I will be returning my Best Buy HW10 tomorrow. Tonight I used my PL CA-6x OpticOne Probe to take some light level readings.
Please note the OpticOne is not a sensitive as the CalMAN Chroma-5 I have coming, but it was good enough to present some interesting numbers.
The fixed Projector settings for each of the columns below were:
Black Level OFF
Auto Iris 2
The variable settings were High & Low lamp mode, LOW & USER 4 color temps, and <347> factory CLOSE REG auto Iris setting and my <131> CLOSE REG Auto Iris setting.
This chart reflects light levels produced with 0% and 100% stimulus/IRE full field grayscale patterns. There have been no calibration adjusments made to the projectors grayscale or color tracking.
May I note a couple of things...
All of my <131> CLOSE REG low light settings were stable and the same for low and high lamp modes on the 0% pattern.
The measured brightness for the 0% pattern at the <347> CLOSE REG setting varied between the color temps and HI/LOW lamp modes. In every case, the hi lamp mode was slightly darker than the low lamp mode at 0% and brighter at 100%. This was unexpected and I have no explanation. I invite discussion regarding how the hi lamp mode would produce darker black levels.
The difference between ON/OFF contrast numbers for the <131> and <347> CLOSE REG Auto Iris settings is dramatic. The Chroma-5 probe may well better resolve the lower (0.009).
My technique was to pace the OpricONE probe toward the projector with it's shadow cast in the middle of the screen. I moved the probe as close as I could before the PL CA-6x software stopped rreporting FL readings. I believe it freezes up at a 600 fl value. I backed off so the brightest reading was below 550.
What are my conclusions? I should be careful to assume too much from the OpticOne probe, but the numbers are interesting. If similar readings were to be measured with the Chroma-5 probe and CalMAN software, I can only conclude the HW10 is capable of producing ON/OFF contrast on par with the VW80, which is rated at 60K:1. WE don't really know if the HW10 & VW80 share the same SXRD chip set and some features are just turned OFF, or if the HW10 is a slight derivative with very close ON/OFF contrast performance.
The <347> numbers are very close to those ON/OFF number reported by other folks, who might well improve their ON/OFF contrast with the CLOSE REG tweak.