Optoma HD20 Projector Calibration and Settings
Optoma HD20 Calibration notes: We calibrate each home theater that is reviewed. Our calibration is pretty standard. There's always more that can be done by some of the "hi-end" calibrators. Our calibrations, including the HD20, are normally limited to a grayscale calibration, along with brightness, contrast, color saturation, etc. In almost every case, despite lamp caused variations from projector to projector, our settings will provide you with an improved picture (often dramatically) compared to a projector's out of the box performance.
8/30/09 - Art Feierman
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Optoma HD20 Color Temperature
We used Movie 1 mode as the basis for calibration. Results were then saved in User 1, which was used for all photo sessions unless otherwise noted. We refer to User 1 as Movie 1).
Pre-calibration, the color temperature measurements came out like this:
Cinema:
30 IRE = 6533K
50 IRE (medium gray) = 6525K
80 IRE = 6381K
100 IRE (white) = 6327K
As you can see, all grayscale readings are actually very good, very close to the ideal 6500K, though, overall, just the slightest bit warm (stronger reds - weaker blues).
Unfortunately, the grayscale color temperature doesn't tell everything. Turns out that the third component - green - is well off of where it needs to be. Green is too low, and while that has little effect on the temp reading, it can have significant impact on the actual image. In this case, green isn't off much, but it's enough that what looks like a rather excellent grayscale right out of the box doesn't put an image quite that excellent on the screen.
Optoma HD20 Basic Settings
In addition to calibrating Red Green and Blue for a correct grayscale balance (6500K), there are a number of other settings that come into play. Typically Contrast and Brightness (white balance and black balance), need to be done first. Color saturation and gamma also need adjustment.
Settings for measurements (default values are in parenthesis):
Cinema |
Bright |
Photo |
Reference |
User |
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| Contrast | (46) 45 |
(45) 44 |
(46) 45 |
-46 |
-46 |
| Brightness | (37) 39 |
(39) 38 |
(43) 42 |
(38) 39 |
(38) 39 |
| Color | (58) 46 |
(65) 55 |
-55 |
-45 |
-45 |
| Tint (50) | |||||
| Color Temp | Warm |
Medium |
Cold |
Warm |
Warm |
| Gamma | Film |
Video |
Graphics |
Standard |
Standard |
Lamp Mode = High
ImageAI = Off
All other settings not indicated, are default or off
Optoma HD20 Post Calibration Grayscale: User mode
Post calibration, we ended up with excellent grayscale balance which was evident, when watching the HD20. User mode allows more control than the similar Cinema mode, but when Mike got done calibrating, the two were very, very close. Both are very tight, and stick close to the ideal 6500K.
Color Temp over IRE Range (Post calibration):
User Cinema
20 IRE 6653K 6588K
30 IRE 6583K 6547K
40 IRE 6551K 6623K
50 IRE 6581K 6570K
60 IRE 6522K 6525K
70 IRE 6486K 6473K
80 IRE 6506K 6515K
90 IRE 6503K 6463K
100 IRE 6466K 6432K
Gamma: The gamma for both Cinema and User, overall, measured about the same 2.15 and 2.16. That's only a tad below the ideal 2.2. That said, Cinema starts with the Film gamma, and User, with Standard. The end result is that the gammas, while averaging essentially the same, look a little different. Bright mode uses the Graphics gamma, and has lots of extra punch (helpful with ambient light).
Interestingly, the gamma choices all provide some basic controls - with a gamma curve setting and an offset. I didn't play much with those controls, but they do allow some flexibility, far more than many projectors, that have no adjustments whatsover. At the other extreme, some projectors (Epson brand for one), offer extensive gamma controls. All considered, it's a very nice gamma setup.
RGB Settings
Calibration settings, mode:
User |
Cinema |
Quick Cal - Bright mode |
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| Gain | R = | (0) -5 |
(0) -5 |
0 |
| G = | 0 |
0 |
0 |
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| B = | (0) -3 |
(0) -3 |
(0) -4 |
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| Bias | R = | (-3) -2 |
(-3) -2 |
(-3) |
| G = | (-1) |
(-1) |
(-1) |
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| B = | (-1) |
(-1) |
(-1) |
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| Post Calibration | ||||
| Lumens at 100 IRE: | 701 |
673 |
965 |
Brightest Modes:
Let's talk maximum lumens. As my regular readers know, Mike Rollett took over doing all our projector calibrations a year and a half ago. We tend to see differently when it comes to setting up the "brightest" mode. Mike tends to try to maintain brightness, while making the picture a little better color wise. I, on the other hand, try to get out the maximum brightness, without the image quality suffering too much. My assumption is that you are using Bright mode (in this case) when you are fighting too much ambient light.
As a result, with this Optoma projector, Mike's "quick-cal" settings are not as bright as we would get if I had tweaked the Bright mode. Because we are both compromising image quality (but to different degrees), we don't have a way to consistently measure all projectors' Bright modes the same (other than by calibrating them for best possible picture, which ususally ends up with brightness pretty much the same as the "best" mode).