Chief_10Beers wrote in post #17612698
After reading thru this entire thread I went out and tested my copy of the 17-55. The Lens is Mated to my 60D. I took eight shots each at 17, 20, 24, 35, 55mm at f/2.8, ISO 200 and 800th-1000th sec. One shot, center AF, Hand held with Stabilizer On. It was Cloudy and the Test Target was a house a little over a 1/4 mile away. I had no OOF shots, all were sharp.
I don't doubt you one bit Archibald, I'm pretty sure my copy will not work on your 7DII. The only thing I can think of is the New and Old Tech are choking on each other. It's almost like there is a com issue but not enough to trigger a fault? ...............
Okay, I have to ask you if you checked the distance scale when you did your tests. You didn't mention, so I assume you didn't.
The distance scale provides a better way to check for AF errors. It avoids pixel-peeping, which everyone does differently, probably leading to different conclusions depending on the person. Checking the distance scale is less subjective.
You don't have to have your gear on a tripod for this. You can just look at the distance scale right after taking a shot. If you are shooting at something far away, the scale should be on infinity. If it is not, then the AF malfunctioned.
Now let's do a thought experiment. What would happen if you and I exchanged gear? You got my 7D2 and 17-55mm lens, and I got your 60D and your 17-55mm lens. Then we went out and did some shooting and ran some focus tests. What would we find?
I am almost for sure that you would find no problem with my gear, and that I would immediately see intermittent AF errors with your gear.
Obviously we can't do such a swap. But I did something similar to this about a month ago... I took my body and lens in to a reputable camera store here in town. Their help is knowledgeable, many are pro photographers. I told the guy there about the problem I was seeing with the 17-55mm lens. The two of us went outside and took a bunch of shots, and scrutinized the pics on the LCD. The AF errors were obvious! To me. The store guy shrugged them off, he scoffed even. He said that it was normal, all lenses are like that. Then he went about his business helping other customers.
Evidently most users of this lens are happy with the results. And that is in harmony with the opinion of the sales guy.
Some guys are not happy, though. Those guys have tried multiple copies of the lens and find the same unsatisfactory AF with all.
But the 17-55mm does have an AF problem, and other lenses like the 15-85mm, 18-55mm II, and 18-55mm STM don't. There is a demonstrable difference.
So that's my conclusion. It's all in the eye of the beholder.
If you like the results, carry on!