Dazmax
Hi all
Picking up on a comment made in another post, refering to screen burn in, I thought this information could be usefull.
Screen burn occurs when a static graphic or image is displayed on some types of screen for extended times. Static images can damage the light emitting surfaces on CRT Tv's/projectors and produce uneven light output from Plasma screens. The effect causes the burned image to be visible after the graphic is no longer being projected. Once the damage is done it is not repairable. The systems which are sensitive to this are CRT type projection screen setups and also Plasma displays.
CRT projectors can be identified by the three Red Green and Blue lenses/tubes visible at the front of the unit and are usualy much larger than all other projector types. CRT projectors are very sensitive to screen burn in and for safety try to avoid the display of static logos, pictures or other graphics for more than 15mins at any time. If you are using graphics try to animate the graphic in some way. With logos try to move the logo around to a different area of the screen every 5 min or so. Even displaying video content that has an aspect ratio which is not covering the screen (black bars at top and bottom) can damage these projectors over time so try and maximize the picture to avoid this.
Plasma screens are also sensitive to screen burn in, but will tolerate longer periods than CRT projectors and dont tend to suffer from burn in caused by the black bars. The above precautions still apply.
LCD screens, DLP, DLA and LCD projectors do not suffer from this problem.
I work with large multi projector visual systems on flight simulators and have also spent time working on CRT systems used in Pubs and Clubs. The look on a club owners face when you tell them that the projector that cost them anything up to 25 grand needs a 10 grand re tube is not one you want to be responsible for.
Hope this helps
Daz
Picking up on a comment made in another post, refering to screen burn in, I thought this information could be usefull.
Screen burn occurs when a static graphic or image is displayed on some types of screen for extended times. Static images can damage the light emitting surfaces on CRT Tv's/projectors and produce uneven light output from Plasma screens. The effect causes the burned image to be visible after the graphic is no longer being projected. Once the damage is done it is not repairable. The systems which are sensitive to this are CRT type projection screen setups and also Plasma displays.
CRT projectors can be identified by the three Red Green and Blue lenses/tubes visible at the front of the unit and are usualy much larger than all other projector types. CRT projectors are very sensitive to screen burn in and for safety try to avoid the display of static logos, pictures or other graphics for more than 15mins at any time. If you are using graphics try to animate the graphic in some way. With logos try to move the logo around to a different area of the screen every 5 min or so. Even displaying video content that has an aspect ratio which is not covering the screen (black bars at top and bottom) can damage these projectors over time so try and maximize the picture to avoid this.
Plasma screens are also sensitive to screen burn in, but will tolerate longer periods than CRT projectors and dont tend to suffer from burn in caused by the black bars. The above precautions still apply.
LCD screens, DLP, DLA and LCD projectors do not suffer from this problem.
I work with large multi projector visual systems on flight simulators and have also spent time working on CRT systems used in Pubs and Clubs. The look on a club owners face when you tell them that the projector that cost them anything up to 25 grand needs a 10 grand re tube is not one you want to be responsible for.
Hope this helps
Daz
Inviato Mon 15 Jun 09 @ 1:55 am
leighfromnz
Just think of the exposure though - your logo etched forever on the clubs projector ;)
Inviato Mon 15 Jun 09 @ 3:06 am
Dazmax
Just goes to show.
THERE IS ALWAYS ONE. lol
The disadvantage is that the club owner will know who to send the repair bill to.
Daz
THERE IS ALWAYS ONE. lol
The disadvantage is that the club owner will know who to send the repair bill to.
Daz
Inviato Mon 15 Jun 09 @ 3:47 am
tayla
a logo hiding a logo, seems to me the real reason why anyone wants to stick them on the screen for any length of time...
Inviato Mon 15 Jun 09 @ 3:53 am
SBDJ
Some displays have burn in protection which can help, picture shifting is quite common now for example...
Inviato Mon 15 Jun 09 @ 5:09 am
juist use a slideshow of me for uplifting images that kick burn in right in the face
Inviato Mon 15 Jun 09 @ 7:56 am
Dazmax
Yeh, apart from that one you did with the thong and the nipple tassels. That one stays under lock and key for future bribery purposes Chuck.
