Panasonic TH-42PA50E Operating Instructions Manual page 22

Aspect Controls
16 : 9
16:9 will display a true 16:9 (anamorphic) picture with no aspect distortions.
14 : 9
14:9 will display a 14:9 picture at its standard 14:9 size without any
stretching.
Just
Use Just when you wish to expand a 4:3 picture to fi ll the whole screen (rather
than watching a programme with black stripes down the left and right sides of
the picture).
The 4:3 picture will be stretched horizontally so that the image fi lls the screen,
this is done in such a way that the stretching is only obvious at the left and
right edges of the screen.
4 : 3
4:3 will display a 4:3 picture at its standard 4:3 size with no aspect
distortions.
Zoom1
Zoom1 will display 16:9 letterbox or 4:3 pictures with no aspect distortions.
Zoom2
Zoom2 will display 16:9 anamorphic letterbox pictures as a full screen display
with no aspect distortions.
Zoom3
Zoom3 will display 21:9 letterbox pictures as a full screen display with no
aspect distortions.
16:9 will display the picture at its maximum size but with slight stretching.
22
16 : 9
16 : 9
14 : 9
14 : 9
Just
Just
4 : 3
4 : 3
Zoom1
Zoom1
Zoom2
Zoom2
Zoom3
Zoom3