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Don't dump your CRT RPTV! - Page 243

post #7261 of 12297
Quote:
Originally Posted by Mr Bob View Post

All displays need some level of overscan, as not all channels out there are identical to each other in size and placement. With 0% overscan, many of them would show edges where we really don't want to see them. So having a modicum of overscan is absolutely necessary, even on the big ceiling projectors, where 0% overscan is imminently doable, even on CRT.

My 73" hovers right around 2.5-3% with all the shimming and overscan redux that I have fine tuned into it. I would not want it any less than that.

b

If I set my front projector to 0% overscan the top portion of the screen, two pixels going all the way across, while watching tv. shows as if there is noise or some interference going on on top. What this really is, is the data for the close caption. So if you don't want it to show, you have to use some overscan to get rid of it.
post #7262 of 12297
Thread Starter 
I rest my case! 2% would be the lowest I would want to go, in any projection setup.



b
post #7263 of 12297
Quote:
Originally Posted by Mr Bob View Post

Yeah, but be sure to take credit for all the work you put into it, getting it there!



b

Well...yeah...

Quote:
Originally Posted by superleo View Post




I'm sure he doesn't, but with the size of his tv and the PQ plus some HD material such as this...






Damn skippy it is!

Quote:
Originally Posted by Mr Bob View Post

Nice pic, Leo!
b

Quote:
Originally Posted by Mr Bob View Post

I rest my case! 2% would be the lowest I would want to go, in any projection setup.



b

I agree 100% (the 100% not to be confused with the 2% overscan figure!)
post #7264 of 12297
Quote:
Originally Posted by Mr Bob View Post

Yeah, but be sure to take credit for all the work you put into it, getting it there!



b

Well...yeah...

Quote:
Originally Posted by superleo View Post




I'm sure he doesn't, but with the size of his tv and the PQ plus some HD material such as this...






Quote:
Originally Posted by Mr Bob View Post

Nice pic, Leo!
b

Damn skippy it is!

Quote:
Originally Posted by Mr Bob View Post

I rest my case! 2% would be the lowest I would want to go, in any projection setup.



b

I agree 100% (the 100% not to be confused with the 2% overscan figure!)
post #7265 of 12297
Lens flare is my only concern at this point. Back in 2003, I had a pro, Micheal from western canada, an asian fella, come by and calibrate the tv, too bad we never addressed the flare issue at that time, actually more surprised that he never spent a little time trying to fix it. I heard about using tape to try to remedy it. In the FOTR when Gandalf walks into the cave and lights his staff, there is major haloing. Anything I can do Bob?

Nice pic of silicon sally fellas.
post #7266 of 12297
Quote:
Originally Posted by tubeheadEL34 View Post

... In the FOTR when Gandalf walks into the cave and lights his staff, there is major haloing. Anything I can do Bob?

I'm sure Master Bob will get you his take on this one, but haloing usually indicates dirty optics.

If you haven't clean your optics over a year, it wouldn't hurt to do some cleaning.
post #7267 of 12297
Thread Starter 
Rigjht. And internal reflections. Some brands are worse than others about making sure the optical cavity remains flat, non-reflective black, like the inside of a classic bellows/accordion camera. Which is lined in black felt, specifically applied there for internal reflection dampening and neutralization.

Hitachi and Pioneer are 2 of the worst offenders. Both brands leave lots of bare metal exposed. What brand is yours?

I was just inside a Mit HDready set of lenses because of penetration of the cleaning liquid, and not only was the deepest most lens all glass, but one of the plastic lenses was coated on one side!

But usually there is no coating, so you also have lots of internal reflection between lenses, and there are 4 lenses per lens barrel. 24 surfaces, most of them totally uncoated. Nobody coats all their lenses in there like they should, that I know of. It would be too costly, but might eliminate lens flare completely, if the optical cavity has also been lined with black felt. (Duvetyne is good for movie theaters, but only goes so far with CRT RPTVs...)


b
post #7268 of 12297
Here's a little something you don't know about me Bob...YEARS ago, (decades actually, early-mid 80's) I used to work for a company called US Precision Lens where I made, (have you guessed yet?) the lenses for large screen TVs.

They start off as a block of plastic then are ground down to the dimensions specified and then sent off to the polishing department. Was a boring job but I made so many lenses...and there were about 6 others doing the same thing as I was so one can imagine the number of lenses produced. Took about 5-10 minutes per lens to lathe down. It was interesting to see the process from beginning to end. They even had test sets setup and we got to see the lenses in action.
post #7269 of 12297
RE Lens Flare

My TV is the hitachi 51f500. I lined it with the black felt a few years ago, but it did not reduce the lens flare when the picture has a bright object against a dark background. I also clean the optics every year but this set has had this problem since day one. It is not major, but something you are aware of when you know where to look. I've read threads where crt owners talk about "lens striping" to take care of this widely reported problem.

