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Don't dump your CRT RPTV! - Page 343

post #10261 of 11764
1/25/12 at 12:43pm
On my 73" MIT CRT, I noticed on the convergence screen that the blue lines are a little blurry and thus thicker than the red lines the closer to the screen edge they get, most notably near all four corners. In the center of the screen and on most of the screen the lines look fine. The convergence on the set is all adjustable and holds fine; aside from a little bit of blue bleed on the extreme edges when there is a black/bright white intersection, the pq is amazing.

From what I've read, this has to do with focus of the blue gun, but I haven't been able to find out how/if this is/can be adjusted. I have the service manual, so I can get into the service menu, but I really don't want to accidentally mess anything up poking around. Maybe I'm totally off and this is something else. Thoughts?
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post #10262 of 11764
1/25/12 at 1:52pm
Thread Starter 
Spring for a phone session with me and I'll make sure you stay on the straight and narrow. Yes, there are 2 sets of focuses in there, and both need to be dialed in just right.

Contrast is overall light level, and it needs to be at its midpoint, which on a Mit is around 35-40% up on the Contrast bar graph. NOT at the bar graph midpoint, which is already 80-90% up!

Bleeding of any particular color is usually from having contrast up too high, and sometimes color intensity as well.

b
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post #10263 of 11764
1/25/12 at 5:56pm
Quote:
Originally Posted by ejohnsto View Post

On my 73" MIT CRT, I noticed on the convergence screen that the blue lines are a little blurry and thus thicker than the red lines the closer to the screen edge they get, most notably near all four corners. In the center of the screen and on most of the screen the lines look fine. The convergence on the set is all adjustable and holds fine; aside from a little bit of blue bleed on the extreme edges when there is a black/bright white intersection, the pq is amazing.

From what I've read, this has to do with focus of the blue gun, but I haven't been able to find out how/if this is/can be adjusted. I have the service manual, so I can get into the service menu, but I really don't want to accidentally mess anything up poking around. Maybe I'm totally off and this is something else. Thoughts?

I personally went through and did both electrostatic as well as mechanical focus on mine and discovered that the green and blue just can't be sharpened up very much, if at all. I'm guessing the previous owner left it in torch mode the whole time and the tubes just lose that "jazz" over time. Now when we watch 480p content, the red edges are crisp while green and blue are blurry by comparison. I was considering going and just defocusing the red to match the deterioration of the green and blue.

- 2B
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post #10264 of 11764
1/25/12 at 9:29pm
Thread Starter 
Quote:
Originally Posted by 2 Bunny View Post

I personally went through and did both electrostatic as well as mechanical focus on mine and discovered that the green and blue just can't be sharpened up very much, if at all. I'm guessing the previous owner left it in torch mode the whole time and the tubes just lose that "jazz" over time. Now when we watch 480p content, the red edges are crisp while green and blue are blurry by comparison. I was considering going and just defocusing the red to match the deterioration of the green and blue.

- 2B

Don't give up hope on it before you hire me on the phone for an hour. You might be surprised -

b
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post #10265 of 11764
1/25/12 at 10:02pm
Quote:


I was considering going and just defocusing the red to match the deterioration of the green and blue.

What?! Do you just want to totally hose the pic? Have Bob help...an investment.
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post #10266 of 11764
1/26/12 at 4:35am
Quote:
Originally Posted by Mr Bob View Post


Don't give up hope on it before you hire me on the phone for an hour. You might be surprised -

b

Are you sure? For all I know, this thing could've been left on 24/7 in torch mode before I got it.

- 2B
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post #10267 of 11764
1/26/12 at 9:08am
Went to watch a Fox program that I'd DVR'd the other day, and got a little surprise. Somebody in the broadcast booth decided to send out over the air Fox's frame line chart. I've seen color bars before, but never this on TV! Anyways, as somebody that has filmed these very charts for some of the shows I've worked on, I knew exactly what I was looking at. (click on pic to make larger)

Attachment 235372

As you can see, you've got your 4:3 pumpkin (edge markers), 16:9, both what are considered TV safe. What that means is so long as info is contained within those markers, every TV should be able to see all info no matter what kind of overscan might be being employed. This obviously applies most to TVs from the CRT era. The arrows would indicate the absolute edge of picture signal that could go out. I've seen on a few people's flat panels where the very top of the picture is showing what I'd describe as white bleed, cause the station is pushing it right to those arrows and the TV is seeing beyond.

