title: Setting image DPI in relation to height/width C#
body: <p>I'm writing an application to send some images to a third party, and the images must be 200x200 DPI.  The image is a Bitmap and is sized at 500 width and 250 height.  </p>
  
  <p>The first time I tested the images with the third party, my resolution was incorrect.  I merely used <code>image.SetResolution(200,200)</code> to correctly set it to 200x200.  This, however, only changed the resolution tag for the image and did not properly, according to my third party technical contact, adjust the image height and width.  </p>
  
  <p>Is there a ratio that I can use so that for each X units I increment the resolution, I merely increment the corresponding height or width Y units?  I thought that I could just increment resolution without having to increment height or width.  </p>
  
  <p>Thank you,
  Aaron.</p>