Question about rear projection TVs

blue_harvester · 15-12-2004, 11:57 AM

I know that if you leave static images on a rear projection tv for extended lengths of time this can cause the image to be permanently "burnt" into the screen. What I want to know is, if you watch alot of widescreen movies in letterbox format, will there be two bars burnt into the top and bottom of the screen?

Tight Git · 15-12-2004, 1:23 PM

Quote:

Originally Posted by blue_harvester

I know that if you leave static images on a rear projection tv for extended lengths of time this can cause the image to be permanently "burnt" into the screen. What I want to know is, if you watch alot of widescreen movies in letterbox format, will there be two bars burnt into the top and bottom of the screen?

Yes, it's exactly the same issue as with on screen logos etc.

But, as with on screen logos, you'll have to watch an awful lot of widescreen films at high contrast to see the effect.

(If you stick to widescreen films, it won't matter anyway!)

**alexs2** · 15-12-2004, 1:28 PM

Had ours for a couple of years now,and no problems with screen burn of any type.

blue_harvester · 15-12-2004, 2:45 PM

Thanks for the reply guys. Yeah I suppose if I stick to widescreen movies it won't matter. By the way, how long do Rear Projection TVs generally last? I mean is there a certain life span for the internal bulbs like normal projectors?

Tight Git · 15-12-2004, 4:32 PM

What type of RP are we talking about?

When I made my original comments(above) I assumed CRT, but now you mention bulbs.

**alexs2** · 15-12-2004, 4:35 PM

DLP and LCD RPTV's will of course not be susceptible to screen burn,whereas a CRT based one has tube life,and screen burn to contend with,as possible hazards,and many folks translate CRT life into bulbs when discussing CRT based RPTV's as well.

Tight Git · 15-12-2004, 7:17 PM

Quote:

Originally Posted by alexs2

... many folks translate CRT life into bulbs when discussing CRT based RPTV's ...

Assuming that's correct in this case:

Blue Harvester,

CRT's in a projection system (front or rear) are run very hard and are generally reckoned to have a useful life of about 10,000 hours.

That translates to one film a night for about 10 years.

Not too bad, although you do say you watch a lot of movies!

The real problem is if one tube fails after, say, 5,000 hours.

You may well have to replace all three (at £400 each) in order to get a good colour balance.

Hope this hasn't spoiled your Christmas!

**alexs2** · 15-12-2004, 7:21 PM

Quote:

Originally Posted by Tight Git

Assuming that's correct in this case:

Blue Harvester,

CRT's in a projection system (front or rear) are run very hard and are generally reckoned to have a useful life of about 10,000 hours.

That translates to one film a night for about 10 years.

Not too bad, although you do say you watch a lot of movies!

The real problem is if one tube fails after, say, 5,000 hours.

You may well have to replace all three (at £400 each) in order to get a good colour balance.

Hope this hasn't spoiled your Christmas!

Thats absolutely right,but I think it's a factor you have to take into account when buying a projection system of whatever type in that bulbs or tubes can be very expensive to replace,and certainly bulbs for DLP or LCD systems can be pretty short-lived as well as quite costly.

GagHalfrunt · 16-12-2004, 1:49 PM

What this comes down to though is setup.

If you use Avia or whatever to set the picture up when you first get it I don't see this being a problem. It's only because people leave the contrast set too high. Also never leave the EPG or whatever on the screen all the time.

condyk · 16-12-2004, 7:42 PM

Quote:

Originally Posted by GagHalfrunt

What this comes down to though is setup.

If you use Avia or whatever to set the picture up when you first get it I don't see this being a problem.

What is Avia? I have a new RPTV arriving tomnorrow and want to set it up so it has a great picture and lasts as long as possible without screen burn or failed bulbs (well, 2-3 years anyway!)

condyk · 17-12-2004, 8:11 AM

Quote:

Originally Posted by condyk

What is Avia? I have a new RPTV arriving tomnorrow and want to set it up so it has a great picture and lasts as long as possible without screen burn or failed bulbs (well, 2-3 years anyway!)

Don't worry, I searched around and found out what it was. Just what I need I reckon and so a copy ordered. Delivery 10 days or so. Will give time for TV to settle down.

blue_harvester · 17-12-2004, 10:24 AM

Well is there any best practice when using Rear Projection systems like leaving the TV on standby etc. to prolong the life of the set?

runningback · 17-12-2004, 10:32 AM

generally speaking lower settings=longer tv life, especially contrast and brightness.

**alexs2** · 17-12-2004, 10:46 AM

Quote:

Originally Posted by runningback

generally speaking lower settings=longer tv life, especially contrast and brightness.

very true,especially considering the default values that most of the manufacturers seem to have the TV's set to for delivery...mine was at 100% for brightness,sharpness and contrast,and is now at around 50% for all of those values,so well worth spending some time adjusting the picture until it's watchable in an ordinary house.

Tight Git · 17-12-2004, 11:14 AM

Quote:

Originally Posted by alexs2

very true,especially considering the default values that most of the manufacturers seem to have the TV's set to for delivery...mine was at 100% for brightness,sharpness and contrast,and is now at around 50% for all of those values,so well worth spending some time adjusting the picture until it's watchable in an ordinary house.

Some manufacturers set the defaults high so that the set will stand out from others if the shop puts it on display.

Not good practice technically, but you can't really blame them.

That's why the more knowledgeable viewer (= Forum member

) immediately adjusts all the settings to a more reasonable level.

**alexs2** · 17-12-2004, 11:17 AM

Quote:

Originally Posted by Tight Git

Some manufacturers set the defaults high so that the set will stand out from others if the shop puts it on display.

Not good practice technically, but you can't really blame them.

That's why the more knowledgeable viewer (= Forum member

) immediately adjusts all the settings to a more reasonable level.

Exactly my point...saves the retailer doing anything to it when putting one on display,but leads to severe eye-ache within minutes in an ordinary room....and also earache from one's wife who sees new 50"RPTV and immediately declares it to be unwatchable....

GagHalfrunt · 17-12-2004, 1:49 PM

Not only that, but the picture will look far more natural when you've "fixed" it. Mine did.