Anyways, those of you with a Blu Ray of Video Essentials or the like have probably seen these and used 'em on your sets to measure overscan. I only have a DVD copy, and in 480p the overscan on my Pioneer 510 isn't so bad. It's when I'm in HD that things have always been bad, but I didn't know how bad it actually was.

See, the guy in the broadcast booth displayed the frame chart twice. The first one seen above, well that one is windowboxed. This next one, this is what is actually broadcast. Why both were sent out, who knows, but I'm glad it happened.

Attachment 235373

HOLY CRAP!!

I never realized how much info I was really having cropped. It appears that it's off center too, as the right side is cropping more than the left. I mean you can't even see the right side markers! And check out how much I'm missing from the top and bottom. Picture is inside of the TV Safe zone, let alone not remotely close to the outer arrow edges! I've viewed shows where people's heads are cut cleanly off, but shrugged it off as bad composition, as usually there was a foreground element that was really the focus of the frame. Now I know.

So fellow 510 owners, is your overscan this atrocious?
LL
LL
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post #10268 of 11764
1/26/12 at 4:24pm
Re: Overscan on Pioneer 510

The overscan on my Pioneer 610 is very similar. It seems to have grown progressively worse since I purchased it in 2001.

I am not so bothered by it now since the kids use it with their Wii and I use obxdiver's nicely calibrated Mits 65813 for the HT. :-)

I am sure that the overscan issue is something that Mr. Bob could correct during calibration.
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post #10269 of 11764
1/26/12 at 4:33pm
Quote:
Originally Posted by pnj314159 View Post

Re: Overscan on Pioneer 510

The overscan on my Pioneer 610 is very similar. It seems to have grown progressively worse since I purchased it in 2001.

I am not so bothered by it now since the kids use it with their Wii and I use obxdiver's nicely calibrated Mits 65813 for the HT. :-)

I am sure that the overscan issue is something that Mr. Bob could correct during calibration.

I think our Mitt's HD is pretty bad, I remember having to compensate for the overscan quite a bit on the Xbox. 480p overscan was just unacceptable and had to be fixed in the service menu, which led to a very slight geometry distortion. I adjusted it quite a bit (still on the 480) and there's still quite a bit of cropping.

- 2B
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post #10270 of 11764
1/26/12 at 5:30pm
I only feed 1080i to the Mits via a Lumagen processor. Overscan is set to ~2%. I've never used the set to display 480p so I can't comment on the overscan there.

My understanding from reading this thread is that overscan on RPCRTs is not trivial to correct.
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post #10271 of 11764
1/26/12 at 6:15pm
Thread Starter 
Quote:
Originally Posted by 2 Bunny View Post

Are you sure? For all I know, this thing could've been left on 24/7 in torch mode before I got it.

- 2B

If so, that's easily observed just by removing your screen and taking a flashlight in there and looking at the aging footprint. If it's browned out and really darkened, you have your answer.

If it's barely noticeable, you have loads of life still left in that baby, and it needs other attention.

b
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post #10272 of 11764
1/26/12 at 6:18pm
Thread Starter 
Quote:
Originally Posted by shutyertrap View Post

Went to watch a Fox program that I'd DVR'd the other day, and got a little surprise. Somebody in the broadcast booth decided to send out over the air Fox's frame line chart. I've seen color bars before, but never this on TV! Anyways, as somebody that has filmed these very charts for some of the shows I've worked on, I knew exactly what I was looking at. (click on pic to make larger)

Attachment 235372

As you can see, you've got your 4:3 pumpkin (edge markers), 16:9, both what are considered TV safe. What that means is so long as info is contained within those markers, every TV should be able to see all info no matter what kind of overscan might be being employed. This obviously applies most to TVs from the CRT era. The arrows would indicate the absolute edge of picture signal that could go out. I've seen on a few people's flat panels where the very top of the picture is showing what I'd describe as white bleed, cause the station is pushing it right to those arrows and the TV is seeing beyond.

