Ugly Bokeh - Sigma whats wrong with you!!

[Skyelark]

I have a Sigma 70mm F2.8 Macro lens - incredibly sharp and generally awesome lens all round.
I use it on FF 5D , sometimes it makes some really ugly bokeh - clearly defined octogons in the blur, see octogon in upper right corner below - not correct!!


Shot at 70mm f4 1/50s on 5D

Am I doing something faulty , or is the lens just junk in that regards?
Would the bokeh kings - the 50mm L f1.2 or 85mm L f1.2 resolve the bokeh in this situation & at the same aperture differently to the sigma - ie in a more rounded or aesthetically pleasing fashion?
Are there any particular canon mount lens that resolve really nice bokeh

[mrb13676]

I have the same lens. Spectacular macro lens, but yes, the bokeh is ugly, even when wide open.

I guess it isn't a lens for those shots that require creamy bokeh. The 50/1.8 is not much better FWIW.

[SteveG]

I've got the sigma 50mm 2.8 macro and I think it's OOF areas are great. I'm playing with an old Pentax 50mm F1.4 (adapted for EOS, of course) that's just awesome one stop down from wide open.

Lenses I'd love to try are the sigma 30mm prime and the Tokina 35mm macro.

I've tried the canon 24mm prime too, although only briefly, and really liked its 'look' too.
Have fun!

[Skyelark]

I've got the sigma 50mm 2.8 macro and I think it's OOF areas are great. I'm playing with an old Pentax 50mm F1.4 (adapted for EOS, of course) that's just awesome one stop down from wide open.

Lenses I'd love to try are the sigma 30mm prime and the Tokina 35mm macro.

I've tried the canon 24mm prime too, although only briefly, and really liked its 'look' too.
Have fun!

Apparently the early Zeiss lens with an adaptor are pretty amazing on Canon bodies.
Has anyone used any/heard about them or seen any pics from an old Zeiss lens on a Canon Dslr?
I'm considering getting the Modern Zeiss 85mm f1.4 but that's manual anyway so maybe I should just look for the old Zeiss lens's which apparently have superb bokeh and due to the vintage glass may slightly warm up your pics (I have experienced that with early Nikon lens and its awesome)

[Forgiss - Sean Nel]

...look for lenses with curved aperture blades or more aperture blades...

[Skyelark]

...look for lenses with curved aperture blades or more aperture blades...

Yes good point , which lens's are well known for that?

[Forgiss - Sean Nel]

Yes good point , which lens's are well known for that?

Sheesh, no idea... My general rules are

1. If you want circular Bokeh Highlights, open wide so that you apperture blades have no effect, If you want shaped, stop down a bit.
2. If you want distinct Bokeh shapes - use a shorter focal length
3. If you want a smoother Out of Focus, use a longer focal length

[Derek Antonio]

If you want great bokeh try the Nikon 135mm f2 DC or the 85mm f1.4...Smooth as butter

[bomtek]

Go and read this article and it will change your perception of what bokeh is completely!

The perception that the largest aperture lenses give good bokeh is wrong. The number of blades also isn't indicative of good bokeh although 8 blades seem to be more consistently pleasing.
Its all about the lens design and the circumstances you're shooting in. Some lenses will perform fantastically in certain areas and very poorly in others.

This page also makes good reading.

Best bang for buck bokeh Canon lenses IMO are the 50mm 1.4 and the 85mm f1.8

[Forgiss - Sean Nel]

Very nice article there Terry!

I will have to amend my last post as a "WTF are you smoking?!" seeing that they rate a 35mm lens as the best performer