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Don't dump your CRT RPTV! - Page 373

post #11161 of 12305
Pioneer, yeah i wish biggrin.gif Just a lowly hitachi uwx20b so i'm not sure how dirty the internal optics get over time.
I don't think this tv was used much either, after I cleaned off the lenses and mirror when I first got it I was quite shocked at how bright it was for a 10 year old display.

It's definetly the opposing side reflections that i'm getting, a crescent of sorts can it be mitigated with duvetyne or felt or is it likely to be within the lense casings?

Having never owned one of these displays before i can't really tell you if it's bleary, i know it was pretty bad when I got it and it's alot better now, i don't expect the world out of crt's for static contrast but it beats the px80u plasma i had for dark room viewing.
post #11162 of 12305
Thread Starter 
Quote:
I've noticed in relatively high contrast shots though black hair can look slightly crushed. Am i correct in thinking tweaking the cutoff controls as a whole will help remedy it? I brought them up 6 notches or so (keeping track of everything with photos of course biggrin.gif )
and it seems to have helped but it probably effects the white cutoff to right?

Or you could have simply goosed up the master sm brightness a bit instead, which affects all 3 colors automatically. Don't want to get it too far from its midpoint, tho, or it will slew colors off, away from having the gray have fidelity.

Setting master brightness/black level is critical to excellent viewing, and at the same time, some content will need more and some less. It may need to be fine tuned per program material.
Quote:
I worked out sharpness as well, from focusing to setting to the accurate movie mode with subtle svm, it looks nearly as sharp as any plasma i've owned smile.gif

Awesome!
Quote:
I'm also looking into to what i believe is called duvatyne? I hear it's a great way to minimize unwanted reflections inside the set. As this is a freebie is it worth investing in enough of this material to coat the inside of the set?

Yes. At the same time it does not compare with the huge improvements made by full blown optics cleaning.
Quote:
Thanks for all the help from everyone on this board, i won't be dumping my crt anytime soon smile.gif

Great report!

wink.gif

b
Edited by Mr Bob - 8/17/12 at 1:09pm
post #11163 of 12305
Thread Starter 
Quote:
Originally Posted by Mik James View Post

Pioneer, yeah i wish biggrin.gif Just a lowly hitachi uwx20b so i'm not sure how dirty the internal optics get over time. I don't think this tv was used much either, after I cleaned off the lenses and mirror when I first got it I was quite shocked at how bright it was for a 10 year old display.

I coulda told you that -
Quote:
It's definetly the opposing side reflections that i'm getting, a crescent of sorts can it be mitigated with duvetyne or felt or is it likely to be within the lense casings?
Having never owned one of these displays before i can't really tell you if it's bleary, i know it was pretty bad when I got it and it's alot better now, i don't expect the world out of crt's for static contrast but it beats the px80u plasma i had for dark room viewing.


Expect.

There's nothing better than CRT for contrast ratio, whether you're talking static or dynamic. If yours is not cutting it, we need to talk.

wink.gif

b
Edited by Mr Bob - 8/17/12 at 1:24pm
post #11164 of 12305
"Or you could have simply goosed up the master sm brightness a bit instead, which affects all 3 colors automatically."

What's the master sm brightness? All i've touched in the service menu is the cutoff and gain controls. I should also mention i'm calibrating for slightly purple tinted glasses so there will probably be some imbalance.

"Yes. At the same time it does not compare with the huge improvements made by full blown optics cleaning."

I'm a "try the easiest things first" kind of guy biggrin.gif I'll probably end up doing it eventually though.

"I coulda told you that"

It seems like they went overboard in the improvements they made to the crt so they could perform at such a high brightness, I see single tube crt's dimming to nothing left and right so it was definetly a pleasant surprise smile.gif

"Expect.

There's nothing better than CRT for contrast ratio, whether you're talking static or dynamic. If yours is not cutting it, we need to talk."

That's a very long and complicated topic tongue.gif For my viewing environment and preferences crt's fit the bill pretty well, but alot of people like more brightness than i do and crt's static contrast seems to fall of exponentially as the brightness rises and the bright areas cover more of the screen, whether the human eye can detect benefits of the display tech in those circumstances is certianly up for debate.

So is felt likely to help mitigate these detail eating crescents or is it something that's buried in the optics?
It sounds like something that would take alot more work to improve: http://dgibbons.members.sonic.net/essay7.html

I'm surprised manufacturers didn't work harder to mitigate it.

