Touch are looks smaller then the LCD size

Continuing the discussion from OctoScreen - a new software to use OctoPrint with LCD:

Hi, OctoScreenis runs fine on my pi 3 with a 5" LCD ( HDMI Interface 5 Inch 800x480 TFT Display - Elecrow), but the only thing is that the touch looks not correct calibrated in OctoScreen, it looks like the touch area are smaller then the lcd.
I have installed the configuration utility and created the file "99-calibration.conf" with my calibration result:

Section "InputClass"
        Identifier      "calibration"
        MatchProduct    "ADS7846 Touchscreen"
        Option  "MinX"  "19108"
        Option  "MaxX"  "19271"
        Option  "MinY"  "53771"
        Option  "MaxY"  "52860"
        Option  "SwapXY"        "1" # unless it was already set to 1
        Option  "InvertX"       "0"  # unless it was already set
        Option  "InvertY"       "0"  # unless it was already set
EndSection

The Resolution in the conifg.txt is set tp 800x480 and looks all fine....

Anyone a idea what wrong with it?