Strange bokeh with Tamron 17-50mm f/2.8

[wise]

I just purchased the Tamron 17-50mm f/2.8. And I am pleased with the results so far, except for the bokeh which is kind of strange sometimes. You can see concentric circles in the out of focus highlights. I`ve tested the Tamron 28-75mm f/2.8 and didn`t have that problem. So here is my question: Is this kind of bokeh normal for that lens or did I just receive a bad copy?

 

[AUZambo]

That's interesting...can you post a pic? I've got the same lens for my Sony A700. I haven't noticed anything weird about the bokeh, but I haven't really looked that hard either.

It's easily my favorite lens of my small collection.

 

[wise]

Here`s an example:

And a crop of the bokeh:

 

[benhasajeep]

That is lens flare that you are getting. Light is bouncing / reflecting from the direct light. Coatings help this but can't completely prevent it from happening.

 

[lamergod]

That is lens flare that you are getting. Light is bouncing / reflecting from the direct light. Coatings help this but can't completely prevent it from happening.

it's not flare......... it's light,try using manual focus and out of focus at a area with lots of lights like at a traffic or something,the lights would become circle,it's called Hollywood style bokeh,can't be help

 

[benhasajeep]

That is lens flare that you are getting. Light is bouncing / reflecting from the direct light. Coatings help this but can't completely prevent it from happening.

it's not flare......... it's light,try using manual focus and out of focus at a area with lots of lights like at a traffic or something,the lights would become circle,it's called Hollywood style bokeh,can't be help

Actually probably right. It's more reflected light bouncing in the lens. Can tell by the concentric circles in the ghost lights.

 

[wise]

@lamergod: The problem is not that the out of focus lights become a circle. Actually this is what I wanted. But these circles within circles are untypical and look strange to me.

 

[Overread]

It looks like the doughnut shaped bokeh one gets off highlights when using a mirror lens. Out of interest are you using a filter on that lens - if so have you tried removing it to see if that could be contributing to the problem?

 

[wise]

No, I don`t use a filter on that lens.

 

[Big Mike]

I use that lens and I can't say that I've ever seen that before. But I don't have a lot of shots in that type of situation. :scratch:

 

[Derrel]

Some people call that "bright line" bokeh. Others call it "onion" bokeh, due to the obvious,concentric circles it displays,and how it looks kind of like an onion slice, with you know, the rings...