CurtPalme.com Home Theater Forum

THX-UltraII · Joined: 21 May 2012 Posts: 22

Guys,

I just bought a Sony VPL-VW1000 projector. The first thing I always do when I calibrate my projector is make sure the contrast and brightness are set correctly. I always do this by putting up a black clipping test pattern for the brightness and white clipping pattern for the contrast (from the AVS709 disc). I first adjust the brightness and after that the contrast.

For the contrast I raise the contrast level to the point where I can still see 230-234 flash. But I just got a reply in the official VW1000 topic that changing the contrast does not only affect the bright parts of the greyscale but also affects the individual color channels. From what I ve been told the individual color channels will clip BEFORE the white will clip. So am I correct that I need to check the color clipping FIRST and only AFTER that look if the white does not clip?

If I m right with the above, HOW do I exactly check the color clipping (with the AVS709 dics)?

HogPilot

THX-UltraII · Joined: 21 May 2012 Posts: 22

So theoretically when I increase the LOWEND red green AND blue with the same amount all I do is lowering the overall BRIGHTNESS?

Let me explain what I EXACTLY do when I calibrate my projector so you can tell me if this is the right way. I use Chromapure with a calibrated i1 Display Pro III meter:

1. setting the brightness.
I do this with a black clipping pattern from the AVS709 disc. I set the brightness value to a point where I can still see bars 17-25 flash (although 17 and 18 are pretty hard to see flashing from seating distance)

2. setting the contrast.
I do this with a black clipping pattern from the AVS709 dics, I set the contrast value to a point where I can still see bars 203-234 flash (although 234 is pretty hard to see flashing from seating distance)

3. setting the greyscale.
I take Custom3 on the VW1000 as a starting point which is basically D65 which you can adjust. I put up a 80IRE pattern and adjust the Highend R and B values until R, G and B all show approx 100% in the Chromapure software. After this I put up a 30IRE pattern and adjust the Lowend R and B values until R, G and B all show approx 100%. After this I go back and forth between 80 and 30IRE untill I get a perfect respons from both. After this is ok I check 10-100IRE and I look for room for improvement. 30-100IRE is ofter already perfect then but 10 and 20IRE are hard sometimes a the Lowend R and G might get a few notches to get it better.

4. setting the gamma.
I aim for 2.3 gamma because I have a pitch black HT room. The 2.4 gamma on the VW1000 seems to give me a pretty good almost flat gamma curve.

5. setting the color and hue.
I adjust the color and hue values of the VW1000 to get a color gamut as good as possible.

6. setting the sharpness.
Nothing important to say about this. Just look close and good

7. re-check
After all of this I check again from point 1 to 5 to see if there are any small adjustments that need to be made.

I would like to know if this is the right way or if I m missing something. I ask this because the reference setting of the VW1000 puts the CONTRAST setting on MAX (100). With this value my white clipping pattern DOES NOT CLIP but a VW1000 user on the AVS forum told me that his calibration guy lowered the contrast level to 93 because with the max setting (100) there where other things that did not look so good. Maybe it is the color clipping which is not good with setting the contrast to 100.........

HogPilot · Posted: Thu Oct 24, 2013 12:32 pm Post subject:

ChrisWiggles · Posted: Sat Apr 19, 2014 6:48 pm Post subject:

Step 7 is always critical. Calibration is an iterative process, so you always want to go through everything again and check for latter adjustments that may have affected/interacted your first go-round.

Particularly if you have to adjust greyscale a bunch, that can/will definitely affect your clipping point, so always good to go back and check for that. And you're right that you want to look for clipping OR colorshifting when setting the white point (contrast control), and be below that point. Whether you want to align the clipping/colorshifting point to reference white or peak white, or somewhere in between is a subjective decision.