JVC RS40 Lumens - Page 10

I've read about lamps wearing over time and developing either a flicker and/or dimming because the tungsten wears such that multiple arcs are created inside the lamp. Supposedly running such a lamp on high mode for a while helps, because it causes the lamp to normalize back to a single arc (somehow). I have no idea if that applies to this generation of lamp, or if it has anything to do with your particular unit. Maybe you had a funny arc out of the box, and over time it is actually evening out and/or improving to a more consistent arc as it wears? Pure speculation.

Either that or your light meter is acting funny?

Hi,

If my meter is acting funny so are my eyes, since the image has never looked brighter.

Larry

In the end, that's all that really matters.

What are the specs on the new model

REFERENCE SERIES 3D HOME CINEMA PROJECTOR DLA-RS45U

So the specs claim the same 1300 ANSI lumens that the previous entry-level projector claimed. However, these specs don't state whether the projector is in a usable picture mode. No one that I know of has been able to measure 1300 ANSI lumens on the RS40 in a watchable picture mode.

Larry

P.S. For the Procision Series (DLA-X..) the entry level projector has 100 more ANSI lumens than the more expensive models. I don't know whether this is merely a typographical error.

Out of the box lumens have never really been a problem for the RS40 though, although it is a big issue with the RS50/60. The main problem with lumens on the RS40 is the dimming.

The million dollar question is whether or not JVC has fixed the lamp dimming/failing problems. We won't know that from specs though, but only from seeing how the lamps perform once they're in the hands of customers.

I have no technical expertise in this area but I'm kind of thinking out loud for everyone's take on this but is there any chance that lamps are failing early because the projectors lamps are being driven too hard in high mode? Is it a safe assumption that these models are running in high mode more often and longer because of 3D? If these lamps are being driven too hard or if there is some type of heat issue with these could that be causing these lamps to blow?

Over the last number of years there have been threads on lamps dimming early with the JVCs so the lamp dimming early isn't necessarily something new with the JVCs but maybe 3D has just made things worse. I have an RS2 clone and my projector is for movies only and I have less than 600 hours on mine in about 2.5 years and on my Dalite HP screen all still looks well.

What is the correct way to measure lux or lumens? If one had a meter is it held up to the screen surface and aimed back at the projector?

Yes.

Larry

Time to call JVC for a new bulb. My bulb has dropped so much red it is now un-calibratable.

17 Hours 160.5 LUX
53 Hours 143.1 LUX
198 Hours 108.5 LUX

I have never used 3D and never watched it in high power. I only switched to high power to do these three tests.

I am considering a like new, used RS-40, 7-8 month old, less than 400 hrs, $2-$2.5k price range. Reportedly, the lamp is performing close to what some of the best readings on this thread. After going thru most of this thread, I have become kind of hesitant to pull the trigger with the brightness/lamp dimming issues. What is the current state of affairs regarding this? Are users getting premature lamp failure or dimming with this PJ? Has any statement or any acknowledge/correction come from JVC?

Is the ask price to good to be true or as I think it just probably reflects the market concerns with this unit?

I am embarrassed to say I screwed up my measurement above. I was measuring in a calibrated setting but was using a 5500k setting. When I reset everything back to the same setting my lumens were holding strong.

I just made a measurement at 318 hours with the same setup and meter and came up with 194 for a center peak lux. Not sure how to explain that. That measurement was after several hours of viewing. I can't remember how long I had the projector on for the original measurement, but I am very pleased that the bulb seems to be hanging in there.

It's been a while and I just did a measurement at 578 hours.
Picture mode: Natural
Color space: Standard
Color temperature: 6500K
Gamma: A (somehow I couldn't change this option to Normal this morning, option was greyed out. Had to get ready for work so not enough time to look into it.
Iris: 0 Fully open
Lamp power mode: High
throw 13'2"

116 lux > 454 lumen

same setting but color temperature all the way up to "high bright" (unwatchable)
165 lux > 651 lumen

Wow, quite a difference from when I measured around 50h. Picture looks plenty bright to me, I watch in low lamp mode and aperture at -12...

Picture is getting really dark now, so much that even my wife started to notice.

740 hours.
Picture mode: Natural
Color space: Standard
Color temperature: 6500K
Gamma: A
Iris: 0 Fully open
Lamp power mode: Low
throw 13'2"

38 lux > 150 lumen

Normally I watch with the aperture at -8, but it's getting really dark. Probably I should try getting a new lamp from JVC.

Hi everyone, I did another measurement at 661 hours with the same above calibration and the result is: Lux 167/598 Lumens in normal mode.
I need your expertise to see if the current lumens are acceptable and the drop is normal (10.7% in 200 hrs). the 3D is looking good by the way and no increase in ghosting.

Did you get the 003 flapper lamp?

Not much loss in brightness. Very nice:)

this is V2 replacement lamp, the original lamp popped at 5 hrs

I have the orginal lamp 01 model. I only watch one or two movies a week all at high lamp. So I am currently at 175 hrs. Anybody run 100% at high altitude mode? Will this keep the lamp from dimming prematurely? Or is the 03 model my only hope?

You better get some hours on that lamp so it will die and you can get a new one and do it before your warranty isn't good anymore. My "02" lamp was great in low lamp mode until 500 hours then it dimmed quickly then blew. The "03" lamps with the metal flappers are your only hope.

Mike

At 620 hours I made another measurement. With same "Viewing Mode" settings as above I measured a peak at center of 150 lux. Came out to an 11% drop. So far so good it seems.