Projector Reviews

VAVA 4K UHD Laser TV Review- Calibration 1

VAVA 4K UHD Laser TV Review – Calibration Settings: Calibration Notes

Calibration Notes

I recently had a chance to calibrate a new UST (Ultra Short Throw) projector by Vava model VA-LT002. This was my first time working with a Vava so I wanted to spend some time learning the menu and experimenting with different modes and settings. The projector has several modes to choose from but it is limited on the calibration controls. TheVA-LT002 does support HDR but keep in mind that the calibrated SDR settings to not translate to HDR, so I had to use a separate picture mode for HDR. This does require the end user to switch picture modes based on whether they are watching SDR or HDR. A minor inconvenience but it must be done.

The VA-LT002 has two settings for the Laser Mode, High and Standard. This setting is similar to what you would see as a backlight control on an LCD TV or an OLED Light control on an OLED TV. In theory with the Laser Mode on High the projector will output as much light as possible. The downside is a louder fan as the projector is doing what it can to manage heat. The Standard setting makes a dimmer picture but the fan is much quieter. The setting you pick depends on several things such as room design, screen size, screen gain, and desired brightness. When determining the overall light output of a display I use a 100IRE test pattern as a reference when measuring. Once I had the projector dialed in the difference in light output between Standard and High was negligible…40ftL to 43ftL, which is only a 7% difference. The fan does get louder in High mode but only by 3dB to the main seating position…probably not enough to notice once the audio from a movie is playing.

I also noticed in all of the picture modes except the calibrated mode there is a huge color shift in the grayscale when switching between Standard and High mode. Luckily this was not the case in the calibrated mode.

The VA-LT002 has 6 picture modes to choose from: Standard, PC, Movie, Colorful, Sport, and Customized. I measured each mode using a 100IRE test pattern on the factory settings for x, y, and Y with the Laser setting set to Standard and High (note the major change in x,y after switching between Standard and High laser settings). Here are the results (raw data).  For the translation to how many lumens per mode, you’ll find that on the previous page (Performance).:

Standard

High .269, .293, 81.1 cdm2 10882k
Standard .284, .326, 74.6cdm2 8306k

PC

High .269, .292, 81.1cdm2 10882k
Standard .284, .325, 74.7cdm2 8329k

Movie

High .269, .292, 77.7cdm2 10946k
Standard .287, .327, 71.9cdm2 8083k

Colorful

High .269,.292, 81.3cdm2 10946k
Standard .284, .326, 74.5 8306k

Sport

High .269, .292, 81.3 cdm2 10946k
Standard .284, .326, 74.5cdm2 8306k

The last picture mode in the projector is called Customized. This is the mode that I decided to calibrate in as it had all of the necessary controls available to dial the projector in. The out of the box picture preset is Standard which has an excessively blue grayscale and too big of a color gamut when compared to the HD standard rec709.

This shows the grayscale performance before the calibration. The red, green, and blue lines should be as close together and as flat as possible. In this case the grayscale has a heavy blue tint.

After choosing Customized for the picture mode it was time to pick a color temperature to dial in the grayscale. There are 3 presets to choose from: Cool, Warm, and Customized. Customized allows changes to be made while Cool and Warm do not, so the obvious choice was to use Customized. Just a quick note…the Cool and Warm color temperature presets seemed to be reversed. Cool produced a very reddish grayscale while Warm produced a very bluish grayscale.

The Customized color temperature has one set of Red, Green, and Blue controls. I got the best results by using 60IRE as my reference point when dialing in the grayscale. The RGB controls themselves are very granular and allow a very wide range of adjustment. That the controls are more granular, typically means that I can dial in the adjustment very precisely.

After calibrating the grayscale the delta error from 10IRE to 100IRE ranged from 1.9 at 10IRE to 3.9 at 80IRE. This gave an overall average of 2.9. The goal with the delta error is to be under the perceivable difference of 3.0 and the VA-LT002 had an overall average of 2.9 which is very respectable for a projector at this price point.

Notice how much closer the red, green, and blue lines are to each other and how much flatter the lines are. After calibration the grayscale Is much closer to the D65 reference.

The gamma tracked linearly at 2.04. This would be desirable in a room with a considerable amount of ambient light but in the case of a dedicated theater it should be closer to a 2.4. Unfortunately there was no way to adjust gamma as it is fixed to the picture mode that you are watching.

The projector’s gamma tracked in a linear fashion but did not quite hit our target of 2.4. At 2.0 blacks and dark greys are lighter than reference. This can make the picture look washed out in a dark room, but dark details are easier to see if the room is bright.

The color gamut was noticeably too large for SDR rec709 content and the secondary colors (cyan, yellow, magenta) had major hue errors. This causes large delta errors ranging from 4.9 (yellow) to 21.4 (cyan). These errors are large enough to be visible and sometimes extremely obvious. After getting the grayscale dialed in the secondary colors improved greatly but the color gamut was still too big. The projector did not have any color space settings a CMS (Color Management System) so I was not able to make any further adjustments. I was able to manually adjust the main Color and Tint controls but due to the lack of a Blue Only Mode I made these adjustments by eye using some reference test patterns.

Notice the accuracy of white and the primary and secondary colors before and after calibration. White, Yellow, Cyan, and Magenta are much more accurate afterwards.

The geometry and focus were simple to set up. I was able to eliminate most of the edge enhancement by turning the sharpness control down but I was not able to eliminate the overscan. The projector does have picture size options but none of them produced a properly bitmapped image. The 16×9 setting was the closest to correct.