I have an image which contains a color: 3F, 45, 61

As this is not a fixed color, I have to enter those values manually in the color picker in VFP. So, I use the BackColor color picker button to obtain the panel. In that panel, I can define a custom color. Once in it, I can enter the value. However, in there, I can't enter a letter. The first color pair is 3F. How would I go about that?