Daz
Daz
Inviato Mon 15 Jun 09 @ 11:34 am
Andrew87
SBDJ wrote :
Some displays have burn in protection which can help, picture shifting is quite common now for example...
I'm not sure whether the tv companies do this (and therefore it may be useful as a virtual dj plugin) but shifting can be done before being output to the display? E.g. alternating the colour slightly and shifting the image around a few pixels but discretely where it's not apparent to the viewer.
Inviato Mon 15 Jun 09 @ 11:47 am
SBDJ
A lot of manufacturing companies do that sort of thing, a tiny shift in the output that isn't generally noticeable - although if you've got a box on the screen and nothing else you can often see it jump slightly lol...
A tiny position shift (say a pixel or two) would be easily managable in a plugin through a simple vertex modification - a couple of minutes work. The problem of course is how far do you shift to cope with similar adjacent pixels - far example a single colour logo.
A tiny position shift (say a pixel or two) would be easily managable in a plugin through a simple vertex modification - a couple of minutes work. The problem of course is how far do you shift to cope with similar adjacent pixels - far example a single colour logo.
Inviato Mon 15 Jun 09 @ 12:03 pm
Dazmax
One of the things you can look at is to use an animated logo which alternates the colours of your logo between red green and blue. This will reduce the time that the logo is displayed on any one tube without you having to move the logo around so often. Watch out for CDG discs that have static logos. If you are using the same make of disc ie Sunfly try not to leave the track displayed on pause for extended time. You could use animations in between Karaoke tracks.
Daz
Daz
Inviato Mon 15 Jun 09 @ 12:26 pm
Tim Bennett
I've installed LCDs and plasmas for bank reception areas, Chamber of Commerce buildings and convention centers and image shift has never prevented burn-in. It may delay it but it will come.
Inviato Mon 15 Jun 09 @ 1:49 pm
Dazmax
I am no expert on Plasma but can confirm that image shifting (on a pixel by pixel basis) with CRT systems just gives you a bigger burned area on the tube.
CRT projector tubes don't function on a pixel basis (although the projectors take digital inputs). The picture is scanned onto a light emitting phosphor coating. This is on the inner surface of the tube face, or on some larger units, a metal target mounted inside the tube. An electron beam is scanned across the phosphor and modulated as it is scanned. The scanning is done on a line by line basis to build up the picture. If a fixed picture is displayed the phosphor in the bright areas of the picture is burned off and stops producing light when it is scanned over.
Any static picture on a CRT system will cause burn in very rapidly.
Plasma displays are made from a large number of tiny cells each containing a gas mixture which emits light relevent to the colour of the cell As with CRT projectors 3 coloured cells are used Red Green and Blue. Each cell has a limited operating life and with normal moving video the light output deteriorates at more or less the same rate in all the cells. This reduces the screens ability to produce a high brighteness picture but only over a very long period of time so it is not normaly noticed. When a fixed picture is displayed the cells producing the greatest light output will fail more rapidly and voila you have a burned image on the screen.
Daz
CRT projector tubes don't function on a pixel basis (although the projectors take digital inputs). The picture is scanned onto a light emitting phosphor coating. This is on the inner surface of the tube face, or on some larger units, a metal target mounted inside the tube. An electron beam is scanned across the phosphor and modulated as it is scanned. The scanning is done on a line by line basis to build up the picture. If a fixed picture is displayed the phosphor in the bright areas of the picture is burned off and stops producing light when it is scanned over.
Any static picture on a CRT system will cause burn in very rapidly.
Plasma displays are made from a large number of tiny cells each containing a gas mixture which emits light relevent to the colour of the cell As with CRT projectors 3 coloured cells are used Red Green and Blue. Each cell has a limited operating life and with normal moving video the light output deteriorates at more or less the same rate in all the cells. This reduces the screens ability to produce a high brighteness picture but only over a very long period of time so it is not normaly noticed. When a fixed picture is displayed the cells producing the greatest light output will fail more rapidly and voila you have a burned image on the screen.
Daz
Inviato Mon 15 Jun 09 @ 2:52 pm