Jupiter 8 bokeh

[vox20]

Hello.

Attached are crops from 1500*1000 scan of picture taken with Jupiter-8 at Zorki fully open - from the middle of the longer side of frame and from the corner.
The questions are -
1. on what f stop the bokeh shape in corners become more or less circular (f/4 I guess ? )
2. on what f stop ( if any... ) the bright line on the borders of spots become not so pronounced?

 

[payasam]

Simplest way to find out would be to take pictures of the same scene at different apertures.

 

[Spyderman]

Find out here (click).

BTW: the pronounced "donut" goes away as soon as you stop it down a little (like f/2.5 or so...)

 

[vox20]

That's comprehensive. Thanks.

 

[mike goldberg]

Ondrej, the info in your Blog on the J8 bokeh is great!
Mike

 

[Spyderman]

Thanks Mike. It was a RFF thread first, only then I copied it into my blog...

 

[Paul T.]

Terrific. I was pondering what camera to take with me when I pack for holiday tomorrow night, and you've just reminded me how much I like my J9, so that will definitely be going in the bag