AVS Forum banner

1 - 7 of 7 Posts

·
Premium Member
Joined
·
4,480 Posts
Discussion Starter #1
I own a JVC RS40 that is about one year old and has about 400-500 hours on the latest(003#) bulb. When I turn the projector on the picture is beautiful with what looks to me a combination of ideal contrast, black level, and color saturation. However, after about twenty minutes of watching the color seems to drift to the point where there seems to be a slight loss in the saturation and perhaps a slight color tone that leans towards brown. Seems like contrast is slightly affected too. It's not a super large difference but enough that you eyes detects something is not just right. I am using settings posted by Kris Deering way back when these RS40's were pretty new. As I said, when the lamp is cold the pic looks very good.


Given the nature of the drift to what looks like brown tint is there some color setting changes I can make after it warms up that might bring it back to the way it looks when turned on. I would estimate that this shift is about 5% from cold. Could there be something else that is causing this?


Any suggestions would be appreciated.
 

·
Registered
Joined
·
3,166 Posts

Quote:
Originally Posted by JackB  /t/1420535/color-drifts-after-projector-warms-up-how-do-i-remedy-this#post_22224611


I own a JVC RS40 that is about one year old and has about 400-500 hours on the latest(003#) bulb. When I turn the projector on the picture is beautiful with what looks to me a combination of ideal contrast, black level, and color saturation. However, after about twenty minutes of watching the color seems to drift to the point where there seems to be a slight loss in the saturation and perhaps a slight color tone that leans towards brown. Seems like contrast is slightly affected too. It's not a super large difference but enough that you eyes detects something is not just right. I am using settings posted by Kris Deering way back when these RS40's were pretty new. As I said, when the lamp is cold the pic looks very good.

Given the nature of the drift to what looks like brown tint is there some color setting changes I can make after it warms up that might bring it back to the way it looks when turned on. I would estimate that this shift is about 5% from cold. Could there be something else that is causing this?

Any suggestions would be appreciated.

It's the bulb! I had an RS1 bulb do this too. Only one bulb out of 4 so far has done this. What I did was calibrate it after it was warmed up which was 1 hour. The image was very warm (red) when cold and looked great after the 1 hour on time calibration. It still drove me nuts after a while and I just purchased a new bulb.


You might be able to just calibrate it and it will be fine. You may not even notice the drift after its calibrated.
 

·
Registered
Joined
·
12,404 Posts
this is why calibration after warming up the display helps
 

·
Banned
Joined
·
3,587 Posts
You should be calibrating only after there's about 30 minutes of warm-up on the projector. And you should re-calibrate a projector with UHP lamp as often as you feel like doing it. I'd suggest after every 200-400 hours (this assumes you are doing your own calibration work, of course, not many people would pay a couple hundred to re-cal a projector professionally every 200 hours). Lamps change as they accumulate hours. There's also such a thing as a bad lamp... if it can't be calibrated after it's warmed-up, you may have to replace the lamp.
 

·
Premium Member
Joined
·
4,480 Posts
Discussion Starter #5
The problem is that I don't have any calibration equipment other than the latest Joe Kane disk. Will using that and adjusting contrast and brightness give me the proper calibration you are referring to? Do I also have to use the included blue filters and try to adjust color and hue also. I used the Kris Deering numbers that were done with calibration equipment.


I would contract with my ISF calibrator who did my other two projectors but he wants $700 for the RS40 saying it is very difficult to calibrate.
 

·
Registered
Joined
·
1,055 Posts

Quote:
Originally Posted by JackB  /t/1420535/color-drifts-after-projector-warms-up-how-do-i-remedy-this/0_100#post_22232941


The problem is that I don't have any calibration equipment other than the latest Joe Kane disk. Will using that and adjusting contrast and brightness give me the proper calibration you are referring to? Do I also have to use the included blue filters and try to adjust color and hue also. I used the Kris Deering numbers that were done with calibration equipment.

I would contract with my ISF calibrator who did my other two projectors but he wants $700 for the RS40 saying it is very difficult to calibrate.

Using Kris's numbers are going to be no more accurate than doing it by eye yourself with the JKP disc most likely. Every video component out there has tolerances built into it, and projectors are no exception. They also have bulbs that age and of course adjust the quality of the image as they change. Even with equipment, you could take Kris's numbers and plug them into 20 different RS40s and find one is really close to his, 5 are OK, and 14 are worse than doing it by eye with JKP. Copying settings from one projector to another really just doesn't work, and the screen will cause a color shift as well.


So really, I'd start from scratch with the JKP disc after letting the projector warm up for quite a while. That will get you the best results for your setup without paying for equipment.
 

·
Banned
Joined
·
3,587 Posts
The RS40-50-60 projectors are hard to calibrate, mostly because the gamma controls don't work properly. The remainder of the calibration controls work well enough and you can get some help from the gamma controls without spending a ton of time. Personally, I wouldn't charge more than $400 to calibrate a projector in that series.


JVC projectors vary quite a bit from unit to unit, so copying settings from some other sample of your model is a waste of time. All projectors and panels vary enough that copying settings is usually no better than adjusting by eye without a meter and calibration software. JVC models vary a bit more than average so you can't rely on numbers from any other source.


Do all your adjustments after there are 30 minutes on the lamp and you just have to live with the first 15-30 minutes looking a bit "off" compared to the fully-warmed-up state. That's assuming you don't have a bad lamp... that has happened with some JVC lamps. It's more common, in my experience, for a projector to vary (color-wise and brightness-wise) during warm-up than to NOT vary.
 
1 - 7 of 7 Posts
Top