Here is another photo of a domino. I used f/2.8 because I did not need any depth of field. I was shooting this on the corner of a table with my tripod legs around the corner. I was on over top of the domino. I thought I was anyway. It turns out I was not quite directly over top. I was not careful enough with my set up. You can see the bottom right and top left are out focus. If I had used a smaller aperture I would have been ok as well. I will be more detailed in my set up next time.