Severe case of heat shimmer
Most never see it with their naked eyes and only through a long lens can you recognize it if you know to look for it. I’m not talking about the Kodiak Brown, no, I’m talking about the real image killer, heat shimmer! Heat shimmer can occur anytime and anyplace from snow to blacktop, winter or summer. It’s even out at sea! Most miss the first signs of its presence when it starts ruining your image sharpness.
very mild case of heat shimmer
A real mild case of heat shimmer can easily be passed off as misfocusing. Many blame everything except heat shimmer for a soft image. In the lower image, the transpiration off the grass is slight yet enough to cause heat shimmer and a not-so-tack-sharp image. In this case, I thought it was there but it was the camera that confirmed it. Heat shimmer will cause the camera’s AF to search and not lock on. Most blame the camera but it’s not its fault. In the photo above, you could see the heat shimmer clearly in the viewfinder and the camera refused to focus. If you don’t look for it, you won’t see it. Have sharpness or AF issues, heat shimmer, it’s a killer!