Hi Hank,

Not sure if this will help but I created an Excel spreadsheet that charted the gamma "duty cycle" values generated by the "anti-log" formula in that simple JustBASIC program I use for generating the anti-log gamma tables. Here's what the Excel chart looks like;

Name: gamma chart.png Views: 2898 Size: 41.4 KB

And if you've forgotten, here's the program I use for generating the gamma brightness level correction tables (using the free JustBASIC program as well as an example of the output window;

Code:
 '  Leo Bodnar's 'antilogarithmic'
 '  gamma correction algorithm (Mike, K8LH)
 '
 '  JustBASIC (free) interpreter
 '
 Input "Gamma array size: "; arraysize
 Input " Total PWM steps: "; width
 Input "Gamma correction: "; gamma       ' try 0.5 to 1.0
 Input "Entries per line: "; entries     '

 FOR index = 0 to arraysize-1
    dcyval = INT(width^(((index+1)/arraysize)^gamma)+.3)
    if(index = 0) then
      dcyval = 0
      PRINT
      PRINT "  DW ";
    else
      if(index MOD entries = 0) then
        PRINT ","
        PRINT "  DW ";
      else
        PRINT ",";
      end if
    end if
    if(dcyval < 100) then print " ";
    if(dcyval < 10) then print " ";
    PRINT dcyval;
 NEXT index
 PRINT
 PRINT
 REM CLOSE
Code:
Gamma array size: 100
 Total PWM steps: 512
Gamma correction: .55
Entries per line: 10

  DW   0,  2,  2,  3,  3,  4,  4,  5,  5,  6,
  DW   6,  7,  7,  8,  9, 10, 10, 11, 12, 13,
  DW  14, 15, 16, 17, 18, 19, 21, 22, 23, 25,
  DW  26, 28, 29, 31, 33, 35, 37, 39, 41, 43,
  DW  45, 48, 50, 53, 56, 58, 61, 64, 67, 71,
  DW  74, 78, 81, 85, 89, 93, 97,102,106,111,
  DW 116,121,126,132,137,143,149,155,162,168,
  DW 175,182,190,197,205,213,222,231,240,249,
  DW 258,268,279,289,300,311,323,335,347,360,
  DW 373,387,401,415,430,446,461,478,494,512
Good luck on your project.

Cheerful regards, Mike