It was suspicious when the JVC product page for the RS4500 only mentioned the infinity:1 dynamic contrast ratio...I'm curious if it is the chips themselves or the fact that they are larger which makes things more difficult to achieve higher ratios.
Based on the screen gain you gave, that is 2,000 lumens at your throw.
Audio/visual lag also seems to be an issue. I had to max out my lipsync delay on my AV processor to account for the added lag introduced by whatever the projector is doing internally. I'll measure this delay today using my Syncheck to ensure that I can compensate for it.
The chips aren't larger, they are a fraction smaller(2K .7", 4K .69") so the pixel size is 4X smaller. My gut feeling is this is the crux of the problem, the number of liquid crystals are reduced due to the smaller pixel size and the inter crystal light bleed to pixel surface ratio increases, thus reducing On/Off contrast.
Actually, you might be right...The CA183 seems to be *under* reading at the screen. Taking the Klein readings off of the screen, and assuming my previous gain calculation of 0.86 is correct, I'm getting ~1900 at the 2.35:1 zoom. I'm getting 12.9 fL on my screen with laser HIGH, iris 0.I'll take some more readings today.Regarding the inifinity:1 contrast - this is nonsense. There is no fade to black, even with laser dimming on. Presumably because the overall contrast is low enough that a jump to black would look far too artificial. The Sony 1000 did a much better job in that regard.I did a quick lightning LUT calibration yesterday and the results were VERY impressive. Some of the best results I've seen for Rec709@D65. Audio/visual lag also seems to be an issue. I had to max out my lipsync delay on my AV processor to account for the added lag introduced by whatever the projector is doing internally. I'll measure this delay today using my Syncheck to ensure that I can compensate for it.
THIS is precisely the root cause of the issue in our opinions as well And I had a chat a while back with Alan Gouger and (if he doesn't my saying so) this is his opinion too... So NAIL... HEAD... HIT IMO in hindsight JVC should have simply made the panel 4 times the size whilst retaining the same pixels size, or even better made the panel 5 times the size with 20% larger pixels size for even better raw contrast performance as compared with the HD panels... Hopefully JVC or at the very least another manufacturer will realize this and do precisely this .
I concur with Arrow's observations. This projector CAN put out a huge amount of noise if room temperature goes up. I've had to reactivate my cooling feed and ensure the room is up to temperature before running the projector to avoid the aircon dumping super heated air into the room and upsetting it. Once the film is running it tends to get lost in the background until the soundtracks goes quiet.Light output is poor - I measure ~1600 lumens @D65 from a 26' throw with iris wide open.BUT, it's also the best image I've seen so far in my room, and the constant brightness light source means no dimming, like bulbs, so I'll probably be keeping it. Need more viewing.
Talking of firmware, I'm on 1.04In 20 years of owning a projector I've never updated the firmware... could this be the first? Seems to be as simple as plugging in a USB stick and going into the 'update firmware' option?Anybody got RS232 working? I'm trying to use standard JVC codes, but with no success...
From what i read here it seems everybody is running 1080P Blu ray on this projector, as it seems its not capable of delivering any usefull lightoutput while maintaining a decent black level for UHD mastered content.. Or am i missing something.?
Yes, this was discussed earlier, when Kris posted about it. My thoughts that I gave on it are what you are thinking, it would not be a smooth transition out of black. It would be jarring, like the LS10500. I also suspect that in the first version, JVC started out, turning the light source off and had full fade to black and after seeing what it did, adjusted the dimming. That is why I assume have infinity listed as the spec. As for why it has not been changed, I do not know. Maybe they are waiting to see what they can do firmware wise?
That says a lot right there ! Considering your last projector was what - a VW1000 ?
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