B-V to Kelvin formula

Posted by PeanutPower on Stack Overflow See other posts from Stack Overflow or by PeanutPower
Published on 2010-03-11T17:11:49Z Indexed on 2010/03/11 17:19 UTC
Read the original article Hit count: 395

Filed under:

astronomy

|

colors

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JavaScript

Whilst looking for a "B-V color index to temperature conversion formula"

I found this javascript:

   var C1 = 3.979145;
   var C2 = -0.654499;
   var C3 = 1.74069;
   var C4 = -4.608815;
   var C5 = 6.7926;
   var C6 = -5.39691;
   var C7 = 2.19297;
   var C8 = -.359496;
   bmv = parseFloat(BV);
   with (Math) {
           logt=
              C1
             +C2*bmv
             +C3*pow(bmv,2)
             +C4*pow(bmv,3)
             +C5*pow(bmv,4)
             +C6*pow(bmv,5)
             +C7*pow(bmv,6)
             +C8*pow(bmv,7);

          t=pow(10,logt);
   }

Which is supposed to convert B-V color index to temperature. Does anyone understand how this is working and if the output value is an approximation for temperature in celcius or kelvin?

Is it something to do with products of logarithms?

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