Anyways, those of you with a Blu Ray of Video Essentials or the like have probably seen these and used 'em on your sets to measure overscan. I only have a DVD copy, and in 480p the overscan on my Pioneer 510 isn't so bad. It's when I'm in HD that things have always been bad, but I didn't know how bad it actually was.

See, the guy in the broadcast booth displayed the frame chart twice. The first one seen above, well that one is windowboxed. This next one, this is what is actually broadcast. Why both were sent out, who knows, but I'm glad it happened.

Attachment 235373

HOLY CRAP!!

I never realized how much info I was really having cropped. It appears that it's off center too, as the right side is cropping more than the left. I mean you can't even see the right side markers! And check out how much I'm missing from the top and bottom. Picture is inside of the TV Safe zone, let alone not remotely close to the outer arrow edges! I've viewed shows where people's heads are cut cleanly off, but shrugged it off as bad composition, as usually there was a foreground element that was really the focus of the frame. Now I know.

So fellow 510 owners, is your overscan this atrocious?



Welcome to the real world.

Yup, they were all like that, all CRT RPTVs. I have been correcting that for at least a decade in my calibrations, one reason overscan reduction has become a highly popular staple in my calibration arsenal.

Good news is, it's ALL recoverable. What's missing hasn't been eliminated at all - it's all still there, you're just not seeing it. And when you get your overscan reduction done via the shimming op, you get an improvement in depth to boot. There are extensive pictures in this thread and others, showing before and after what I lovingly call O'scan Redux.

b
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post #10273 of 11764
1/26/12 at 6:24pm
Wow, this reminds me of the good ol' days when I lusted after 32" Sony Trinitron XBR's because they had perfectly flat screens and comb filters.

Too bad the media and players were such crap back then; I mean, s-vhs was a complete joke. Then again, laserdisc players were around back in the late 80's/early 90's, so it wasn't all bad.
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post #10274 of 11764
1/26/12 at 6:26pm
Quote:
Originally Posted by Mr Bob View Post



Welcome to the real world.

Yup, they werll like that, all CRT RPTVs. I have been correcting that for at least a decade in my calibrations, one reason overscan reduction has become a highly popular staple in my calibration arsenal.

Good news is, it's ALL recoverable. What's missing hasn't been eliminated at all - it's all still there, you're just not seeing it. And when you get your overscan reduction done via the shimming op, you get an improvement in depth to boot. There are extensive pictures in this thread and others, showing before and after what I lovingly call O'scan Redux.

b

Given that all of these sets have miles on them, does overscan reduction reveal the difference between the unused part and used part of the cathodes?

Also, can you describe the difference between overscan reduction mechanically achieved versus that accomplished by video processor?
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post #10275 of 11764
1/26/12 at 7:44pm
Okay, I have a 57f59a that I bought back in 2006, it is in fantastic shape, blu ray looks marvelous ---BUT BUT there are screen burns which I notice (I haven't told anyone because others dont notice) it would be noticed on a lighted screen -- it is my fault!!! When I first bought this set I was totally ignorant about contrast settings. My question is does the snowing effect help fade in burns?

Thanks.
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post #10276 of 11764
1/26/12 at 8:06pm
Burn-in is permanent.
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post #10277 of 11764
1/28/12 at 7:33am
Does anyone have an opinion on the Mitsubishi,.WS 65807 ? Is this too old of a set to consider ? From some research I've done I'm assuming that this model has the 7" guns, should I hold out and continue my search for a model with the 9" guns ? It would be about a 3hr trip each way to look at this.Physically looks in nice shape,but the lady owner can't figure out how to get into the settings to see where contast and other setting are at.Also I'm a little confused is this model HD ready or is a separate tuner need ? I don't that matters much to me as I use the DirectTV HD Tuner.

