da*300 f4?

The Sigma 150-500mm certainly isn't soft at 500mm.......
This is at 500mm f/8 ....... f/11 is even sharper.
I often use it with a 1.7TC = 850mm and it's still sharp...

Click for the bigger image....

https://www.pentaxuser.com/photo/user-11130/young-blackbird---sigma-150-500mm-29...

This member produces some of the best bird photos I've
ever seen with a Sigma 170-500mm mostly at
500mm wide open. Some at 1600ISO on a K-7 and
cropped.

Just goes to show that a lot of technique involved.
The camera and lens won't take the shot themselves and
lenses are for using not fondling If you can't
drink a cup of tea without spilling it down yourself
your never going to hold a 500mm lens steady

https://www.pentaxuser.com/user/pentaxanne-10778


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