Problem with GetPixel - help please

[WarrenW]

The routine I have below I want to get the pixel of the screen. It returns nothing here. If I move the GetPixel call out of the loop, it returns something.

Any idea what I'm doing wrong or a better way of this?

Thanks!

Private Sub Command1_Click()
Dim hDC As Long
Dim H1 As Long
Dim W1 As Long
Dim Z As Long
  H1 = Screen.Height / Screen.TwipsPerPixelY
  W1 = Screen.Width / Screen.TwipsPerPixelX
  Dim X As Long
  Dim Y As Long
  hDC = GetDC(0) 'get desktop dc
  
  For Y = 1 To Y1 - 10
    For X = 1 To H1 - 10
      
      Z = GetPixel(hDC, X, Y)
      Memo1.Text = Memo1.Text & Trim(Str(Z))
      
    Next X
  Next Y
 
End Sub