about 30 screens. All but one location is still open and using them.

[Carsten Kurz]

I know Xenon lamps can be stored for two-digit years without issues. It's important to clean them with alcohol from any residual adherences, grease, etc. that may have built-up over time in the booth before use, as these may prevent proper ignition.

We never had issues with the USHIO UHP Lamps that sat on the shelf for many years, after Sony/NEC/USHIO solved the initial early failure problems.

The two NEC NC900 lamps that both were crap had been delivered from a NEC cinema dealer shortly before I put them in. One delivered only a third of the normal brightness, the other one died after a few hundred hours. Not funny, as the price was nearly twice of what it was earlier.

I would advise to buy a cheap lux meter from ebay for 20-30 US$ and do comparative measurements of white when changing lamps in order to find crap bulbs before warranty runs out.