TIFF | GIF | BMP | PNG | |
---|---|---|---|---|
Main Usage | For high quality camera and scanned images | For basic animations | For displaying different shades/depths of colors | For displaying opaque and transparent images. Appropriate for websites |
Quality | High. | Good for displaying basic images with animation | Good for displaying grayscale image | Low as compared to TIFF and JPEG |
'Unfortunately, the 'Dots per inch' option is no longer available in Office for Mac. If this is a feature you'd like to see in future versions of Office for Mac, be sure to send your feedback by clicking...' blah.
See here: http://www.officeformac.com/ms/.59bcff97/0So, it looks like from now on in order to create high resolution images out of your Excel figures it will be necessary to use something other than PowerPoint.