Please post experience of JVC HD750/350/550/950 bulb lifetime / lamp brightness drop

I can't speak for the JVC line, but a couple of years ago I tracked about a dozen lamps in various projectors. The average was about a 50% decrease in brightness right around 500 hours. After they reached the 50% point I stopped tracking them, as I personally consider that the point where they need to be replaced. The longest lasting lamps back then were from Sim2 and the shortest ones were from Optoma. YMMV....

This is the main reason that I'm going to wait for an led (or laser)-illuminated product before I upgrade again. I would be happy with even 500 lumens if it remained that over its (long!) lifetime.

I agree - I've bought my last bulb projector ( but probably not my last bulb ! ). You can get 600 lumens now from an LED projector ( SIM Mico ) which isn't too bad considering it only loses 5%. Unfortunately, that would barely work for my screens now. I'd prefer 800 - 900 lumens.

I'll have some numbers later this week on how much light my Lumis has lost in 300+ hours - it's lost a bit.

As I'm still trying to talk myself into getting one, I'd be interested to know Craig.

I have just over 600 hours on my bulb and had my HD750 calibrated this weekend. We had to turn up the bulb in order to get a proper calibration since the bulb had dimmed considerably. At this rate, I will probably have to replace the bulb at 1000 hours...not the 1900 it is said to be rated for. Not to mention will have to have a tweaking done on the calibration as well. Please let me know if anyone has a reliable source for bulb purchasing.
Thanks.

This is one reason why it's hard spending $4k-$5k for a projector when the bulb dims so much. I didn't have any issues spending this on a top end plasma but it's disappointing that FP quality changes because the bulb dims at such a fast rate. Thankfully my average seems to be about 250 hrs/yr on my bulb (FPJ1) since I only use it for movies.

I have never used a projector yet that I didn't have to change out the bulb well before it's stated life ( or anywhere even close ). Loss of brightness, or using " too big a screen " ( or both ) is IMO front projections " dirty little secret ". I don't think I've gone beyond 500 hours on any projector before putting a new bulb in except for my dVision 1080p ( which uses 1 or 2 bulbs at the same time - I still changed out the first bulb at 875 hours with both running ).


After W. Jeff Meier finishes up tomorrow, I'll post some numbers.

I figure once the two calibrations are out of the way, I will have the used bulb numbers and the new bulb numbers set. Then, at my current rate, it's a new bulb every 18 to 20 months ($300)....you can spend more than that in a month taking a family of four to a couple of movies. Plus, you have a better experience, no gas and the image is beautiful...without the soda stains on the screen or the floor.

My RS20 bulb lost the majority of its brightness (don't have the numbers in front of me, but I think it was something like 70%) by the 550 hour mark. Definitely sub par performance in this regard compared to the other SHP, UHP, and Xenon bulb pjs I've owed in the past.

BTW, the amount of gamma and grayscale drift on my projector is extensive. Even with 400 hours on the bulb it was drifted considerably after the next 100 hours. It was the same was with my RS1.

I don't recalibrate it as often as I should, because to get the gamma right as well as the grayscale right all the way down to 5%, it takes several hours and is exhausting. But IMO to get the best performance one really needs to have the equipment, proper software, and know-how to do this on their own.

Does anyone have numbers that show if bulbs age slower when used at lower brightness? I have a Silverstar screen that allows me to keep my RS-15 at its lowest brightness setting and still have a great bright picture. My hope is that my bulb will last longer, i.e. lose less of its brightness over time...

YAN

FWIW - regarding my post just above - I run in the Normal lamp mode (not high).

I found with my RS1 if I use normal lamp for most of the life of the bulb and it has dimmed significantly that the bulb actually gets brighter if I switch to high lamp for several hours then back to normal lamp. Normal lamp after several hours on high will be brighter than before I used high lamp. Plus its stays at higher levels for several uses after. I noticed this with a bulb that had 1000 hours on it already but a friend of mine noticed it with a bulb that got dim in the first 200 hours. The lumen of each color shifts a lot on these bulbs over time. You should calibrate every 200 hours and even sooner if you can. The bulb I have now lost a lot of lumen in the first 100 hours and after I hit about 200 hours I switched to high lamp, calibrated and will stick with high lamp until my next bulb. Projector is in a projection room so the fans are not noisy enough to be a problem.

I think I've hit 1600 hours on my IF777. Still has 1000 lumens It's it's first bulb and I have 2 spares. Haven't been compeled to swap, and put the ND filter back on.It's why I still have it I guess. It was the first PJ I was perfectly content with. Still am at least to the point that upgradeitus isn't the thing it used to be.

What kind of screen material and what size screen??

My old Sony and Sharp bulbs were about the same. Varying degrees of brightness when new and some held there output lumen longer than others. I've been dealing with bulb projectors since 1995.

I'm almost 500 hrs into my RS1x and i still have to use a 4x ND filter on my 96" high power. Otherwise the thing is blindingly bright and makes black levels seem as if they were from a cheap DLP projector.
I'm using normal lamp (low). I'm pretty sure i could light up a 133" neutral gain screen with this thing and not feel it lacked brightness, we'll see down the road though. But so far so good.
If anything it kind of makes me regret i got an RS1x instead of an RS2 or RS2 clone for about the same price, since i would probably still have brightness to spare, but i'd get better contrast.

