Posted on December 20, 2019 By Phil Jones
JVC DLA-NX7 Home Theater 4K Projector Review – Calibration Settings: Calibration Notes, Best Mode SDR Calibration, Best Mode HDR Calibration
I performed two calibrations on the JVC NX7 (Best SDR Mode & Best HDR Mode) which can be saved in two of the projector’s user presets. The JVC NX7 is equipped with a color filter which expands the projector’s color gamut to nearly 100% of DCI-P3 but it reduces the projector’s brightness output by about 10%. When Natural or one of the customizable USER modes is selected the default for the color filter is OFF. Since SDR content which is limited to REC.709 color space, I chose the color disengaged for the SDR calibration because additional brightness is more beneficial than having access to a wider color gamut. When viewing HDR content, if you switch the COLOR PROFILE to BT2020 the color filter will be engaged, while if you select HDR the color filter will be removed.
The NATURAL picture mode was the most accurate out of the box when viewing SDR content (D65 color temp with Rec. 709 color space). Since the USER 1-6 picture presets settings are identical to the NATURAL mode, so I chose USER 1 as the basis for the best SDR calibration. I also set the LAMP POWER to Low to reduce noise and maximize bulb life. Prior to calibration, the DeltaE measurements were between 2 to 6.
I increased the CONTRAST from 0 to 8 which clips whites just above 235. I left SHARPNESS along with COLOR and TINT at their defaults.
Since this projector’s strong suit is black level and it would probably be utilized in a darker room with light control, I set my SDR target gamma at 2.4. The default gamma for the USER 1 mode was 2.2. Under the GAMMA menu, I selected to CUSTOM 1 with a CORRECTION VALUE of 2.4. which got me closer to my target of 2.4 (or BT.1886).
The JVC-NX7 offers several additional Gamma adjustments including PICTURE TONE, DARK LEVEL, and BRIGHT LEVEL for each color (WRGB) which I used to further fine tune the projector’s gamma performance.
Under the WHITE COLOR SELECTION, I set the PICTURE TONE to -5. Under the BLUE COLOR SELECTION, I set the PICTURE TONE to -3, the DARK LEVEL to 2 and the BRIGHT LEVEL to -1. For SDR content, I set the COLOR PROFILE to BT.709. The COLOR TEMP pre-set was 6500K which measured an 7500K average (plus blue / minus red). I made some adjustments to the RED, GREEN, and BLUE GAIN to reduce grayscale to a 6500K average.The JVC NX7 has a traditional 2-point white balance adjustment. It also offers the ability to make fine grayscale adjustments using the COLOR SELECTION, PICTURE TONE, DARK LEVEL and BRIGHT LEVEL adjustment located under the GAMMA menu.
Measurements taken at mid-zoom with lamp power set to low. The average Gamma pre-calibration: 2.2 (target 2.4) Average Gamma post-calibration: 2.42 @ 1118 Lumens.
White Balance calibration settings for Night mode.
Post-calibration white balance was very good with a 6500K average. The average DeltaEs for grayscale and color were less than 2, with the majority of measurements being under 1. During calibration I set APERTURE (Dynamic Contrast) to manual but after I turned it to AUTO 1 to improve dark scene black levels. After calibration, the projector’s brightness output was 1118 lumens which produced about 17ftL on my 120” screen.
For my Best HDR Mode calibration I chose the USER 2 mode as the base. The Pre-calibrated HDR white balance had a heavy blue cast pushing the white balance into the 7500K range. DeltaE numbers ranged from near 6 on the bright end down to 2 at the low end.
I had to reduce the green and blue gain to bring the WB back down to a 6500K average. I left Sharpness along with Color and Tint at their defaults.
The JVC-NX7 did a good job tracking the HDR EOTF right out of the box. I never recommend adjusting a projector to perfectly track the ETOF because it normally results in an overly dark picture. Once the White Balance and Color tracking is accurate, EOTF should be adjusted via tone mapping to optimize the HDR material being played. In other word’s 10,000 nit content will require a different HDR tone mapping than 1000 nit material.
The JVC NX7 is one for few projectors equipped with an Auto Tone Mapping feature which does an excellent job balancing average screen brightness with the need to maintain highlight detail. Not only can NX7 use the content embedded HDR Metadata (MaxFLL and MaxCLL) to make tone mapping adjustments, it can now measure HDR10 content dynamically (Frame by Frame or Scene by Scene). Based on content’s metadata or its own readings, the NX7 can automatically optimize its HDR performance based on the content (10,000 nit, 4000nit, 1000 nit, etc).
Note: The Auto Tone Mapping feature is configured based on a 100” screen with a 1.0 gain in total darkness. If your screen’s size/ gain or room environment is different, you can adjust the projector’s tone mapping baseline using the Mapping Level adjustment.
Since the JVC NX7 can auto tone map, I left the Brightness and Contrast at their default settings. The HDR10 Picture Tone setting can be used to manually adjust HDR EOTF tracking. Increasing the setting, raises screen brightness but clips more highlights. Lowering the setting maximizes highlight detail at the expense of overall screen brightness.
There is also an HDR Dark-Level and High-Level adjustments which can be used to finetune the curve (roll off) of the dark and bright areas in HDR10 material.
Brightness at Mid zoom with LAMP POWER set to High was 1513 Lumens.
Overall, I was very pleased with the 4K/HDR white balance and EOTF performance after calibration. Final lumen output after HDR calibration measured 1523 (in high lamp power mode with color filter engaged).
© 2019 Projector Reviews (V0625)