What’s wrong with this picture?

Photographing Siberian tigers in China during the winter when they are in their full winter coats is thrilling. It’s easy to be so enthralled with the big cats that you forget about the technical details of shooting. That’s what happened here. The tiger on the right was about 12 to 18 inches closer to the camera than the cat on the left, and the 500mm Canon lens I was using didn’t offer enough depth of field, even at f/8, that would encompass both animals. I focused on the tiger at the left and, therefore, the tiger on the right isn’t tack sharp. Enlarge this picture on your computer, iPad, or smart phone and you can see it clearly. In my opinion, the image is seriously degraded because of this flaw.

When there are two subjects in the composition, they should both be sharp,

virtually without exception. Due to the limitations of the laws of physics, this isn’t always possible.

I recognized the problem immediately, so after the first shot I quickly re-focused on the tiger on the right and took another picture. You can see in the time between shots, the cat turned its head slightly away from me.

In Photoshop, I replaced the out of focus tiger with the sharp one. To blend the two heads, I created a layer mask and varied the opacity as I blended the two images. This was tricky around the whiskers, but with patience and attention to detail, I made it work. §