LN52A550P3FXZA / LN37A550P3FXZA display issue

[captainKKK]

I have both LN52A550P3FXZA and LN37A550P3FXZA units that have had their C131 and C102 capacitors replaced on the main boards and they both work as they should, except the whites are much whiter in the 37 ( I bot new) vs the 52" (donated to me). The 37" has the 1005.1 and 1006.1 firmware and the 52" came with the 1007.1 firmware. I cannot find the 1007.1 download source. I am hesitant to try to overwrite the 1007.1 FW. I have factory reset the 52" and the service menu values of both are the same. I have tweaked the video settings (and gamma) every way I can w/o any success. Is it possible that bad caps on the PS could make the 52" whites look slightly brown or could the firmware version make this difference.? Is it possible the 52" has the wrong firmware installed? My pictures here make the 37" look washed out but trust me it is not and it displays brilliant, as good as any LED unit. I want the 52" to display like the 37". The 37" had its t-con previously replaced, I do not know the 52" history. Any ideas?

[dskall]

Re: LN52A550P3FXZA / LN37A550P3FXZA display issue

Looks like a contrast issue.

[captainKKK]

Re: LN52A550P3FXZA / LN37A550P3FXZA display issue

Look at the second pic after I tweaked the 52". Its not the brightness / contrast of the 52....I dialed the BL up and down, along with contrast and brightness and even adjusted the gamma but still the whites are just not white. After tweaking from the service menu so much, it would not let me turn the back lights below 5 and it would black screen but keep audio going. I had to do a WB reset, then an EER reset, then a Factory reset to get back to normal. If the 37" was not sitting next to it, I probably would not complain about the 52" white issue. Just trying to see if someone had a component issue with this. When I had white screens on both the 52 had two 12" tan horizontal circles from the backlights.....do LCD backlights go very light tan when they get old? Or could the 52" have lived it life in a smoker's home?

[dskall]

Re: LN52A550P3FXZA / LN37A550P3FXZA display issue

To me the top picture looks the best. Bottom looks washed out.

[captainKKK]

Re: LN52A550P3FXZA / LN37A550P3FXZA display issue

Thanks dskall for your input. Do LCD tubes ever degrade, thus showing off white? Think of my issue as comparing 5000k LED vs incandescent lights. Could the 52" have an LCD inverter issue? I have always thought of LCD tubes as either good on bad. In this attached pic, particularly evident on the left side, horizontally in the middle, I can see a light tan area under the words "Log does not exist". This screen should be pure white but appears with light tan splotches. Is this a defect, degradation or something that can be addressed? My 32" does not do this.

[Biruslapio]

Re: LN52A550P3FXZA / LN37A550P3FXZA display issue

I have some pics from 2019, a Samsung LN46A550P3R showing LCD panel aging, the corners get a different shade, and it goes around the entire screen, this is common and can be spotted on a lot of old LCDs, sometimes when they go defective these marks appear too.

The brightness was exaggerated to show how bad the black uniformity is, and in the other image the corners are darker on a static display. Since the LNXXA series are from 2008, it's only natural that it is not like new, the lamps age too and the edges get darker.

In these pictures compating the 37 and 52 inch variants, the camera captured the 52 inch image as being more natural, the 37 looks too bright, like bad gamma, it might just be the 37 inch backlight being brighter.

[captainKKK]

Re: LN52A550P3FXZA / LN37A550P3FXZA display issue

Biruslapio, thanks for your input. Since I am the original purchaser of the 37", I know its backlight feature was turned off all the time. Maybe that explains why it is much brighter and whiter. At any rate, I cracked open the 52" and could not tell any LCD different lighting from the LCD tubes when they were on. I inspected the diffuser sheets and found no transparency issues. It could be the different required "LVDS Output Format" in my first post pictures, in the Service Menu settings. Maybe the the JEIDA vs PDP formats produce different whiteness levels. If I change those, it inverts the colors and therefore those must be as set for each different LVDS. At any rate, at least now, I know the LCDs are sufficient and the diffuser sheets are not dirty or decayed.

[dskall]

Re: LN52A550P3FXZA / LN37A550P3FXZA display issue

So these are fluorescents. They do age and turn more reddish as they age.

[captainKKK]

Re: LN52A550P3FXZA / LN37A550P3FXZA display issue

LCD TVs must have longer life than LEDs Pictured are made in 2008. I always thought fluorescents were LCDs

[dskall]

Re: LN52A550P3FXZA / LN37A550P3FXZA display issue

Both are LCD tv's. The older are lit with ccfl and newer are lit with led's. Theoretically led's should last longer. Ccfl's wear out.