Used Leica Apo-Summicron-M 90 - Bokeh balls not round wide open. Is this normal?

[Xelamoon]

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I just received a new to me lens from MPB, and wanted to ask if that is normal or could be caused by maybe misaligned diaphragm? Maybe the lens opens too far?

Attached is a quick example shot of LEDs taken with my SL2-S (if that matters). Only downsizes a bit so that it passes the size limit. 

Third image is from my Tele Elmarit M to rule out the LEDs as a culprit.

Input of other lens owners is welcome.

 

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[jankap]

One can observe:

Picture 1 and 3: Not all bokeh-balls are round.

Picture 2: The balls have an onion structure.

Picture 1 and 2: The balls don´t have a round edge.

The Leica APO-Summicron-M 90 has an element with one aspherical surface.

The Tele-Elmarit is of a classical design.

 

[Xelamoon]

Thanks for your observation, but they aren't all that helpful and only stating the obvious.

My question was not regarding the ORB, and the change of shape due to optical vignetting. 

It was specifically about the jagged balls of picture two.

[jankap]

The onion structure (picture 2) is clear?

The jagged edge can only be the diaphragm. The number of the edges gives the number of blades.

Wide open could be the problem and also the form of the blades. Have you compared the blades of both lenses? Wide open and at f/4?

[farnz]

I had a 90/2 APO-Summicron-M asph for about 10 years and wide open the bokeh balls were perfectly spherical.

It looks like the diaphragm on your lens is not opening fully and is obscuring the round barrel, which is what makes the bokeh balls spherical when the lens is wide open.  It might just be a piece of gunk that's got in behind the diaphragm and is stopping it from fully opening.

If it was me I'd be inclined to send the lens back to MPB if they didn't declare the problem.

Pete.