Originally Posted by kutlow
a few months back I calle JVC and talked to a tech there. This was when people on this forum mentioned that 1300 lumens is at 8500k. The tech insisted the 1300 lumens is at d65. So from what I gather either he lied or was misinformed right?
Just a quick comment to clear up a few things that have been posted.
JVC does not specify the color temperature at which the lumen measurement is made. Anyone who tells you otherwise, does not have their facts right. Having said that, the factory was very clear that the lumen measurement this year is done using the same methods and the same settings as that in previous years. I also think that most people that have seen the new generation and compared it to the older generations will agree that there is a very visible increase in brightness.
While we're talking about color temperature, keep in mind that there can be a big difference between 6500K and D65. As someone pointed out to me recently, 6500K is simply a line on a graph. D65 is a very specific point on that line.
Also, keep in mind that the lamp is rated for 3,000 hours (using standard lamp mode. If you use high lamp exclusively, plan on about 2,000). That is based on the 1/2 life of the lamp. I spoke with one of our senior engineers last week just to confirm that nothing has changed, and he said it is still correct. This means, that at 3,000 hours, the lamp will be down to 50% of it's original brightness.
By the way, I'll add in all the usual disclaimers. Every lamp situation is different. The break-in period is very crucial. Decreases in brightness are usually not linear. After about 100 hours, things stabilize pretty nicely. Power failures during operation are a bad thing and affect lamp life in a negative way (sometimes very negative). Individual usage patterns absolutely affect how long your lamp will last. The lamp is considered a consumable item, so you may or may not get 3,000 hours out of your lamp. This year, more so than in the past, people will use a blend of standard lamp mode for 2D and high lamp mode for 3D, which will also impact the number of hours you actually get. Etc. Etc. Etc.
Yes, to get full brightness you need high lamp, open aperture and short throw. Of course, as pretty much everyone understands, those are all exactly what you don't want for maximum contrast. The point is you can install the projector to match the requirements of your room and your viewing preferences. A lot of people pick a setup that is somewhere in the mid-range of both.
Having said that, my personal experience leads me to believe that there is no reason to worry about being down to only 400 lumens after just 500 hours of viewing.
Lastly, I'm very happy to see that the vast majority of posts from people who have taken delivery of these projectors seem to be very, very happy with their purchase. That's the thing that matters the most.