Need help! Bokeh question

[Timber Wolf]

Crop 100% of a 24-70mm Sigma f/2.8 @ 70mm f/2.8. Set out of focus at highlights pointed at infinity

That is one heck of an ugly bokeh! Is this normal? Any way i can correct it?

Thanks
QX

 

[jbma]

I don't think this is the correct way to get a good bokeh. What you are getting here is an OOF image. Try to take something close at f2.8 in the daytime and then see if the background is what you expect it to be.

 

[Timber Wolf]

Well, technically bokeh is background blur, so what i'm doing is simulating it. My 75-300 f/4.5-5.6 can produce a nice uniform circle without the dot in the centre. I'm wondering if it's a lens fault?

Thanks for comments!
QX

Gurus please comment :bsmilie:

 

[grado]

Some of the Sigma lenses, I find, are weak in bokeh. I think it is the lens bokeh.