I'm still using my Hitachi 51F59,but I'm looking for a service manual to do some tweaking and experimenting.I have the User Manual,but that's pretty much useless.I've been through a bunch of the threads,but if someone could point me into the direction of a detailed description to remove the screen to clean my optics,I would greatly appreciate it.Or do I just start with the 18=20 screws on the backside.I'm pretty mechanically inclined if I just have the proper instructions.

Great thread by the way.

Greg
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post #10278 of 11764
1/28/12 at 8:02am
Quote:
Originally Posted by mikrawdad View Post

Does anyone have an opinion on the Mitsubishi,.WS 65807 ? Is this too old of a set to consider ? From some research I've done I'm assuming that this model has the 7" guns, should I hold out and continue my search for a model with the 9" guns ?...

...Great thread by the way.

Greg

Bob's the expert on these sets, so you'll get a sagacious response from him.

All I can say is that 9 inch tubes projecting against a 65 inch screen is very interesting.
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post #10279 of 11764
1/28/12 at 9:10am
Quote:
Originally Posted by mikrawdad View Post

Does anyone have an opinion on the Mitsubishi,.WS 65807 ? Is this too old of a set to consider ? From some research I've done I'm assuming that this model has the 7" guns, should I hold out and continue my search for a model with the 9" guns ? It would be about a 3hr trip each way to look at this.Physically looks in nice shape,but the lady owner can't figure out how to get into the settings to see where contast and other setting are at.Also I'm a little confused is this model HD ready or is a separate tuner need ? I don't that matters much to me as I use the DirectTV HD Tuner.

I'm still using my Hitachi 51F59,but I'm looking for a service manual to do some tweaking and experimenting.I have the User Manual,but that's pretty much useless.I've been through a bunch of the threads,but if someone could point me into the direction of a detailed description to remove the screen to clean my optics,I would greatly appreciate it.Or do I just start with the 18=20 screws on the backside.I'm pretty mechanically inclined if I just have the proper instructions.

Great thread by the way.

Greg

On my old Hitachi i removed the back to clean the mirror and guns you will notice the difference with just the cleaning for sure if it has never been done before
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post #10280 of 11764
1/28/12 at 9:52am
Quote:
Originally Posted by Mr Bob View Post

Good news is, it's ALL recoverable. What's missing hasn't been eliminated at all - it's all still there, you're just not seeing it. And when you get your overscan reduction done via the shimming op, you get an improvement in depth to boot. There are extensive pictures in this thread and others, showing before and after what I lovingly call O'scan Redux.

b

Or you can build an HTPC. Yes, having done the video calibrations and the audio calibrations, that was my most recent insane adventure.

Michael
Hitachi 57F59A
LL
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post #10281 of 11764
1/28/12 at 10:13am
Quote:
Originally Posted by sideswiper View Post

On my old Hitachi i removed the back to clean the mirror and guns you will notice the difference with just the cleaning for sure if it has never been done before

Absolutely agree. With my other RPTV a cleaning produced a night and day difference.

But after reading Bob's posts, I would follows his comments and instructions precisely. You might think the cleaning materials and procedures you might be using are appropriate and mild, but then find out they're scratching or dulling the optics. Your whole optical path, including mirror, is important.
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post #10282 of 11764
1/28/12 at 11:12am
Yes I've read his posts on what product and the procedure,did I miss how to access this ? I've had the set about 4 1/2 years,but since I've started following this thread it seems like the picture is getting duller
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post #10283 of 11764
1/28/12 at 11:32am
Quote:
Originally Posted by mikrawdad View Post

I'm still using my Hitachi 51F59,but I'm looking for a service manual to do some tweaking and experimenting.I have the User Manual,but that's pretty much useless.I've been through a bunch of the threads,but if someone could point me into the direction of a detailed description to remove the screen to clean my optics,I would greatly appreciate it.Or do I just start with the 18=20 screws on the backside.I'm pretty mechanically inclined if I just have the proper instructions.

