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Join Date: Jul 2002
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Below are the results from my Sharp 10K. I did this by hooking up my PC, setting it at 720p and outputting that natively via DVI to the pj. I displayed the 1920x1080 images using William's suggestion of IrfanView at full screen, letting the program do the scaling to 1280x720.
Tip: There are options under the Settings to hide the mouse and remove the file labels from the screen when in full screen mode. William this program was a great call - made it very easy and you can scroll in full screen mode easily between images.
These readings were taken with the AEMC 813 mounted on a tripod 20" from the pj lens. I had velvet around the instrument to reduce settings. However I did not put anything up on the ceiling, and with hindsight after reading the above this really is necessary as there was likely some light reflecting back. I'll retake these measurements someday (total PITA moving my PC to the HT...) but in the meantime this will give us a good starting point as I don't think the results will be much different.
Bulb hours: 80
Meter location: 20" from pj lens
All readings are in lux:
Full white screen: 4499
Ref white square: 4499
Black ref: 2.6
1%: 3.31 | 1359:1
5%: 4.27 | 1054:1
10%: 6.08 | 740:1
15%: 6.73 | 669:1
20%: 7.23 | 622:1
ANSI CR: 279:1
ON/OFF CR: 1730:1
Also I've been working hard to control my room reflections (velvet now on ceiling, dark throw rug on the floor) so I was very interested to see how well my contrast readings were doing at the screen...
Here are the same measurements, except this time the meter was POSITIONED AT THE SCREEN:
Meter location: At the screen
All readings are in lux:
Full white screen: 63.9
Ref white square: 63.5
Black ref: 0.03
1%: 0.04 | 1588:1 (basing these off of 63.5 not 63.9)
5%: 0.06 | 1058:1
10%: 0.09 | 706:1
15%: 0.11 | 577:1
20%: 0.13 | 488:1
ANSI CR: 185:1
ON/OFF CR: 2117:1
Referring back to the measurements taken at the pj (first set listed in this post) its interesting to see DLP maintain its strong advantage in contrast over SXRD and LCoS based on William's posted numbers for the HD2K and the Pearl.
Please let me know what you guys think about these results.
Also are there any conclusions we can draw about how effective my room reflectivity reduction efforts are being, based on the results reported for measurements at the screen?
I'm not sure if there is merit in the following comparison, but what I decided to do was measured AT THE PJ the % drop in CR as I moved from one APL to the next, and compare that to % drop in CR as measured AT THE SCREEN:
Moving from 0 to 1%: 21% drop in CR at pj VS. 25% drop at screen
1% to 5%: 22% drop at pj VS. 33% at screen
5% to 10%: 30% drop at pj VS. 33% at screen
10% to 15%: 10% drop at pj VS. 18% at screen
15% to 20%: 7% drop at pj VS. 15% at screen
I don't think there's much value in the % drop data comparison above in isolation like this. However it would be very interesting to see what OTHER PEOPLE got in their rooms at the screen % drop-wise. I'm thinking that it wouldn't even matter what pj it was or what its CR capabilities were because we're comparing the drop off in CR at the pj % wise vs. at the screen.
For instance if the ratio of someone's % drops at their pj vs. % drop at their screen was better than mine, we could conclude they had better light control, and vice-versa. With enough sample sizes we may even be able to come up with a relative baseline for poorly treated rooms (reflectivity control-wise, average treated rooms, and well treated rooms). People could then compare their results to see how well their room reflectivity control is versus others.
I know we are discussing two different things here. In one case we are talking about the native CR capabilities of the pj itself. And in the other case we're talking about what the user can expect to ACTUALLY EXPERIENCE when watching a movie. Both types of readings have great merit, so I'd like to see us develop this scale (actual experience on the screen) along with the scale being used to measure a pj's capabilities (without the room factored in).