Keohi HDTV - Brand Specific - Panasonic

[BRAND SPECIFIC][PANASONIC]

PT47WX51 Review (First Look) Part 2

Tip from Michael TLV: "Well, I had some time this Saturday before the Atlanta outting to devote to that 47" Panny that I had worked on previously, but did not quite finish with. I set aside the whole day to get to know that bugger more intimately. A surprise of sorts when I arrived at the store. They also had just unpacked the new 56" bigger brother of the 47" unit. It looked interesting and as I was settling down to operate on the 47" unit, I heard a yell for help from the salesman. The 56" OOTB was dreadfully red. A sick purple red ... something obviously went wrong with the transport or the factory calibration. I told the salesman that I would get to it shortly.

I took much time to learn more about the intricacies of the Panasonic service convergence mode and while it looks more elborate than say ... the Toshiba ... I don't think we get nearly as many points to converge and the end result was significantly affected by the lack of more convergence points. Still, it looked more than okay.

Earlier in the week, I got a phone call from a potential customer who was still in the hunting phase ... looking for that special HD set. He happened by Smart Home and saw the 47" in action. (This is the half calibrated unit that I had issues with.) In the course of our conversation, he mentioned that the Panny at the store looked very good indeed and very inticing. The best one he had seen yet ... in any store. I laughed as I told him that the unit was only half done and it still had a number of major issues yet to be addressed. As it was, a set that I could not buy given those short comings. Just a different perspective on things. What I considered to be significant issues, were not at all seen by the unknowing customer.

So things to do this time. I had to see if I could fix the green focus problem that plagued the entire left side of the screen. First up was electronic focus and with a huge sigh ... that did the trick and the green was much better. Mechanical was up next and performed from behind the set. No issues here as the mechanical part was pretty good from the factory.

With the set converged and overscan reduced and image recentered ... I proceeded to tackle the SVM issue again. The firs go around found the plugs in so tight that I could not unplug them. Taking a hint from a fellow tweaker out there that suggested a better way of taking the plugs out, I was able to pop out all three quick enough. Did not have to cut the wires at all. This made a big difference in the image. Taking a big step backwards, I wanted to note something about the physical SVM wires and the apparent corresponding parameters in the Design menu of the TV. When scrolling through the items to parameters 09-76 to 79 ... take all items down to 0F to minimize the effect. It had been surmized that these parameters were SVM items ... but from my observations, they are not. With both SVM and these parameters operating, the TV gives off rather unpleasant edginess. When the SVM is disconnected, the edginess is reduced signifcantly, but it is still there and very apparent. A further reduction of these 4 parameters to 0F minimizes the remaining edginess. These are edge enhancement controls ... and any disabling of the SVM should be done in conjunction with these to fully benefit. Definitely a very satisfying image when both the SVM and the edge enhancement was killed.

Now a couple of notes relating to grayscale adjustments.

The S-video input signal allows for full access to the service menu items.
The 480i component input signal allows full access.
The 480P component input signal does not allow full access. No cuts or Drivers in this mode.

S-video and 480i component share the same grayscale parameters. So I set up the TV based on 480i component this time from the Panny 91 model. Problem is ... the 480P signal was significantly different from the 480i section that the result really ended up diminishing the S-video and 480i sections to get a proper 480P signal. It looks great at 480P, but the image washes out when you go to S-video. The grayscale at S-video and 480I were significantly compromised.

Colour and tint controls and contrast controls in the service mode do not affect 480P section.

Still ... the most important image looked positively stunning at the end. The removal of the protective screen would further improve things. Lens Striping was not required for this particular set as overall uniformity was rather good.

One item that did come up during calibration was the need to reposition the blue screen control to give the service menu values more range. The H-TLV maneuver will work on this set if one wants to try it out.

I'm much happier with the set now that I have had more time with it. Nice indeed although a few nagging issues still remain.

Next up was the 56" set. Essentially the same as the 47" unit ... only bigger. Everything was the same and it calibrated well ... much like the 47". Only difference this time was that I was setting up the TV for 480i. Line doubler worked nicely. Remaining issue with this set was that the upper left quadrant was still blurry after all focusing. A retorquing of the green crt lens would likely be needed at some point in the future. Of course, I was one of the only people that could see that.

The finished 56" sat right next to a Toshiba 65H80 that I had previously calibrated. From looking at the two sets ... it was quite apparent that the colour space triangle of the Panasonic was different from the Toshiba. Panny reds seemed to tend toward a magenta ... while the Toshiba reds were more orange.

The issue with the engineering menu values is meant for the calibrators out there that might read this.