Great thread by the way.

Greg

You can start here:
http://www.avsforum.com/avs-vb/showt...90702&page=153
http://www.avsforum.com/avs-vb/showt...87477&page=157
You have a LOT of catching up to do!
PM me about a pdf of the service manual.
Michael
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post #10284 of 11764
1/28/12 at 12:07pm
Quote:
Originally Posted by mikrawdad View Post


I'm still using my Hitachi 51F59,but I'm looking for a service manual to do some tweaking and experimenting.I have the User Manual,but that's pretty much useless.

Here is a web site to D/L the service manuals for free.
Note: There is a D/L limit of 2 D/L's per day for non members of the site.

http://elektrotanya.com/?q=showresul...oria=&kat2=all
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post #10285 of 11764
1/28/12 at 12:43pm
Thread Starter 
Service manuals are a lot better than user manuals, but have significant limitations. They give you the nuts and bolts, but don't coach you in how to use them. They also don't give you insights into the finer points of the convergence system so you can really fine tune it, and they don't specify how the different convergence systems work brand by brand, and what their fine little oddities are. Believe me, they are legion! But when mastered, allow you to really dial it in. Only experience brings that all home to roost.

I am available for phone consultation/coaching on these issues. In many cases I am the only resource you will ever get access to for these things. Most formerly CRT calibrators no longer do CRT at all, they have been lured away by the promise of quick, easy calibrations on fixed pixel.

While tempting, I still get a charge out of taking a CRT set and bringing it back alive, with the results speaking for themselves.

And for a fraction of what a similar grade fixed pixel costs, new. When you have a 20 year service life display, like our CRT RPTVs - and FPTVs - are, there's really no need to buy new.



b
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post #10286 of 11764
1/28/12 at 1:43pm
Quote:
Originally Posted by Mr Bob View Post

If so, that's easily observed just by removing your screen and taking a flashlight in there and looking at the aging footprint. If it's browned out and really darkened, you have your answer.

If it's barely noticeable, you have loads of life still left in that baby, and it needs other attention.

b

I'll have to take a look at that.

Say, did you ever get anywhere with that Barco CRT FP in your garage you were talking about before?

Quote:
Originally Posted by Mr Bob View Post



Welcome to the real world.

Yup, they were all like that, all CRT RPTVs. I have been correcting that for at least a decade in my calibrations, one reason overscan reduction has become a highly popular staple in my calibration arsenal.

Good news is, it's ALL recoverable. What's missing hasn't been eliminated at all - it's all still there, you're just not seeing it. And when you get your overscan reduction done via the shimming op, you get an improvement in depth to boot. There are extensive pictures in this thread and others, showing before and after what I lovingly call O'scan Redux.

b

Interesting. Now, how does that overscan work? I mean, is the whole image on the tube and just being projected into somewhere other than the screen, or is the image cut off on the face of the tube?

- 2B
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post #10287 of 11764
1/28/12 at 5:50pm
Well God hates a coward,finally cleaned the old girl out.Started by removing the lower back panel,I could have cleaned the lenses but couldn't get to the mirror from there,but I could see how dirty it was.So the screen had to come off.As I suspected the 16 screws on the back needed to be removed,along with the 8 under the front speaker grill cover.Once it was opened I was surprised at how simple it looked.Some of the pictures that were posted in the threads had me a little confused,but once open it all made sense.The lenses were dusty,the mirror was dirty with a smokey film and there were a ton of cobwebs in there.

My local Ace Hardware had the Sprayway glass cleaner and I found some paper towels that were made without bleach and was on my way.Soaking the paper towels and carefully dabbing each lens.I also now know why the mirror was the tough part.I always seemed to find another streak.I was a little intimidated at the start,but believe the process was completely worth it.In less than 2 hrs total work time I did see the improvement.Next year when I do this I will probably do the glare reduction by painting the inside black,which I saw in a different thread.I think the greatest improvement is in the corner.Just seems clearer.Lots of great tips in here,just need to be patient when preforming them.

