Dim nRed As Long, nGreen As Long, nBlue As Long, nWert As Long
 
nRed = PCol Mod 256
nGreen = ((PCol And &HFF00) / 256&) Mod 256&
nBlue = (PCol And &HFF0000) / 65536
nWert = (nRed + nGreen + nBlue) / 3
 
PCol = RGB(nWert, 0, 0)

Dim nRed As Long, nGreen As Long, nBlue As Long, nWert As Double
Dim newRed As Long, newGreen As Long, newBlue As Long
 
newRed = newColor Mod 256
newGreen = ((newColor And &HFF00) / 256&) Mod 256&
newBlue = (newColor And &HFF0000) / 65536
...
For ...
    ...
    nWert = (nRed + nGreen + nBlue) / (3 * 255)
    PCol = RGB(nWert * newRed + nWert * newGreen + nWert * newBlue)
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