[rockadanny]

Got new plasma - right out of the box picture looks great, but am scheduled for ISF calibration in few weeks. During this time I am supposed to break in the screen, playing 100-200 hrs. I watch about 4 hrs. of TV per week so will just fire it up each morning I work from home and let it run all day. I figure a full screen picture (not letter box) with no channel logo would be best to avoid any potential burn in issues prior to calibration. BUT, not many full screen channels, and I never noticed this before with my 22" tube TV from 12' away, seems every stupid channel (Comcast - around 100 channels from which to choose) has a logo pasted on it in the lower right corner of the picture. It disappears but only for commercials. Others have some sort of stupid banner pasted somewhere as well.

For prolonged TV power on during break in:
1. Is it necessary to avoid letter box picture?
2. Is it necessary to avoid channel logos?

[Crimson]

1. Yes
2. No

I say yes to number one only because you want the entire screen active, not because of any image retention issues. Plasmas have come a long way and I wouldn't worry about image retention.

[mcgsxr]

In order to avoid 1, and possibly 2, you could just ZOOM the aspect ratio, and fill the screen.

[WerTicus]

Burn in does not exist anymore outside of crazy hours of abuse.

If you watch letter boxed content the image retention you see is actually just panel age being different due to the exponential burn in process.  After the 100hrs you wont see this anymore.

If its a Panasonic its pretty bullet proof, ie 2 hrs of burning  = 2mins of full screen content and its gone... 

Samsung less bullet proof but it has IR removal tools in the menu.

An aged Panasonic requires more than 5 hrs of cooking to get any IR that last more than 30 seconds.  (which would only be visible on a blank screen anyway)

[Dan Driscoll]

You could also loop a DVD or BRD. As mcgsxr suggested, zoom to fill the screen and exercise all the cells.