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4% light decay at 800 hours......twice?
How is this possible?

I measure with a high quality light meter after almost every viewing session, plus verified periodically with a colorimeter.

At high bulb, open iris I was getting about 1550 lumens new, and am getting about 1200 lumens now in the same config.

This is with the original lamp.

How are you measuring?

What is your foot candles, how wide is your screen, and are you using a lens / anamorphic mode, or aspect zoom mode?
Yeah I don't see how 4% is possible at 800 hours, low lamp usage or not.

Greetings,

I use a lux meter and take a single measurement at the center of the screen which is 100" diagonal. I don't use an anamorphic lens/mode or aspect zoom etc. The day that I installed the lamp the lux reading was 440 (roughly 1200 lumens). I generally measure every 100 hours. This morning's lux reading was 420 (roughly 1157 lumens). I take all readings in low lamp with a 100 % gray field test pattern, Iris wide open.

Regards,
 

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I installed that 77" last weekend. Nice TV.
I have it upstairs, and while it is an astounding picture, I still find my HT 138" scope screen+HT audio to be a far better experience.
 

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I have it upstairs, and while it is an astounding picture, I still find my HT 138" scope screen+HT audio to be a far better experience.
More immersive with audio/video, esp., audio (Atmos).

Peace and blessings,

Azeke
 

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Man, it seems like such a fast drop off. When does it level off?
25% seems steep for so few hours.
Keep in mind, you might also find lamp sample variances and differences due to frequency of lamp strikes.

In my experience, JVC's lamps/bulbs are excellent and predominantly very stable. A noticeable dip in brightness earlier on is expected. That's why professional calibrators recommend waiting a few hundred hours before a calibration is performed.
 

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JVC NX5 at 140", Denon X4200W (5.1.2) with Axiom Audio speakers + Bass Shakers
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Keep in mind, you might also find lamp sample variances and differences due to frequency of lamp strikes.

In my experience, JVC's lamps/bulbs are excellent and predominantly very stable. A noticeable dip in brightness earlier on is expected. That's why professional calibrators recommend waiting a few hundred hours before a calibration is performed.
Well in the case of my 25% drop after 400 hours, I have very few bulb strikes as I use my projector for many hours at a time. Never less than 3 hours at once I would say and usually longer per use.
 

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Calibrated best mode, my NX7 was putting out about 1560 lumens in high lamp with aperture at full open. Twenty-five percent light loss at 400 hours is a loss of 390 lumens there. That would mean a maximum of 1,170 lumens calibrated. I can assure you, I was getting close to that in low lamp after a few hundred hours.
 

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Well in the case of my 25% drop after 400 hours, I have very few bulb strikes as I use my projector for many hours at a time. Never less than 3 hours at once I would say and usually longer per use.
Does your room have A/C? I've noticed a while ago (before getting my rs2000) that in a non A/C room, during long sessions, the ambiant temp can go up and that can have a negative impact on brightness.

That's one of the reasons why I invested in A/C for the cinema room.

In small room, the PJ can contribute to a significant raise of temp that not only impacts on the calibration (especially greyscale) but also on brightness/lamp life, as least as far as I could observe.

Since I make sure that A/C is on especially during long sessions (calibration or watching), I don't notice such big drops in brightness.

One other possible reason is that when you measure brightness in respect to lamp life or to check the lamp spec, the only mode to use is high bright (profile off, uncalibrated, no color temp correction).

Every other mode can be impacted by an Autocal for example, especially if you use a poor Spyder for color, as it will overcorrect. A drop in brightness caused by a poor Spyder can be up to 15% and more if it's really off and nevertheless used for color. Using a proper meter (say an i1pro) for color can claim back that much wasted brightness.

So I only use high bright / profile off to monitor bulb life, as that's the only "factory" mode that remains "factory" even if you use Autocal. Unless you restore the INIT file before each brightness measurement, which is unlikely.

It is, by the way, the mode that JVC uses to define the specs (at shortest throw).

It is also the mode used to calculate native on/off contrast, but at longest throw this time.

When I stopped using Autocal and started using the native color gamut with a large 3D LUT (profile off with the filter), I gained another 5-10% in brightness compared to an Autocal with the i1pro2.

So the calibration isn't only more accurate, it's also brighter.

Please note: I am not saying that a Spyder always wastes brightness when used for color, or that anyone will gain brightness if they stop using Autocal. Autocal is great, it's just not my preferred way to calibrate anymore now that better options are available in my situation (external 3D LUT available for all my sources and not just for my HTPC). The need to calibrate non-HTPC sources was the main reason why I was using Autocal previously. I would still be using it today if I didn't have the ability to use a 3D LUT for all my sources.
 

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My wife and I watched Aqua Man tonight in my new HT. I chose the Mid option for Theater Optimizer because High setting was a little too bright and the colors weren’t popping. This is the first movie we’ve watched with changing aspect ratios. It actually didn’t bother me as much as I thought it would when projecting it on my 2.40 screen.


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This is where I find the JVC masking function really helpful. Most films with shifting aspect ratios are still shown 2.35 in most theatrical presentations at time of release so framing should remain fine with the top and bottom of the IMAX scenes hidden.
 

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I installed that 77" last weekend. Nice TV.
Yeah we have 2 65 inch LG’s that I love but still find the immersion from my 120” theater screen hard to beat - especially with my new RS-1000!
 

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I have it upstairs, and while it is an astounding picture, I still find my HT 138" scope screen+HT audio to be a far better experience.
Have a pretty good 5.1 sound system with it, but movies on my much larger projector setup is a much better experience, so I agree with you.
 

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ive used both the xbox one x and x box series x with my nx7 and am happy with performance.

playing rdr2 on a 120" from 12' with full surround is jar dropping.
any specific questions?
I guess my main question revolved around input lag. Any complaints?
 

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This is where I find the JVC masking function really helpful. Most films with shifting aspect ratios are still shown 2.35 in most theatrical presentations at time of release so framing should remain fine with the top and bottom of the IMAX scenes hidden.
I agree. And I love that the masking is now part of the installation mode. So once you set it up for a given AR, you'll never worry about overspill again. I'll probably be watching Tenet in 2.20:1 just to avoid the annoying change back and forth. Just wish Nolan could find a solution he's happy with to stick with a single AR. The switching takes me out of the film.
 

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Has anyone ordered AND received an RS1000 or RS2000 in the last month? I ordered an RS1000 at the beginning of December from an authorized reseller. At that time I was told it would be "Drop Shipped" to my home in a few weeks. Not getting a straight answer from the reseller as to when I can expect my projector. Anyone know what the deal is with current stock?

Thanks,
Jerry
 

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Keep in mind, you might also find lamp sample variances and differences due to frequency of lamp strikes.

In my experience, JVC's lamps/bulbs are excellent and predominantly very stable. A noticeable dip in brightness earlier on is expected. That's why professional calibrators recommend waiting a few hundred hours before a calibration is performed.
It's funny - I have a lamp with 1500 hrs on it and get about 96.5 nits peak; yet, my brand new lamp with 150 hrs gets me only 106.5 nits.

As my calibrator isn't coming until the end of the month, I swapped in my old bulb to use for now as I had reached the 150 hrs I wanted to do the calibration on new lamp.
 
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