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WS-55805 Calibration

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Tip from Mr Bob:  "Mit 55805: EXCELLENT TV!  Couldn't find one reason to have to pass on buying this unit.

The blue electronic defocussing was absolutely no problem. Focused up as sharp as any I've done in the last 5 years, with no flaky blue outlining of white lettering/characters. 

I don't use a mirror, BTW, for the electronic focus--on this unit that is not necesary, as the image can be fully seen up close and personal, while tweaking the focus block, which is right down in front, practically in your right hand. You're so close to the screen you could lick it. 

For the mechanical focussing, I still don't use a mirror. I desecure the screen -- pull the screws at the bottom -- and hinging it at the top, I observe the image as I pull the screen out and then back in a couple of times; then at its fully flattened position, I push it in a little further with a dry cloth, just to see what that inner limit tells me. When you have adjusted the focus perfectly and it is completely tight, the image will show you its scan lines perfectly from an inch out at the center, as you draw the screen out from the mirror, to 1/2" in from the plane it normally rests at (more, up to a full inch inwards, if your screen will give any more than that), from being pressed on with the dry towel. All thru that stretch of distance from the mirror, in and out, the scan lines will be in perfect focus if the focus is set correctly.

If it loses it on its way OUT from center, as you swing it on its hinge at the top, within half an inch--starts to go out of focus--but then keeps it, on the other hand, for as far IN as you can safely push it with your dry cloth--then I know it's not completely centered yet, distance-from-mirror-wise. (Which is of course the definition of mechanical focus...) That means it's more in focus closer to the mirror than farther away, and thus the focus is not centered exactly at the distance point where the screen will sit when being watched. It's center point of focus is in towards the mirror an inch or so, say, rather than right at the precise distance where the screen sits while secured and being watched. 

Doing it this way, rather than using a mirror, allows me to view the image from about 10 inches away, rather than from several feet away. Can't exactly lick it in this case, but you're still so close you could breathe on it ... Makes for some VERY exact focusing...

The tuner was excellent. No dot crawl--ie, excellent comb filter--and was markedly cleaner and sharper on the cable channels his area has, than the Digital Cable converter box provided by TCI. With this unit you can split-screen the two--the internal tuner vs. the piped-in cable box signal, delivered thru composite inputs--and see the difference in real time. The difference in tuners was truly striking, with the digital cable box losing by a country mile.

(For Mr Bob's thoughts on composite and Svideo, go to list of Tips by Mr Bob)

We didn't have a chance to examine the possible Y/C delay problems Paul so eloquently showed us all how to remedy--time grew short real fast, and all of a sudden the owner had a black tie dinner he and his wife were expected at. Having put in 2 separate 4 hour sessions, I still just barely had time to wrap up and complete the job, for him to be there on time. Thus we didn't have a chance to just sit there and watch something, like I would have liked.

But the cable was hooked up thru the S-Video patchcords, and looking at it, I saw absolutely no evidence of the Y/C delay Paul found on his. I am well aware of what to look for, as I sent back 2 Sima Copymasters earlier this year because of horrendous Y/C delay problems--half an inch of red to the left, on white peaks! And this was only present on S, whereas composite thru that Sima copyguard filter looked great. 

No evidence of that phenom here--obviously they did their homework on this unit, during the factory setup. None on the DTV inputs, either.

The only thing the owner is still worried about is the screen burn issue. We tried Matrix out, and he was dismayed that there is no way to eliminate the black--not gray--bars at the bottom and top.

At first he thought that something was wrong, but I explained to him that HDTV is 9x16, while Matrix -- and Fifth Element, and probably a host of other new classics -- is 2.35 : 1. Which of course is longer width than 9x16--really stretched out in comparison--leaving space at the top and bottom.

This unit does not provide gray bars in this instance, while it does in other modes--Mit calls them "formats". But then again, I don't know if I've seen a RPTV that does provide this if the movie is filmed in a longer aspect ratio than 9x16. 

All in all the picture on this unit was superb, and every bit the equal of any other HDTV picture I've seen yet, including the 2 $5,000 Sony 34" direct-views I calibrated within the last few weeks. The line doubler was not ostentatious, and I barely knew it was there. The colors were rich andreal, and I didn't have to change the grayscale much at all, tho the original pic did have just a little too much of that old Mit "hunter green" in it. But that's just me, possibly--not many people would have noticed it, as it was only really apparent on B/W movies I would run across while tweaking. In regular color it was almost unnoticeable.

I liked this unit, and would have no problem owning one, as long as I could control myself and keep the Contrast down on letterboxed movies...

Convergence Notes

I tweaked the user 64 point real good, letting go of my attachment to getting the geometry perfect on this visit -- it's pretty good right now, I must say, just off center a bit, very little bowing ...

The mechanical focus was dead on, no improvement there needed, I can tell you that much. Most new out-of-the-box Toshibas need this right off, usually on 2 out of their 3 lenses.

The grayscale was nearly perfect, and I would have preferred to get into the service mode rather than futz with the mechanical screen controls, but the extra green evident in the darks was so minute that I could safely tweak the green screen control just a touch, which took care of that. 

Those screen controls are self-limiting on that model -- and probably all models of this generation, I could see that in the action as I turned the control -- and you don't want to be towing them off-center too much, or you'll affect things that are factory set, and that you really don't want to be messing with unless you want to be talking to the factory, explaining why you have to be talking to them at all ... If I hadn't been able to effect this change without really turning that control a lot, I would have set it back to where it was, and waited for the codes.

If you get one of these Mit's where the geometry is already dead on, you can do the red and blue convergence yourself, without having to get into the service menu, as the red and blue 64 point is available to the viewer, under the Advanced Settings menu. The adjustments range that will be memorized is limited compared to the range memorizable in the service mode, but if not that much adjustment is needed, you can dial it in yourself just fine.

More on Mechanical Focus

All 3 were dead on, as seems always the case on Sonys, and rarely the case on Toshibas, which usually need refocussing mechanically on 2 out of the 3 lens turrets, out of the box. 

On the other hand, Toshibas are usually more dead on than Mit's on nailing D6500K, out of the box. This 55805 needed just a bit of alteration -- just a bit too much "hunter green" in the darks -- but all in all, this probably would not have been noticeable to 95% of the population."