An example of the kind of content i got this screen for: http://www.pcgames.de/screenshots/original/2011/12/Dragon_1.jpg
post #11165 of 12305
Thread Starter 
Contrast is the overall light level of the display, adjustable and best set at light level midpoint, in the middle of its linear operating range.

Brightness/black level is the shadow detail in the dark areas. Whether Contrast is high or low, Br/BL will have to be set to match/compensate.

They affect each other as far as the net effect on your viewing goes, but they don't really change each other in the process.

b
Edited by Mr Bob - 8/18/12 at 11:58am
post #11166 of 12305
Oh your talking about the basic menu video controls? Yeah I set black level to where a black screen nearly blends into the darkness for dark room viewing.
Contrast is usually set around 30.

So will felt lining work to mitigate lens flare crescents or are the reflections within the lens casings?
post #11167 of 12305
Thread Starter 
Yes.

It will help, but unless each internal lens surface is anti-reflective coated like a fine binocular ("Coated Optics"), telescope or microscope, there will be internal reflections between the lenses.

Of the 28 surfaces involved in your projected image's flight path, each of the 3 lens barrels has 4 lenses/8 parallel surfaces, 7 of which are right up against an adjoining lens. That's 21 opportunities to reflect light back and forth lens to lens, plus each of the 3 top lenses catching reflections off the glossy surface of the fresnel, the most internal part of the 2 layer view screen sandwich. So add 4 more - the lens tops and the rear of the view screen. That's 25 at least partially reflective surfaces in there.

This internal coating was done on the lenses of the early Advent triple gun projectors, but the pricepoint of CRT RPTVs would never allow for such frivolity, the common man - which was their target market share - would never spring extra for that.

It would also diminish the light level of the images getting out to the viewer to a certain degree.

b
Edited by Mr Bob - 8/18/12 at 12:26pm
post #11168 of 12305
Yeah the article i linked a few posts back talked about minimizing them by using an anti reflective paint inside the lens casings and on the edges of the lenses, sounds like something that's really easy to screw up leaving me with a 240 lb paper weight ;p

So if i'm following correctly, dirty internal optics will cause a haze around brighter objects and a decrease in brightness, where i would then turn up the contrast to compensate and lose black level performance in doing so while doing nothing for the haze.

Lining the cabinet will only get rid of some misplaced washout of dark areas upping the ansi contrast not doing anything for crescent shaped reflections that start inside the lenses.

I'm guessing that i'm calibrating for what most would consider a very low contrast setting which in turn will cause some crushing of detail near black, i've been trying to mitigate it with the cutoff controls but if say the screen controls were maybe set slightly to high (dimly visible up close in a dim room) would that cause the scale to crush some detail near black making it impossible for me to achieve true black without crushing close detail?
post #11169 of 12305
Thread Starter 
Nobody knows nuttin' until you have a crystal clear light path in there. There are tests that will tell you if you need to do the deeper optics cleaning, which I can guide you thru over the phone. Did that article cover the fact that there are no glass surfaces in there being cleaned or coated? You don't want to be applying anything to a plastic surface when that surface may curdle in response to it.

On a Pioneer you definitely will need the deeper optics cleaning. On a Hit I don't know, but I suspect that answer is yes as well.

Any Hitachi owners out there want to chime in? Leo? Michael?

b
Edited by Mr Bob - 12/1/12 at 1:20pm
post #11170 of 12305

I once found a bug in mine, so there's plenty of room for dust.

And it's no big deal. Take it slow, one lens at a time, and get some first-hand advice from Bob.

Michael

Hitachi 57F59A

post #11171 of 12305
Thread Starter 
Quote:
Originally Posted by Mik James View Post

Pioneer, yeah i wish biggrin.gif Just a lowly hitachi uwx20b

Hold the presses. Can't let that statement stand unanswered.

Properly dialed in Hitachi is no slouch and can deliver HD just as well as properly dialed in Pioneer. Hitachi usually has color decoder registers so that after your grayscale has been aligned properly you can finely tune your color for delicate authenticity, while Pioneer has no such registers. You're stuck with whatever their factory-designed color paradigm is. For Mit and Sony it is always red pushed, but we've been able to do away with that red push on the Mit's and Sony's for the most part. Again, not to be confused with too much red in the B/W material, which is a grayscale error.

