Yellow tint picture is yellow in middle - Panasonic PT-50LC13 50" Rear Projection HDTV

Jerry to be frank with you I would not invest another cent in that Tv. The new once are getting cheaper and you would be alot happier. If you do decide to purchase a new TV look for SMART TV'S. Good Luck.

Is it an LCD tv or CRT ?
If CRT try moving the TV to a different location as the magnetic field from another device or even the earth can effect it.
The power switch (full power on) would normally demagnetise the screen.
If its an LCD has any object hit the screen, it could be a child's toy or knocking the screen can bruise the panel.

i have a yellow cricle on the middle of my screen how do i fix it

I don't know if this set is a DLP or not, if it is, it could be your light engine. Not good, mine had a yellow halo about 2in thick in the middle of the screen. Light engine had to be replaced. Hope this is helpful. GOOD LUCK!

in night shot mode always greenish yellow tint ahead. it 's common

you can adjust in color mode. please balance the tint, color,brightness, contrast, & sharpness.

Yes, It could be either your video board or your dmd board, go to the service menu and if the yellow tint is still there, it's your dmd board, if not it will be your video board

Sounds like the color wheel has gone bad and needs to be replaced. This is located behind the back panel.

Replaced cable and the problem was solved.

Colorimetre HCFR software
AVC HD 709 calibration disk
Spyder2 colorimeter (I know most prefer the Eye-One meters, but the Spyder2 was available from my job at no cost)

Here are the settings:

PS3 Blu-Ray player

Output Format (HDMI): Y Pb/Cb Pr/Cr (important!!! NOT RGB output)
BD 1080p 24hz Output (HDMI): On (this TV can reproduce video at 48hz for accurate 2:2 pulldown)
Y Pb/Cb Pr/Cr Super White (HDMI): On (not sure if this matters)

42LG50 Settings

Aspect Ratio: Set By Program (Personal Preference)
Picture Mode: Expert 1
Backlight: 50 (Personal Preference)
Contrast: 54
Brightness: 54
Sharpness: 40 (Personal Preference)
Color: 50
Tint: 0

Fresh Contrast: Off
Noise Reduction: Off
Gamma: Medium
Black Level: Low
Real Cinema: On

White Balance: Warm
Method: 10 Point IRE

10 (-3,8,-16)
20 (15,24,-21)
30 (20,36,-22)
40 (3,19,-40)
50 (8,34,-41)
60 (10,50,-20)
70 (-5,50,-8)
80 (-16,50,18
90 (-14,50,30)
100 (-22,38,21)

Red Color: -3
Red Tint: 0
Green Color: 10
Green Tint: 0
Blue Color: 14
Blue Tint: 0
Yellow Color: 0
Yellow Tint: 1
Cyan Color: -11
Cyan Tint: 0
Magenta Color: 0
Magenta Tint: -2

Take time to get used to the settings, you may think the screen looks dull at first. The truth is most people have way too much contrast on their TVs.
These settings will also work for Cable or Dish hookups, in which case you may change the Noise Reduction option to Medium to reduce signal noise.

OR....

2POINT IRE

Backlight: 65
Contrast: 55
Brightness: 45
Sharpness: 50
Color: 45
Tint: 0

Fresh Contrast: Off
Noise Reduction: Off
Gamma: Medium
Black Level: Low
Real Cinema: On

White Balance: Warm
Method: 2 Point

Red Color: 3
Red Tint: 0
Green Color: 9
Green Tint: 2
Blue Color: -1
Blue Tint: 0
Yellow Color: 6
Yellow Tint: 5
Cyan Color: -1
Cyan Tint: 1
Magenta Color: 2
Magenta Tint: -1