TI-89 titanium screen is DARKER than the ti-92+ screen WHY ?

[Brados]

Hello everyone

I have just bought a ti-89 titanium Today
It works fine everything is OK but...

I compared the screen of the ti-89 titanium with my old and lovely ti-92+ and...
The Ti-89 titanium has a DARKER SCREEN than my ti-92+!!!
the ti-92+ screen seems really brighter than the ti-89 titanium screen.

This makes no sense to me, since the ti-89 titanium is newer than the ti-92 plus.

Is the titanium version which have this problem of dark screen ? or all of them.
If it is the case I can return it and buy the standard ti-89.
I tried to replace the batteries and adjust the contrast up and down but this is not the issue.
When both ti-89 titanium and ti-92+ are turned off. The ti-92+ screen seems more white than the ti 89-titanium and it is brighter !!

If this is normal why TEXAS INSTRUMENT has chosen to put that screen in the 89 titanium since there is a better screen to put there weird !

I have hardware Version 4 (HW4)

Thank you for your help