Michael, Leo, give him the skinny on yours if you have a moment -

b
Edited by Mr Bob - 8/18/12 at 3:46pm
post #11172 of 12305
Quote:
Originally Posted by Mr Bob View Post

Michael, Leo, give him the skinny on yours if you have a moment -
b

"Skinny"? We got a whole damn thread:

http://www.avsforum.com/t/1010146/rpcrt-reference-material-color-decoding/960

post #11173 of 12305
Yeah I certainly could have done worse for 0$, I almost bought a Samsung and a Philips both priced at 100$,
I only read later about the frequent gun death of Samsung's and coolant contamination of the Philips.
I certainly hope the Pioneer elites are better though, considering what people paid for them.
post #11174 of 12305
Thread Starter 
They are

B
post #11175 of 12305
Thread Starter 
Quote:
Originally Posted by LastButNotLeast View Post

"Skinny"? We got a whole damn thread:
http://www.avsforum.com/t/1010146/rpcrt-reference-material-color-decoding/960

Thanks Michael.

And that's just 1 of at least 5 major Hitachi threads I have perused on AVS Forum over the years, all set up and contributed to by Hitachi owners for the benefit of other Hitachi owners.

Even I have learned a few things from them, which I practice with every Hitachi I do these days!

wink.gif

B
Edited by Mr Bob - 8/19/12 at 10:30pm
post #11176 of 12305
Yeah there weren't to many other options, i think it was down to a Sony from 2004 a Panasonic from 2003 and my hitachi from 2002. I had heard good things about the Sony's and good things on this thread and elsewhere about the Panasonics but all i had to do to get the hitachi was walk in and take it where as any other tv i was looking at was right around 100$.

You mention tests to see if deeper optics cleaning is needed, can you divulge one or two or are they trade secrets? biggrin.gif
post #11177 of 12305
Thread Starter 
Everything on these threads is free if you want to cruise thru them and if it exists here and you want to take your chances with each piece of info. And believe me bad info is out there, waiting to bite you on the butt once tried. Sometimes irrevocably. Like using microfibre cloths "Mr Bob said to." (I would never)

If you want to get intel reliably and personally and know that it's coming from the horse's mouth and you won't need to look any further, I recommend you get a whole bunch of questions together and contact me privately for a phone coaching session, as many here have done thru the years including Michael.

I have tons of very valuable information I give out every day, but some of it I'd rather keep close to the vest if you don't mind. It's hard-earned knowledge gleaned only through years of intense work on these sets.

I know you basically walked away with that set for essentially nothing and it's easy to think you can have that happen all the time if you play your cards right. Please recognize that you have saved incredible amounts of money - in the thousands - by your getting this deal vs. the poor sap who bought it new, and this thread being here for the last 7 years is one reason such incredible machines are still available on the used market and not all ground under by now, as the retailers did their best to do.

That being the case you might want to think about ways you could give back rather than continuously vying for the FREE card -



b
Edited by Mr Bob - 8/19/12 at 11:55pm
post #11178 of 12305
I didn't want to come off as a prick or anything and it's perfectly fine if you want to keep some information to yourself. I did indeed get an incredible deal and I appreciate that, hopefully I'll keep this tv running and eventually pass it on to someone who will do the same rather than the guy I got it from who couldn't have cared less about it. The poor sap who bought it new bought in a time when their was nothing else out there that could compete in any area, be it picture quality, value or even power draw. He also didn't have to carry It up and down flights of stairs and put 30 hours of work into it.

Considering I am currently broke until I finish the training for comptia a+ (and I mean 0$ broke) i can't afford things like phone coaching, unlike many who would simply hit and run I have tried to help others around the forum as much as I can with what little I know about other areas of electronics. That's about all I can afford to give back right now.
post #11179 of 12305
Quote:
Originally Posted by Mr Bob View Post

...

Any Hitachi owners out there want to chime in? Leo? Michael?

b

I would recommend to get a hold of the service manual. Research anything you want to perform to your tv.

Even then if you are sure what you are doing I would still recommend talking to Bob. He has invaluable knowledge that you can't find anywhere else.

Hitachis can be tweak to the max, the service registers have great flexibility, nevertheless this is not for everyone. It requires time and dedication to do it right. Like I mentioned before, if you want to get it right the first time get help from Bob, very well worth it.
post #11180 of 12305
Well maybe sometime in the future, but like I said, i'm broke :P

I picked up a service manual when i first got the tv, it helped out a little but this thread has been much more helpful.

I would love to eventually have my Hitachi tweaked to the max but i'm focusing on the little things right now that i have time to do while studying and that i can afford to do.