I'm wondering if people that are having these brightness drops turn it on/off a lot.
Personally, if i turn on the projector, it stays on for the rest of the day i watch anything on it. (sometimes up to 10 hrs+) I don't know how much truth there is to repeat on/off cycles dimming the light bulbs faster since i can't really do an experiment, but so far brightness seems to have dropped to what i think should be within spec. (it's too bright with out the 4x ND filter on my HP, and i'm @D65)

96" HP and middle of the range throw distance? That is bright for sure!

I am at max throw on a 120 inch screen but need gain. A new bulb gives me about 10ft-L but I have a Draper M2500 with about 1.7 gain which gives me approximately 17ft-L when the bulb is new on normal lamp setting. Your screen gives you probably well over 2.0 gain and well over 20ft-L and maybe even well over 30ft-L without your ND filter. After a couple hundred hours mine settles in around 12-14ft-L with my screen gain. No ND filter required.

Ron

It's funny how just 2 years ago the forum was in a panic over supposed excessive dimming of Optoma H78 and H79 projectors. Now it seems the same thing is starting to happen with JVC projectors. It's nice to see that a few experts have chimed in with their experiences, to quell the panic.

The PJ industry as a whole is very guilty of misleading the general public about bulbs. My experience, and what I've read, leads me to believe that it's a very rare PJ that has the bulb life the manufacturers spec. It seems to be the norm that the bulb will dim 15-40% in the first 100 hours and at least 50% by 700 hours if not sooner. Yet I've never seen one manufacturer give a customer this information.

I lost about 50% after 220 Hours, and started a thread about it a couple of weeks ago. Here is a link.

Part of the problem is that lamp life is not seen as a performance spec that generates much excitement. There are measures, regarding thermal and power management, that can extend lamp life significantly. Unfortunately that takes expertise and incurs cost. Not many companies are technically able and financially willing to implement this.

At the end of the day its simply not a thing that gets J6P excited, thats why it gets little attention from most companies.

Yup...I don't think this problem is limited to JVC. After tracking brightness of bulbs in machines from several manufacturers, I simply came to the conclusion that any one bulb will last me ~500 hours, and anything over that is gravy. Of course, the OP's bulb life seems really bad to me, and I would definitely complain to JVC about this. I had a really bad Xenon lamp in my Sony VW-100 a few years back, and when I cited their owns specs, they had no problem sending me a free replacement of the very expensive Xenon bulb. Just be sure to be armed with ACTUAL MEASUREMENTS starting at day one if you want them to take you seriously. I don't know if it still applies today, but back then a lamp was considered "spent" when it reached 50% brightness.

When you consider the after purchase expenses of any projector, in most cases the single largest expense is depreciation, and the cost of a new lamp is small potatoes next to that. Even if you were to use 2 lamps in a year in the JVC projectors (assuming an average price of $300 per lamp), the $300 loss (one lamp came free with the projector) is much smaller than the $2000 (minimum....usually considerably more) depreciation hit the projector takes when next year's model comes out.

Could you not also argue that the lamp is a "hidden" source of revenue for the manufacturers. Since the consumer isn't demanding improvement why improve the lamp when the consumer comes back spending $300 bucks every now and then......

You have to remember that AVS is the largest seller of JVC projectors in this country. This forum is frequented by many people that bought their stuff from them and spends significant time calibrating and measuring this stuff. Many people that just buy a PJ is not going to spend time here nor will they measure things continously. I don't know if JVC is worse or better than others, but I do think the JVC owners are overrepresented in the $3,000+ forum and therefore you will get their measurments making it look like the JVC is worse.

The PJ manufacturers dont make the lamps.

The areas I mentioned, where lamp life can be extended, are methods that the PJ manufacturer can implement. Very few do.

That doesn't make statistical sense. The larger sample population would actually help generate a more accurate answer.

True but like I said I have seen the same with bulbs for Sony and Sharp projectors over 15 years so all bulbs vary quite a bit. Some people are luckier than others and get good bulbs. My first RS1 bulb only lost about 35% after 1000 hours but the color temp shifted too much in the first 3 hours it was on so I shelved it to use as a replacement if one burns out on me. My new bulb is already 35% down after 200 hours. Bulbs just suck! We all have to deal with it until LED or some other technology replaces it.

I remember with my Sony VW10HT I had one bulb that lasted 2400 hours before it was too dim then another laster 1350 hours and another only 800 hours.

Ron

I said it before: What we need is some clever guy coming up with a LED light source for the JVCs! IIRC a fellow AVS member (I think 'Highlander' from Italy) did some test in this direction. The HD750950/990 has a powerful enough CMS to even handly any sort of spectral variation.

P.S.: I have also experienced dramatic brightness loss with several JVC bulbs. However, if you are lucky and get a good one some can be more stable than others. Very annoying in any case.

You got me beat on everything HT related, but lets not discuss statistics

To summarize my post (ie what I actually said) there is no way to read this thread and draw a proper conclusion that the JVC's are worse than other projectors. 1) The thread was written specifically to discuss JVC's. 2) There is no data in regards to other projectors 3) While a larger sample is more correct I ask compared to what? There is no comparison using numbers going on here.

I did not argue that the JVC does not loose brightness. If that was the argument then you would be correct. I simply stated that the conclusion drawn in the post I replied to was incorrect and my reasoning is correct for that statement.