title: Retina display and [UIImage initWithData]
body: <p>I need to initialise images from raw data downloaded from a server which delivers the correct size of image based on the type of iPhone client.</p>
  
  <p>I know that I should be setting the scale value to be 2.0 on the 640x960 display, however this is a readonly property and cannot be set during the init when using initWithData.</p>
  
  <p>Any ideas?</p>