Are you guys saying that your sets don't have this problem?
post #7270 of 12297
Turn the brightness/contrast down. This is classic of a set being left in 'torch' mode.
post #7271 of 12297
Thread Starter 
Quote:
Originally Posted by Splicer010 View Post

Here's a little something you don't know about me Bob...YEARS ago, (decades actually, early-mid 80's) I used to work for a company called US Precision Lens where I made, (have you guessed yet?) the lenses for large screen TVs.

They start off as a block of plastic then are ground down to the dimensions specified and then sent off to the polishing department. Was a boring job but I made so many lenses...and there were about 6 others doing the same thing as I was so one can imagine the number of lenses produced. Took about 5-10 minutes per lens to lathe down. It was interesting to see the process from beginning to end. They even had test sets setup and we got to see the lenses in action.

Nice stuff! I have seen your lenses in lots of high end projectors.



b
post #7272 of 12297
Thread Starter 
Quote:
Originally Posted by tubeheadEL34 View Post

RE Lens Flare

My TV is the hitachi 51f500. I lined it with the black felt a few years ago, but it did not reduce the lens flare when the picture has a bright object against a dark background. I also clean the optics every year but this set has had this problem since day one. It is not major, but something you are aware of when you know where to look. I've read threads where crt owners talk about "lens striping" to take care of this widely reported problem.

Lens striping is for white field uniformity, not for lens flare.

b
post #7273 of 12297
Quote:
Originally Posted by Splicer010 View Post

Turn the brightness/contrast down. This is classic of a set being left in 'torch' mode.

oh gawd, that's your advice? the set's been professionally calibrated since day one as i mentioned earlier. Lens flare has nothing to do with contrast/brightness settings.
post #7274 of 12297
Quote:
Originally Posted by tubeheadEL34 View Post

oh gawd, that's your advice? the set's been professionally calibrated since day one as i mentioned earlier. Lens flare has nothing to do with contrast/brightness settings.

It does depend on the individual "professional" calibrator. If the TV has poor design, there are some things that reducing Contrast (NOT BRIGHTNESS) helps. Most all CRTs increase in resolution as contrast is reduced, even below optimal. It is especially noticeable with HD.
post #7275 of 12297
Of course Glen, that goes without saying, contrast should be way down compared to store settings. A pro that would choose otherwise is incompetent. I thought we were way beyond needing to remind people to turn the contrast and brightness down on this forum. Even my grandmother knows this. What's irritating is that the previous poster does not ask me what my settings are but tells me to get out of torch mode!! Since we're exchanging pearls of wisdom, here's some advice for you guys: for better sound use dedicated speakers instead of tv speakers, for better blacks, don't let the sun shine full strength on the screen while watching tv, when watching a widescreen movie, don't zoom in to get rid of the black bars on the top and bottom of the screen (they are supposed to be there).

No harm no foul...all in jest
post #7276 of 12297
My TV is a Hitachi 57F710. I just got my avia II disc, Is there anything i need to do before running the disc? I already cleaned the optics and lined with black felt.
Thanks
post #7277 of 12297
Quote:
Originally Posted by tubeheadEL34 View Post

RE Lens Flare

My TV is the hitachi 51f500. I lined it with the black felt a few years ago, but it did not reduce the lens flare when the picture has a bright object against a dark background. I also clean the optics every year but this set has had this problem since day one. It is not major, but something you are aware of when you know where to look.

Are you guys saying that your sets don't have this problem?

I, for one, am not saying that. My Pioneer 610 has also had this problem from day 1 despite all my efforts. (I lined with Duvetyne before it went out of style.) It's unavoidable, part of the nature of the beast.
post #7278 of 12297
So, I tried re-focusing my Mits WS-55315. Honestly, I think I did pretty well. I half followed Mr. Bob and half followed the service manual. The service manual would have me cover two lenses at a time while supplying a crosshatch pattern and focus it that way. Mr. Bob would have me use his "Cantilever Technique".

I never realized how out of focus red and green were. It was amazing. No scan lines went to very well defined scan lines without even really trying.

