title: Convert a color from colorWithRGBA to colorWithWhite
body: <p>I've been using a hex calculator to convert hex values to RGB values ( #666 = 102/102/102 and so on).</p>
  
  <p>It seems I can't use this with UIColor though, <code>[UIColor colorWithRed:102 green:102 blue:102 alpha: 1.0]</code> just seems to return white (tried 60 too). If I use [UIColor colorWithWhite: 0.6 alpha:1.0] I get a dark color- so how can I convert a value like 102/102/102 into a colorWithWhite value?</p>
  
  <p>A way I've tried is to take that value and divide by 255, so 102/255 = 0.4 so I set my <code>colorWithWhite</code> value to 0.4. Is that accurate?</p>