I have a question regarding the quality of my Sigma 70-200mm f2.8 (non-Sport) lens. I bought this lens back in 2011, and even though people say again and again a 70-200mm is a must-have, this is my least used lens. I photograph mainly sports and wildlife, and I mostly avoid this lens. At wide apertures, I know that the DOF is very narrow; however just about everything in any image I shoot with this lens at any aperture wider than f/8 is blurry and/or out of focus.
I took a couple of test shots at f/2.8 and here they are (unedited). Both images were shot at ISO 250 at f/2.8 and a shutter speed of 1/4000.
In the image of the solo athlete, the focus was on the athlete's jersey; however only the "Rocky - 21" graphics and her v-collar are sharp, not even her face is. If you look by the soccer ball and really on the entire left half of the image, there seems to be a radial blur around the athlete. I am well aware of bokeh at wide apertures for objects that are not in-focus, but this looks like motion blur moving circularly throughout the left half of the image.
The second image of a larger group is similar. I will say, though, that this shot was unplanned, in that there is no true subject, as I just fired the shutter without thinking. There is an athlete, that just happened to be in focus here – the girl in the way back to the right of the girl with the pink headband.
I have seen plenty of f/2.8 sports shots where, yes the background is out of focus, but the entire athlete is sharp as a knife. Has anyone else experienced this with their lenses? Is it an elements issue. I agree, this is an older lens, but I had this issue even when I bought it. I have another Sigma telephoto lens that performs similarly at wider apertures. So all of my sports photos (at least daytime) are shot at f/9 or tighter because that will produce sharp images. I have been critiqued with the fact that a narrow aperture will create a busy photo because you can see more of the background, which is true, but otherwise none of my images will be sharp. It might be hard to tell because of the compression requirements for this forum.
Thank you all very much for taking the time to read this. I hope I did a good job at explaining this because I stumped the employee at my local photography store. If this is something that happens naturally, just tell me bluntly haha. I have never worked with Canon or Nikon glass, so I figured it was a third-party thing, but I am totally stumped.
[EDIT]: As comparison, I found this blog entry from Rick May. If you scroll down a bit on the page, he has a sample image with his 70-200mm 2.8. link: https://alphauniverse.com/stories/what-s-in-my-bag--how-a-sports-pro-built-an-ultimate-sony-lens-kit-for-fast-action/
For these images of mine (and others I have taken under these conditions- not provided), it looks like, to me anyway, someone has taken their hand and smeared it across and smudged the image.