Re: JVC RS40 3D PJ

[Anonymous]

@Doug Blackburn 3148 wrote:

I haven’t worked on a “40” but have spent a lot of time with the 50/60 (have a 60 here now). So this applies to the 50/60… not sure if it also applies to the 40.

There is a problem with 3D mode that causes “electric” reds and oranges that don’t appear in grayscale or CMS measurements. If you view content after the calibration that doesn’t have the right shades of red or orange so that you can SEE the problem, you could easily miss it. It might be fixable with an adjustment (and measurements) at 95% stimulus, but you may not be able to fix it with the controls in the 50/60. To get around the problem, I used Cinema mode for 3D, setting it to High lamp mode. High lamp mode is absolutely needed for the 50/60 in 3D mode… with a brand new lamp you may think 3D is bright enough that High is not needed, but after the lamp gets to 300-400 hours, you DEFINITELY begin to feel like 3D is too dark in Normal lamp mode. You may or may not need High lamp with the 40… the 40 makes more light than the 50/60 by quite a bit.

I think the lesson here is to measure 20 or 21 points when you think you are done to make sure you haven’t missed a narrow-band problem that is EASILY visible in the final images. I’ve already seen another RS60 that was calibrated (by someone else) for 3D using 3D mode and it had the SAME “electric” red & orange problem mine had (firmware is 1.5 I think) for 3D content. This shows up really well in some of the costumes in the 3D Cirque du Soleil disc that came out recently. Properly calibrated, the “electric” reds and oranges appear “normal” which is bright in these costumes, but not so bright that they appear impossible without their own power source!

Thanks for the input Doug.

I calibrated a 40 today. Got decent gamma tracking by using Gregg’s method of using gains for the 100% and custom gamma for the rest. Set gamma using the 50,60,50,40,50,60,40 etc… method, then corrected greyscale and touched up gamma. This way there is not major issues with gamma tracking. I did notice that at 25% there was a spike of red that was visible and the meter was seeing it as well. However, since there is no way to adjust 25% I left it at that. I got about 14ft/L with normal lamp settings on a 110in screen.

For 3D, using 3D mode, and high lamp I got about 3ft/L (thru the glasses). Post calibration I got about 2 ft/L. No 10point gamma in 3D so the low end was clearly red tinted below 30%, from 30-100% it was pretty decent. Still, it looked good. Not sure how long though, since its so dim.