I'm going to keep looking for the bigger Mitsubishi's but I can be patient and I won't be scared to take it apart and try some low level stuff.Thanks for the encouragement and great tips.
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post #10288 of 11764
1/28/12 at 5:55pm
Quote:
Originally Posted by 2 Bunny View Post

Interesting. Now, how does that overscan work? I mean, is the whole image on the tube and just being projected into somewhere other than the screen, or is the image cut off on the face of the tube?

- 2B

Unless I'm mistaken, it's not cut off on the tube. That's why the shim mod is possible. I just can't afford to have it done. I'd attempt a DIY, but geometry scares me!
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post #10289 of 11764
1/28/12 at 8:38pm
Thread Starter 
Quote:
Originally Posted by 2 Bunny View Post

I'll have to take a look at that.

Say, did you ever get anywhere with that Barco CRT FP in your garage you were talking about before?

It's still there, standing up against the wall. Have had no time or inclination to set it up, my life has been to intense! But the other front projectors, now that's a different story, as it's a paid gig.

Jim the owner - a retired aerospace engineer and experienced troubleshooter who has extensive experience in satellites - and I have successfully troubleshot and brought back to life 4 909s and 2 812s so far, just need the parts to be delivered and installed. We have 2 more 812s, the Barco Reality series - the ones with the 12" guns used in government flight simulators - to go, as far as repair goes, and all of them will need to be calibrated once they are all working again. I will be at this for a while!

The 4 909s - with 9" guns - will be firing on a 40' long, 10' tall one piece screen, with blend technology feathering all 4 pix together.


Quote:


Interesting. Now, how does that overscan work? I mean, is the whole image on the tube and just being projected into somewhere other than the screen, or is the image cut off on the face of the tube?

- 2B

It's all there on the face of the tube all right. They got that part of it right. That's why the shimming op is the best way to go. The gun array was simply placed too far away from the screen, on purpose, to hide the flaws out at the edges that they didn't want to invest the time correcting.

b
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post #10290 of 11764
1/28/12 at 8:49pm
Thread Starter 
Quote:
Originally Posted by mikrawdad View Post

Well God hates a coward,finally cleaned the old girl out.Started by removing the lower back panel,I could have cleaned the lenses but couldn't get to the mirror from there,but I could see how dirty it was.So the screen had to come off.As I suspected the 16 screws on the back needed to be removed,along with the 8 under the front speaker grill cover.Once it was opened I was surprised at how simple it looked.Some of the pictures that were posted in the threads had me a little confused,but once open it all made sense.The lenses were dusty,the mirror was dirty with a smokey film and there were a ton of cobwebs in there.

My local Ace Hardware had the Sprayway glass cleaner and I found some paper towels that were made without bleach and was on my way.Soaking the paper towels and carefully dabbing each lens.I also now know why the mirror was the tough part.I always seemed to find another streak.I was a little intimidated at the start,but believe the process was completely worth it.In less than 2 hrs total work time I did see the improvement.Next year when I do this I will probably do the glare reduction by painting the inside black,which I saw in a different thread.I think the greatest improvement is in the corner.Just seems clearer.Lots of great tips in here,just need to be patient when preforming them.

I'm going to keep looking for the bigger Mitsubishi's but I can be patient and I won't be scared to take it apart and try some low level stuff.Thanks for the encouragement and great tips.

Remember that those gritty particulates need to be suspended in liquid before they can be safely moved. Best way to do that is to spray the lens directly, but being very careful to not allow any liquid to penetrate the edges and get to the lower lenses, where it will fog things up.

Let it sit there for 15 seconds before going at it with your paper towels, and NEVER go back and forth over the lenses with the paper towels! One thorough swipe at a time, always lifting up from the lens, never down onto it, never trapping any of those gritty particulates against it nor grinding them into it!

b
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