JVC RS40/X3 Calibration Thread - Page 8

The Eye-one LT is generally considered the best buy for a low cost (ie., $150 price range) colorimeter. The HCFR Software is freeware and is widely used with the various Eye-one models. For a step up if you purchase the Chromapure software you can have them calibrate your Eye-one LT (for a fee). For some more $$ you can go with a calibrated Chroma 5 along with the Chromapure software.

See Post #1 of this thread for links to the calibration for dummies guide and info for downloading and burning the AVS HD Calibration Disc.

1. Since the RS40 does not have a color management system (CMS) for calibratiing the color points, then you should use the combination of presets that get to as close to Rec. 709 color points as possible. The "standard" Color Space setting is intended to be close to Rec. 709 and using this in combination with the "natural" Picture Mode (some people may prefer to use "film" Picture Mode instead) should get you close to the correct color points. However, if you also using an external video processor (such as the Lumagen 3Dmini) that has full CMS controls, then perhaps setting the RS40 for one of the wider color spaces will allow for better color space calibration via the external processor.

2. You can leave the Black Level set to the default of 0 to start with. If you cannot get the reference black level calibration correct (ref. black = video level 16) using the brightness adjustment, then you can use the Black Level control to fine tune the black level.

3. Any of the 3 settings for HDMI input mode can be made to work, as long as you calibrate the black and white levels for that mode. However, the "standard" setting means that black-than-black (video levels 0 to 15) and whiter-than-white (video level 236 to 255) are not passed nor displayed. Using the "enhanced" setting makes it the easiest to calibrate white and black levels using a test disc as all video levels 0-255 are passed. While the "super white" setting passes video levels 16-255. Some people like to calibrate to pass some of the whiter-than-white video (above video level 235) and either the "enhanced" or "super white" setting will support this.

The freeware AVS HD Calibration disc (see link in Post #1 of this thread) can be downloaded and it is an ISO file (intended for burning to a DVD but intended to the played on a Blu-ray player). Overall I've found that its set of HD calibration patterns are as good, or better, than those on the commerical HD calibration discs (e.g, Digital Video Essentials).

I've added a new Post #2 to this thread to provide calibration tips for the RS40. If you have additional calibration tips or suggested corrections or additions to what I have already posted please send me a PM.

As a starting point for your measurements try setting your projector's lens aperature (iris) fully open (setting of zero), lamp power to "high", the color space to "standard", the Picture Mode to "natural". and gamma to "normal". Next use the AVS HD Calibration disc to set the reference black and especially white levels. For max. lumens of output from the projector the white level should be set, using the projector's constrast control, so that on the the AVS test pattern with the flashing bars the one marked 235 can be seen flashing but very few (or even none) of the higher value bars (i.e. values 236 thru 255) are still flashing. Once you have calibrated the projector for reference white level (as described above), then display the 100% white full screen test pattern from the AVS disc. The lux meter has several ranges it can be set to and for your case the correct range will probably be the 0 to 2000 lux range. Place the lux meter sensor directly in front of the screen with the side of the sensor with the white dome pointed back toward the projector. For a peak lumens measurement place the sensor just in front of the center and the screen and measure the lux. For ANSI lumens you will need to make 9 measurements by imagining the screen divided up into a 3 x 3 grid and then taking a lux measurement at the center of each of the 9 rectangles that make up the grid. I have attached a zip file that contains an Excel spreadsheet that will do the conversion from your lux readings into the projector's lumens. You will need to enter your screen size at the top of the spreadsheet, then enter the lux value(s) that you have measured. Also when you report your results be certain to let us know both your screen size the your projector-to-screen throw distance.

 

Lux to Lumens Calc.zip 3.380859375k . file

For your zoomed CIH 2.35 AR mode, in the spreadsheet set the AR to 1.78 then for the screen size entry you would be entering the actual diagonal image size (i.e., including the overscanned part of the 1.78 image that falls off of the actual screen). You can do this by entering a diagonal size that produces a calculated screen width value in the spreadsheet that matches the actual width of your screen. You may also want to measure the the lumens with it zoom out to an actual 1.78 image. The results (in lumens) should not be the identical since the 'f' stop of the lens changes as you zoom and thus the light loss thru the lens should be a little more when zoomed to produce a smaller projected image.