- Written by Chris Eberle
- Published on 21 November 2011
The Optoma HD33 3D DLP Projector On The Bench
Equipment used: EyeOne Pro spectrophotometer, CalMAN Professional 3.7 analysis software, Accupel HDG-3000 signal generator, Spears & Munsil Benchmark Blu-ray disc.
All measurements were taken off the screen (Carada Brilliant White, gain 1.4) from the seating position (10 feet back). Video processing tests were performed using an Oppo BDP-93 connected directly to the projector and set to Source Direct mode.
I used the Cinema mode as it provided the best starting point for calibration. All settings were at factory defaults. As I mentioned previously, PureColor was set to 1, which was more accurate than Off. Pre-calibration color measured fairly well with only small deviations from the Rec 709 spec. The only flaw in the luminance chart is green which is quite a bit below the correct level.
The below graph shows the grayscale using the Warm color temp preset and the Standard gamma setting. Even though it runs a bit too warm, tracking is excellent. The gamma shown here would result in grayish blacks and poor overall contrast.
After calibration of the grayscale and gamma, secondary colors line up better with the exception of cyan. I was unable to correct this since the HD33 lacks a CMS. Also, since my pattern generator only sends RGB signals over HDMI, I didn’t have the color and tint controls available.
When the CIE chart is corrected for the Optoma’s actual primaries, yellow and magenta are spot-on. Cyan is still off though. I attribute this to the under-luminance of the green primary.
After literally 10 minutes of adjustment, I achieved the below grayscale and gamma measurements – fantastic! This is amazing performance for a projector that only costs $1499. All I had to do to correct the gamma is set the Standard Offset to -1, one click below default. This quality of grayscale tracking is usually found only in far more expensive displays.
The HD33 doesn’t do much in the way of video processing besides basic scaling and de-interlacing. Only the 24p cadence and the horizontal mixed content clips displayed correctly. This is not a big deal given the plethora of video processing solutions available in many Blu-ray players and AV receivers. The only other significant flaw was a failure to display above-white or below-black information. I tried every combination of settings and was unable to see these signals. I verified with Optoma that this is intentional.
Contrast performance was very good given the HD33’s high light output. Minimum black measured .006fL which is only fair though typical for a DLP. The deepest blacks are found in LCoS and LCD projectors. With a max calibrated level of 29.29fL, the contrast ratio is then 4881:1, which exceeds Optoma’s specification. Screen uniformity was very good with only a very slight green tint towards the right side of the screen in a full-field white pattern. This was not visible in any of the content I watched. The lens is quite good for a projector in this price range. I could see no chromatic aberrations in crosshatch patterns and focus was sharp from edge to edge.