All posts by Dianne
Below are all of Dianne's postings, with the most recent are at the bottom of the page.
So the BBC are saying 'don't leave the Test Card on for longer than a specific period of time' - what about all those station logos etc that we have to contend with, then? Why can't they be disabled by pressing the green button on the remote control - like the Red "Press" which brings up the BBC Teletext can - in order to reduce the possibility of a burn-in? In LCDs, burn-in can develop because pixels permanently lose their ability to return to a relaxed state after displaying a static image for a prolonged period, as this BBC recommendation confirms.
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Brian:
I believe it was a widespread myth for a while that transmissive displays like LCD weren't subject to burn-in - or rather image persistence, as it should more accurately be described - but in my view it would really be more precise to say that they are less subject to burn-in, as the words on the whole in the last line of your kind response imply.
The effect with LCD displays is similar in appearance to CRT burn-in and is the result of the constant voltage produced by a static image causing the crystal voltage-response curve to change, which results in them letting more (or less) backlight through when compared with surrounding pixels. OK, technically its not burn-in but the effect, which can occur after just a few hours, is very similar.
There are several things you can do to effect some sort of cure for image persistence (just Google!) but at the end of the day prevention is better. Whilst screen dimming will help reduce burn-in with the old CRT displays, dimming or darkening an LCD backlight won't help preserve your pixels!
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I cannot for the life of me see the necessity for DOGs. On most if not all modern television receivers the channel, details of the current broadcast, date and time are displayed along the bottom of your screen each time you select a new programme. I find some of the larger and brighter graphics intrusive and take my hat off to Film Four, who thus far seem to have resisted the temptation to include a DOG.
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Saturday 11 August 2012 9:04PM
I live in Sutton-in-Ashfield, Nottinghamshire but my Samsung TV receives a Freeview signal from Yorkshire TV. I would like to watch Central ITV from the Waltham transmitter, which can also be received in this area but am not sure of the re-tuning process. Also, when you have settled on an ITV station, how can you tell which one it is? Pressing the Info button brings up programme information and other things - but doesn't tell you what ITV company you are watching! (ie Yorkshire, Central, Meridian - or what?)As I would like to receive Central for its local news output and as at most other times of the day programmes are the same from region-to-region, how can I tell whether my re-tune has been successful?