As always thanks for all the help smile.gif
post #11181 of 12305
Quote:
Originally Posted by Mik James View Post

...

I would love to eventually have my Hitachi tweaked to the max but i'm focusing on the little things right now that i have time to do while studying and that i can afford to do.

As always thanks for all the help smile.gif

Good luck to you... in the mean time you should check the thread Michael posted. There are very good and specific ideas for the Hitachis there, just remember to always write down your starting registers before changing anything.
post #11182 of 12305
Thanks man, i'll definetly check out the thread.

I always take photographs of any service menu values that i change.
post #11183 of 12305
Thread Starter 
And mark any changes before changing anything mechanical - like if you refocus your lenses make sure and mark your starting point on each and every lens first, so you will have an adequate bread crumbs trail back if you need it. And never give yourself the chance to mix the lenses up - if you remove one or another for deep optics cleaning, always totally complete with one lens and reinstall it, before moving on to the next.

Fine points, but critical once you're in the trenches.

All my intel is available one way or the other, thanks for respecting my wishes on how it gets out there. I know what it's like to be in your financial position and it's not something you want to allow for long. After having had open heart surgery in late June and not working for a while, I am close to that now myself!

wink.gif

b
Edited by Mr Bob - 12/1/12 at 1:25pm
post #11184 of 12305
Good luck to you smile.gif and thank you for your understanding as well. I'm hoping the a+ training will be my ticket into the electronics job market where I can work my way into other areas as well,
post #11185 of 12305
Mr Bob,

Any chance you have the Factory directions on how to split a Hitachi 65T500 in two? I know the top comes off somehow and I need to move mine from the downstairs to a friends house without breaking it. It has served me well for almost 9 great years. If I can't remove the top half I will have to junk it to get it outside. It would be a shame as it is STILL an awesome picture.

Thanks in advance if you can help,

Joe
post #11186 of 12305
I have parts available for a Mitsubishi WS-65903. Unfortunately I am scrapping the TV, but prior to recycling it, I wanted to see if anyone is interested.
I also have both full service manuals, schematics etc.
Probably best if you emailed me.
zoidsmith@aol.com
post #11187 of 12305
Thread Starter 
The 65" Mit that Jerome (zoidsmith) is giving away in the post above has been calibrated by me in the past and very well taken care of by him. He called me the other day and asked if I wanted it, but I currently have 4 CRT RPTVs at my place and cannot possibly consider taking in another one.

I told him to come here because of all the readers here who still love CRT tech and would relish a free 65".

It's fully functional, has not been parted out at all yet, and works fine. And it's FREE! Hop on it! Otherwise he'll part it out and recycle the remainder. As in have it crushed!

eek.gif

b
Edited by Mr Bob - 8/24/12 at 10:05am
post #11188 of 12305
Thread Starter 
Quote:
Originally Posted by 65T500 View Post

Mr Bob,
Any chance you have the Factory directions on how to split a Hitachi 65T500 in two? I know the top comes off somehow and I need to move mine from the downstairs to a friends house without breaking it. It has served me well for almost 9 great years. If I can't remove the top half I will have to junk it to get it outside. It would be a shame as it is STILL an awesome picture.
Thanks in advance if you can help,
Joe

I don't, but if it's a 65" Hit, yes it can be separated. Contact the owners in the Hitachi threads here on the AVS. One was mentioned just a few posts back, here on this thread.

How to separate it is usually explained in the User manual it came with. If lost by now, that kind of thing can be downloaded very economically these days at www.servicemanuals.net -

b
Edited by Mr Bob - 8/24/12 at 10:08am
post #11189 of 12305
Quote:
Originally Posted by Mr Bob View Post

The 65" Mit that Jerome (zoidsmith) is giving away in the post above has been calibrated by me and very well taken care of by him. He called me the other day and asked if I wanted it, but I currently have 4 CRT RPTVs at my place and cannot possibly consider taking in another one.
I told him to come here because of all the readers here who still love CRT tech and would relish a free 65".
It's fully functional, has not been parted out at all yet, and works fine. And it's FREE! Hop on it! Otherwise he'll part it out and recycle the remainder. As in have it crushed!
eek.gif
b

I presume he's on YOUR side of the continent?

wink.gif

Michael

post #11190 of 12305
Thread Starter 
Unfortunately for those of you on the other side, yes...!

He's in Antioch, CA, just North of SF a ways.

b
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