Here's a quote from Chad's review, including the calibration issues. On the other hand, D-Nice stated he had fewer issues calibrating a VT30. In any case, the firmware upgrade should make it easier to calibrate.
The review unit was a bit green, though Chris had it running the break in DVD for about 35 hours before I arrived. Having downloaded the latest version of CalMAN, I got the TV interfaced with my laptop and calibration gear to check out the automatic calibration feature. Unfortunately, at this stage of it's development, the feature proved to be useless for the most part. It did open up a new picture preset called ISF Day (Night would also be available), but unfortunately the 10 point white balance and grayscale adjustment was not available to select; only the 2 point white balance adjustment was available. Also, far too many necessary picture options and adjustments were grayed out, making even a 2 point calibration far from optimal. However, I did have it try the automatic calibration. What I ended up with was an ISF Day mode with a peak light output of only about 28 fL and a pretty good white balance, but poor performance in other aspects of the picture.
I did a lot of experimentation in Custom mode, since it has a fantastic variety of adjustments in the advanced user menu. Unfortunately, some of those controls just did not work. Most of the CMS adjustments were non functional, though I was able to adjust the luminance (out of luminance, hue, and saturation) of each color. Even with the luminance adjustment, however, things were not as they should be. Setting the color at one video level resulted in color compression at other levels. I tried to minimize the effect with different combinations of the master color control and the luminance adjustments, but could not entirely eliminate it. I also experimented with different panel brightness settings, which has had an impact on color linearity in past Panasonic models, with no success. I concluded that the color was going to be compromised in Custom mode, but I continued on in the hope that other aspects of performance might make up for it.
The gamma adjustment in Custom mode did have a 10 point detail adjustment. However, after a while of experimenting, I found I really was not making the improvements I had hoped for. It was like trying to climb up a slippery slope; I seemed to make a couple step of progress here and there, but soon found myself not far from where I started.
The VT30's ABL (auto brightness limiter) was fairly aggressive, allowing very small white objects to be bright enough, but severely limiting larger bright objects. All plasmas have this to a certain degree to limit power consumption and protect the panel, though less ABL interference results in a better image. I found a new adjustment for video type in the VT30's menu that did seem to make the ABL less obtrusive when set to photo or video (default was off), with no apparent disadvantage. It did increase blue in the white balance by a tiny bit, but not enough to be visible.
I found Cinema and THX modes to be the best starting points for calibration. Cinema mode had slightly better gamma, but it's light output was more limited than THX. For moderate ambient lighting conditions, THX seemed the best choice, though Cinema may be slightly better for a totally dark room. Because of it's slightly better versatility, I concentrated my efforts on THX mode.
As with some past Panasonic plasmas starting with the V10, supplying a 1080P/24 signal and engaging the 96 Hz mode resulted in subtle measured changes to the picture relative to 60 Hz mode. 96 Hz mode reduced light output very slightly, degraded the gamma a bit, and reduced blue in the white balance by a few percent. All of these changes were very subtle, and are not cause for too much concern. Also like the V10, engaging 96 Hz mode did have a positive impact on what might be thought to be an unrelated but important picture aspect: black level and contrast. While the VT30's black level was too low for my meter to read reliably even in 60 Hz mode, I could see a slight improvement or darkening of the black level when engaging 96 Hz. 96 Hz mode did introduce a tiny bit of flickering in some test patterns, but it was so slight and infrequent that it did not bother me at all with video.
I found that all of THX mode's user menu picture controls were pretty close to optimal, though I did raise contrast and lower sharpness both by a small amount. The biggest improvement in THX mode came from adjustment of the grayscale in the service menu.
Maximum light output after calibration in THX mode was about 38 fL with my usual small (10%) test windows. That is adequate for a light controlled room, but on the low side for most living rooms. With larger measurement windows, the white balance shifted slightly (reducing green along with other changes) and light output reduced to 35 fL with 18% medium windows and 32 fL with 25% large windows. With a 100% full field, maximum light output dropped to just over 12 fL.
After all the technical tests were complete, I put my familiar demo material in the Blu Ray player and sat back to enjoy the picture.
Pans and motion were surprisingly good, even with the VT30 in 60Hz mode. I was impressed with the lifelikeness of the image. However, colors lacked a tiny bit of richness; skin tones were natural but a bit too polite. There was a good but not quite excellent sense of depth, and shadow detail was strong and neutral toned. Try as I might, I saw no traces of DSE (dirty screen effect), contouring, or fluctuating black bars. There was very good pop in a dark room, though the picture was not terribly exciting with moderate lighting. Overall, I thought the image was very good, though a little lacking in "Wow!" factor. Looking back through my notes and calibration data, I believe the blame for the lack of excitement can be laid at the feet of the not fully developed calibration adjustments. With black level and contrast this good, the image should be oozing with pop and excitement. However, the lower than optimal gamma, slightly uneven color luminance with red being low, and tame light output seemed to combine to rob the image of some of it's edge. These are all things that could be eliminated if only the VT30's calibration flaws could be corrected. In fact, Custom mode appeared to bring a substantial boost in excitement and verve to the table at the expense of color and overall picture accuracy. If Custom mode's (or the auto-calibration ISF mode's) calibration flaws are corrected with a firmware update, we'll have a TV to really cheer about. As it is, I felt it was very good, but not living up to it's full potential.