Canon EOS utility and tethered shooting preview quality

Canon DSLRs come with a software bundle and one of the applications is EOS Utility. Among other features it allows you to transfer your shots right away to your computer over USB cable and it also displays a quick preview of the photo on the computer screen. This is pretty handy because it is much easier to see results on the big screen. Obviously the USB cable length limits your movements so I guess people will use this for studio shots mostly.

I was playing around with this feature and I noticed that the preview had rather bad quality. After trying out different settings it turned out that shooting in RAW+JPEG mode instead of RAW only resulted better previews. Apparently the quick preview's RAW conversion outputs only low resolution images.

Meanwhile, in the laboratory...

I just realized I have been downgrading my photos because of a low quality UV filter. The bokeh looked horrible and focus seemed to be off so ended up setting up a test setup and shooting plenty of frames with different settings. Soon It was quite clear that cheap Jessops branded filter was the culprit. But I also learned quite a lot about how autofocus works and what might cause it to miss the spot. But more later with example photos.