Sharp XV-Z20000 initial impressions and numbers - Page 6

It was fairly significant, maybe 20%. I didn't experience much interactivity. The saturation seemed affected a little. For example, after raising red Value 20% I had to lower the saturation 1 tick.

BTW, I wonder if you even need a colorimeter for this parameter? Couldn't you just measure the light output of a post-calibration white, use that value as a baseline, and then measure the light output of each of the colors?

BTW, I have backed off my changes to the Value parameter. I initially thought it gave the image more punch and vividness. After I lived with it for a few days it started to seem cartoonish and unnatural, so I decided to remeasure. Although the substantial increases to the Value of the primaries had little effect on their saturation, I discovered that it had a profound effect on the color control in the main menu. So I put all Values back to 0.

Why I can't seem to adjust this parameter correctly is a mystery to me, but the image looks (and measures) the best when they are all set to neutral.

That's about right. I find the fan in High mode annoying. In Normal mode it's there but I don't really notice it unless I try.

Yes, I know. I stand by what I said. A few points:

1. One of his criticisms dealt with the artifact he noticed on 1080p inputs. I'm using 1080i inputs, so I didn't see this.

2. Much of his criticism of the Z20000's processing (especially with HD material) seemed to be in comparison to the VXP processing he saw in the $20,000 Marantz 1080p projector, which he thought was a little better. I haven't seen the Marantz, so I can't comment.

3. The Z20000 is the first PJ I've seen that didn't obviously benefit from a Realta-based processor (Vantage-HD) that I have been using for several months. That's fairly high praise. I did quite a bit of A/B comparisons and I've yet to find a single case where I clearly preferred the image I obtained with the Vantage-HD in the loop.

4. I ran the Z20000 through the series of tests provided by the Silicon Optics Benchmark DVD. It passed every test, except one: the race track Film Detail test. To give some much-needed perspective, this is MUCH better performance than what you get with the Lumagen HDQ external processor, which Greg reviewed positively in WSR just a few months ago.

5. Some of these judgments are somewhat subjective. For example, I looked at the bobbing frozen branch scene he mentioned in the Montage of Images and I didn't see the jaggies he referred to. That doesn't mean they aren't there. I just didn't see them.

So, yes, all in all, he and I see this differently. I also think that the Sharp's implementation of gray scale controls is unintuitive and very difficult to use, and he barely mentioned this. People see different things. I guess that's human.

I wanted to post some updated lumens numbers and correct a mistake I made in my original review regarding lens shift.

First, after 422 hours of use, here is my updated lumens chart



As you can see I have lost 20% of the lamp's brightness in the High Brightness iris mode and 35% in all other modes. I can't explain the discrepancy. In my case, the result of this loss of light output has forced me to start using the Bright lamp mode. The Economy lamp mode/Medium Iris mode now returns less than 10 FtL on my 100" 1.3 gain StudioTek screen, but in the Bright lamp mode it is still over 12 FtL.

I made a mistake when discussing the effect of lens shift in my original review. I made 2 assumptions, both of which turned out to be incorrect. I assumed that the 20K would ship with the lens shift at its neutral position as the default AND I assumed that zero lens shift would yield the highest light output.

The result of the first incorrect assumption was that, in my original install with the lens about vertically aligned with the center of the screen, I had to use lens shift to move the image down significantly to fill the screen. This led me to believe that zero lens shift was the lens aligned with the bottom of the screen (shelf mount) or top of the screen (ceiling mount). In fact, zero lens shift is the lens aligned with the center of the screen, exactly the way I had it originally. I was confused about this because the 20K does NOT ship with its lens in the neutral state. Its default is with lens shift invoked for either an inverted ceiling mount (lens aligned with the top of the screen) or a right-side-up shelf mount (lens aligned with the bottom of the screen). Sharp must just assume that these will be the most common installs.

Now, when I moved my shelf mount install down about 15" and noticed measurably higher light output, I attributed this to the fact that I had gotten the PJ closer to the zero lens shift position. I think I even wrote that more improvement was possible if I could only move the PJ lower. As it turns out, this was correct, but for the wrong reason. This leads us to my second mistake.

The best light output for the 20K is NOT zero lens shift. Sharp apparently engineered the optics so that the best light output is just where I originally said it would be: an inverted ceiling mount (lens aligned with the top of the screen) or a right-side-up shelf mount (lens aligned with the bottom of the screen). It's just that the lens shift required to accommodate these installs, though it is the default shift and offers the best performance, it is NOT the zero lens shift position. Zero lens shift (my original install) actually gets you LESS light output. Weird, uh?

I hope that this clears up any confusion my original post may have caused.

The service menu doesn't help, largely because when entering the unit defaults to the high brightness, high lamp mode, which doesn't translate in any obvious way to the mode in which you are likely to use it.

I was able to get a very flat grayscale by using the RGB adjustments under All Colors to adjust the low end and then the RGB controls under White Detail to adjust the high end of the brightness scale. That's really the only way to do it.

Bruno:

First, set the user Color and Tint control using a blue filter and blue color bar provided on Avia or the equivalent. The CMS adjustments in the Advanced menu should allow you to move Red hue either towards magenta or towards yellow. On my unit I had to move red towards yellow. What equipment do you have to measure the color points with?

To pick up on what Greg said, the reason color temperature is not a reliable guide to getting good gray scale tracking is that it ignores green.

Before I did anything, I check more than just one film. Sometimes films have specialized color palette.

Yes, that's fine. Delta-E is a mathematical expression of deviation from a color standard, in this case D65. The lower the Delta-E the better.

OK, I have finally resolved the problem I was having getting the Value parameter right in the CMS.

First, the numbers for the Y of the secondaries I provided in the previous post on this subject were wrong. It really wasn't my fault. I got the numbers directly from ColorFacts, and they had it wrong. Argghh! The intensity of the secondaries is a sum of the intensity of the primaries, not an average. Thanks to Krasmuzik for pointing this out.

Second, you've got to be careful to compare the light output of the color field with an equal intensity white field. So, a 75% color field should be measured against a 75% white field. In Avia, that's the Gray field, not the white field, which is 100 IRE.

Third, if you use a white window, compare that against a color window. Don't compare a white field with a color window or vice-versa.

Here are the updated Rec. 709 (HD) specs.



So you can use a light meter and a white window and color windows to measure the appropriate Value for RGBCYM, which will be a percentage of the measured light output of white.

You'll probably find, as I did, that this parameter (unlike saturation and hue) requires very little adjustment.