I don't really know what to do about blue, though. I was never really able to get the blue scan lines to show the same way that the red and green were. But, holy crap, those two made a hell of a difference.
post #7279 of 12297
Quote:
Originally Posted by phekno View Post

So, I tried re-focusing my Mits WS-55315. Honestly, I think I did pretty well. I half followed Mr. Bob and half followed the service manual. The service manual would have me cover two lenses at a time while supplying a crosshatch pattern and focus it that way. Mr. Bob would have me use his "Cantilever Technique".

I never realized how out of focus red and green were. It was amazing. No scan lines went to very well defined scan lines without even really trying.

I don't really know what to do about blue, though. I was never really able to get the blue scan lines to show the same way that the red and green were. But, holy crap, those two made a hell of a difference.

Now if you haven't clean the lenses, after cleaning and re-focusing you would think it's a different tv, better than NEW!
post #7280 of 12297
Thread Starter 
Quote:
Originally Posted by tubeheadEL34 View Post

RE Lens Flare

My TV is the hitachi 51f500. I lined it with the black felt a few years ago, but it did not reduce the lens flare when the picture has a bright object against a dark background. I also clean the optics every year but this set has had this problem since day one. It is not major, but something you are aware of when you know where to look.

Have you done the deeper optics cleaning? Have you performed the tests that show you whether you need to? If not and your set needs it, only 40% of the optics cleaning has yet been done. That other 60% might be just the ticket to making your lens flare so innocuous you won't notice or be distracted by it anymore. Of course if it has been there since day one this can't be the culprit. But if it has grown to be a lot more substantial problem over the years, this could be it.

All CRT RPTVs have some level of lens flare - as has been said above, it's endemic to the genre. The trick is to get your optical path so dazzlingly crystal clear - and the internal reflections dampened - that that flaring goes way into the background and becomes totally undistracting anymore.


b
post #7281 of 12297
Thread Starter 
Quote:
Originally Posted by phekno View Post

So, I tried re-focusing my Mits WS-55315. Honestly, I think I did pretty well. I half followed Mr. Bob and half followed the service manual. The service manual would have me cover two lenses at a time while supplying a crosshatch pattern and focus it that way. Mr. Bob would have me use his "Cantilever Technique".

I work on just one color at a time too, along with using a 480i/p crosshatch or circlehatch grid, at nice medium mid-light levels.

There are various ways to do just one color at a time. One is cover the other 2 lenses, another is to turn of 2 of them in service menu, another is to separate the grids by making the crosshairs go in a diagonal placement, then go back to the hatch grid.

Be sure to do the electronic focusing on an average light level picture. Using a high light level pic, you will have a mismatch, and it won't look right on regular video material.

There's a lot more to accurate optical and electrostatic focusing than just the Cantilever Technique. Which is still the best in the world for optical focusing BTW, IMHO...



b
post #7282 of 12297
I think my Mitsubishi RPTV is ready to die.

I turned the set on today and watched for about 15 minutes. I left the room and when I came back a minute later, the screen was completely white. I could faintly see the images on the screen, but it looks as if the television is submerged under a pool of milk.

I checked the settings and everything was set to normal. I unplugged the TV for 15 seconds and plugged it back in and suddenly everything was back to normal...but only for a minutes. The screen began to flash white and now its back to looking like milk.

Any ideas? Is it a power supply issue? The set is 10 years old.
post #7283 of 12297
Thread Starter 
Quote:
Originally Posted by phekno View Post

So, I tried re-focusing my Mits WS-55315.

I don't really know what to do about blue, though. I was never really able to get the blue scan lines to show the same way that the red and green were. But, holy crap, those two made a hell of a difference.

Blue is always the most challenging color to see. Best to do the focusing in the dark, rather than with lights of any kind on.

Optical/mechanical focusing should always be done to the tolerance of a gnat's eyebrow on all colors. That's why I came up with the Cantilever Technique years ago, long before HD. I was not satisfied with the humdrum focusing that was typically done with the other methods at the time. I had to get it the best it could be: as long as the scheimpflug and the inner-vs.-outer focusing balance are correct on your lenses, after you apply the Cantilever Technique the mechanical focusing can't be further improved, which was my ultimate goal. And it does so without doing any changes in the existing focusing, JIC that focusing is already dead on.

However, a slight defocussing of the blue is allowable electrostatically on the Focus trimpots, and was always done as SOP on the big ceiling pj's back then. These days with HDready's, it's not necessary. But still OK if your blue elec focus is slightly off, as blue is more a fill color than the actual structure colors that red and green are.

However, keep in mind that changing the setting of the blue Focus trimpot will change your white balance - the level of blue in your whites. When as tightly focused as possible, the whites will be not as brilliantly blue-white as they will be when slightly out of focus. This may or may not adversely affect your grayscale, depending on how well it has been set up when you make any changes in that blue Focus trimpot.

