Originally posted by RICHARD L. California (Death Valley sand dunes, Yosemite and San Juan Capistrano Mission), Arizona (Mount Lemmon near Tucson), Utah (Arches - Balanced Rock), Texas (Welcoming Center on Interstate-40).
AF wasn't really required for those, but sunny daytime was about the only time the K5 AF worked. I got very nice outdoor shots with mine as well.
I was shooting a lot in the studio when the K5 was current, and under those conditions the AF was worse than useless as the colour of the halogen modeling lights threw the AF out. It was extremely colour sensitive, and would vary from extreme front focus to extreme back focus depending on the colour in front of it.
Perhaps not so much of a problem in daylight when everything is near infinity and the lens is stopped down, but at portrait apertures and closer focus distances, it was a disaster. It was the same under street lights or any other artificial source. The very good high ISO abilities of the sensor was somewhat nullified by the fact the AF wasn't consistent or accurate under lighting conditions that would tend to be used at high ISOs.
I did some reading in the K5 forum, going right back to when it was released. I had forgotten about the front and rear control wheel issues, as well as problems with the mode dial.
A lemon in the automobile industry is a car with an unacceptable number of bad samples.
The K5 was such a camera. I'm glad yours worked for you, but for a large number of users, it was a bad camera. They did get the sensor stains fixed as it was a production problem on a run of them at Sony, but I don't think they ever sorted out the issues with the AF, mode dials or buttons falling off.