Red color lost in my tab 10.5 I have a Samsung tab s 10.5 inch. Once I try the Samsung code *#0*# and try to check the red color it gives a black screen, but all other color tests working fine – even tab working fine but any red color showing black  in all pics. I went to Samsung, they told problems is in Lcd or digitizer.

Any one can help please?
If the test is not displaying any red this is your LCD (all colors are created using 3 LED (light emitting Diodes) Red Green Blue (RGB)  Sadly your R is DEAD.  It might be something as simple as a loose correction which a technician with a test kit and some soldering could fix.

But I doubt you could do it yourself sorry to say.  Find a good computer repair shop near you.... Or contact Samsung and find an "authorized" repair shop if you are wonder warranty.

Good LUCK!