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Discussion Starter #1
Better in person
 

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That looks pretty darn useable to me. Looks like you can see a bit of wear on the right side. I'm guessing maybe 4000 hours of use? the rest of the hours were put on while the set was not projecting light.


Curt
 

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Discussion Starter #4
Quote:
Originally posted by Curt Palme
That looks pretty darn useable to me. Looks like you can see a bit of wear on the right side. I'm guessing maybe 4000 hours of use? the rest of the hours were put on while the set was not projecting light.


Curt
Tonight Ill try and get a shot of just the white test screen - it will clearly show wear on both sides.
 

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No one is doubting the wear is there, and yup it will look worst on a white screen, but you won't normally see it on screen - well maybe in Ice-age or 2001 :)

Anyhow, if it bugs you, work within the wear, otherwise, just set it up baby, it looks A-OK to us. (Or hock it to me for 400 bucks:)
 

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Try watching Fargo on it .


When I first got my pj, I watched Fargo and the spread sheet bar graphs looked real "nice" in the snow...
 

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If you're running an HTPC, you can create a negative burn mask with PhotoShop (and a good digital camera) and use that mask to even out the response. Reports from those who are experimenting with it are that it can work EXTREMELY well, to the point that a pretty well burned CRT can still throw a picture that has NO visible burns or shadows even on a white screen.


It can even be used like multizone contrast modulation as well.


I would like to experiment with it myself, but I don't have PhotoShop and my HTPC is a primitive little thing that would choke on the workload. I guess it's enough that a Celeron 300 can even work well as a DVD player.


CJ
 

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A celeron 300 will happily run an imaging program to create a mask.

You could use a trial version of paintshop pro
 

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Discussion Starter #9
Quote:
Originally posted by cmjohnson
If you're running an HTPC, you can create a negative burn mask with PhotoShop (and a good digital camera) and use that mask to even out the response. Reports from those who are experimenting with it are that it can work EXTREMELY well, to the point that a pretty well burned CRT can still throw a picture that has NO visible burns or shadows even on a white screen.


It can even be used like multizone contrast modulation as well.


I would like to experiment with it myself, but I don't have PhotoShop and my HTPC is a primitive little thing that would choke on the workload. I guess it's enough that a Celeron 300 can even work well as a DVD player.


CJ
That sounds interesting - but how do I compensate for the missing picture under the mask - wouldnt I be cropping out movie information?
 

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look at it this way, you have a crt with 4:3 wear.

i.e. a big patch of your tube displays dim, and a border around it displays somewhat brighter.

This gives you a visible 'border' when displaying an image on screen.


There are 4 ways to tackle it.


1) adjust the picture on the tube so that the whole thing fits within the 'dim' square. this way, the whole picture is displayed only in the dim part, so you don't have any border to see. (i.e. the bright 'border' is unused). Downside - using much less raster, dimmer and smaller image with less resolvable resolution.


2) Try to burn the untarnished bright border around the 4:3 square until it is just as dim as the 4:3 square itself. Then you can display the image on the full size of the tube, as the whole thing is now dimmer (i.e. the wear is now universal).

How? Display a bright white image that exactly matches the border, with black in the area of 4:3 wear. Downside:If you get it wrong, you may end up with an even worse looking border, you also are running up a lot more hours, and I can't see how you could even out 6000 hours of wear without having to put a few thousand more hours into burning out the border. Some members have nuked their tube trying.


3) Use a system that effectively displays a 'watermark' on your projector in the shape of the brighter border so that when you play movies, the border are is dimmed to about the same level as the 4:3 square making the border effect disappear. Downside: No-one has made the software filter to do this yet...I'm workin on it.


4) Buy new tubes.


Or you can always ignore the wear and enjoy the movies.
 

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 http://www.avsforum.com/avs-vb/showt...47#post3246447


It looks like this HAS been successfully implemented, as evidenced by this thread!



The idea is very simple: Take a photo of your screen showing a full white field, and all its burns and flaws. Make a negative of that photo, make a mask of it, and superimpose that mask on your projector's output, all digitally. Some adjustments to the brightness and contrast of the mask will of course be necessary, as will proper registration of the mask and also of course proper sizing.


The mask is going to have the effect of reducing the brightness of your image in all unburned areas to the same brightness as the burned areas.


OR....it will drive the burned areas harder to make them keep up. I would NOT recommend this approach! The subtractive approach is better.


The tricky part is that the mask will only be accurately aligned and shaped if it's taken from a perfectly aligned projector. Changes in the alignment will result in mask inaccuracies.


In a sense, the mask is a full-screen watermark that looks exactly like the screen burn, but as a negative of it.


Ideally, you'd make separate masks for red, green, and blue, individually, for the greatest precision.


I'm sure my C300 can run PhotoShop, what I'm not sure of is that it has the horsepower to run a mask AND play a DVD at the same time without performance issues. It's a fact that it can't quite manage that trick with Zoom Player alone. I have to watch movies on that with Cyberlink's PowerDVD, not Zoom Player, due to that performance issue. Zoom uses up more available processing power than the C300 can provide on a sustained basis.


CJ
 

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This is unwatchable. I can't believe you guys are talking about burn in. If this is the best you can get this sell it and buy a RPTV. If anyones CRT projector looks like this you need help. IMO.
 

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"This is unwatchable."


LOL! Hardly! Considering it's not converged, it looks like it should work great, just work in from that worn edge, and you're good to go!
 

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Discussion Starter #15
Quote:
Originally posted by RODDMOD
This is unwatchable. I can't believe you guys are talking about burn in. If this is the best you can get this sell it and buy a RPTV. If anyones CRT projector looks like this you need help. IMO.
Read over the posts again.


I drove home and placed it on a block of wood till it looked "about" focused on a wall half paneled.


Considering its not setup or doubled and tweaked I would say your a bit off base..the RPTV is up for sale at Ebay if you want one so bad.
 
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