You might need to "wait" for a candid. I got a fairly good one of my cat by the luck of the draw. I had all of the blinds open in the house during a weekend afternoon, so lighting was decent. I also had the camera set to a relatively high ISO of 1000, which left a little grain but not too terrible.
I found that sitting the camera on the floor helped. My cat showed some interest, and I snapped as he was looking at the camera in a "what's this?" sort of way.
The pic is
here if you're interested in taking a look.