If your set was grayscaled at the factory to have inappropriately brilliant blue-whites just to compete in the brightly-lit marketplaces of BB, CC, Costco etc., tightening up the focus on your blue trimpot can get you back to where your blue Drive levels shoulda been all along, delivering the proper shade of gray thruout the IRE light levels rather than having the whites have balls to the wall stronger blue in their whites than in their darks. Which is how most HDreadys were set up at the factory, with the exception of the Mit's. The Mits usually have lots of overly done red in the drives of their grayscales, not blue. None of those brands were usually sent out with accurate grayscales, for various marketing reasons.

Back then we needed that slight defocusing, as the blue phosphors were not as strong as today's are. Today we don't, so we recommend tightly focusing the blue trimpot at all times on HDready CRTs.


Now we come to the interactivity of the controls used to realign the grayscale. Playing with the blue focusing (and the Screen trimpots on all colors) are the only ways to play with grayscale that do not involve interactivity of the blue whites to the blue darks. You can get away with reducing the blue in your whites this way without affecting the blues in your darks. But that's where the ability to isolate your correction ends.

Unfortunately due to the nature of grayscale and the way it tracks, when it comes to adjusting the Cutoffs and Drives of your grayscale registers, you can't just adjust down an overly saturated color in the whites without also compensating for what that does to the same color in the darks of your grayscale pattern. On some brands the whites are directly proportional to the darks, on some the whites are inversely proportional to the darks, in terms of what changing one does to the other.

But on each of the colors, the lights and the darks are interactive with each other within that particular color whenever you make changes to any of the colors in the grayscale op. Whenever you change anything about one color, you have to make changes to compensate within that color for what that does to the opposing light level of that same color.

Since any changes in one color affect the balance you have between that and the other colors, you may then have to make changes there too.

Rebalancoing your grayscale is much like tugging on one facet of a 6-piece hanging mobile. That one piece is never the only thing that moves, in that case...



Now you see why ISF was needed back then and will continue to stay needed, as there are many facets to doing an accurate grayscale. What's been mentioned here only scratches the surface of a completely-aligned grayscale op.


b
post #7284 of 12297
I need to move my PRO610HD that's been stored in an extra room inside for the last couple years into my den/office, and the only way it's going through the doorway is to put it on a furniture dolly on it's side. My wife and I tried to roll it in tonight and it missed going in by about 1". DOH! Anyway, will it hurt anything just to put it on it's side to just roll it through the doorway and then set it back down right away? I don't want to get rid of this set and was hoping to make my den/office a real "Man Cave" with this beast.
post #7285 of 12297
Do you mean up on one of it's small sides, as in placing up on a dolly on the left or right side of the set? If so, it don't sound like a good idea to me. I'd be worried that with doing that, that it might move or damage the mirror in some way
post #7286 of 12297
Quote:
Originally Posted by Johnla View Post

Do you mean up on one of it's small sides, as in placing up on a dolly on the left or right side of the set? If so, it don't sound like a good idea to me. I'd be worried that with doing that, that it might move or damage the mirror in some way

Yes-On one of the sides.
post #7287 of 12297
Thread Starter 
No problemo. I used to do this all the time when I was in charge of transporting these sets from the owner's home to the shop I worked at and back, for repairs. We used a carpeted van, and I was putting them into the van and transporting them on their sides all the time. They wouldn't fit in the van right side up.

Don't worry, the entire thing is solid state except the guns themselves, but they are very hardy. And the mirror is very tightly held in, it's not going anywhere no matter how it's transported. Whether they are transported on their sides or right side up, everything inside the unit still receives the same amount of torsion stress, and they were designed to be transported all over the US and to other countries as well.

If moving sets like this, I would recommend lots of padding to reduce the road shock. Bur for your purpose, no, just do it. Unless you rig up tons of interfering vibrations, you should have ho problems at all transporting it on its side thru a doorway.


b
post #7288 of 12297
^^^^
Ehh ... coolent leak worries???
post #7289 of 12297
Is there anyway to take the back part of this tv off to help get it around a tight corner??? Sony Model #KP61V45
LL
post #7290 of 12297
Quote:
Originally Posted by StevenC56 View Post

I need to move my PRO610HD that's been stored in an extra room inside for the last couple years into my den/office, and the only way it's going through the doorway is to put it on a furniture dolly on it's side. My wife and I tried to roll it in tonight and it missed going in by about 1".

If the door itself is in the way because it doesn't open a full 180°, take the door off the hinges. I have a few doors in my house which need to come off to move Big Things.
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