Weird Bokeh for 35mm summilux pre-a

[yiccciy]

Advertisement (gone after registration)

I just had a Leica 35mm summilux pre-a lens and notice a weird thing in the bokeh. As you can see, the bokeh circled are not smooth, instead there are nets connected by light spot inside. Is this supposed to be a lens issue? 
 

I shot on M6 with Fuji xtra400, F1.4 and scanned with epson V750 
 

Any help is greatly appreciated. Thanks!!

 

(Also I don’t know what’s that yellowish thing behind the green plant..)

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Edited August 6, 2022 by yiccciy

[frame-it]

shooting through a window?

check the negative with a magnified loupe, & check the scanner settings

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

 

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[a.noctilux]

Scanned photos can explain many weird things.

 

[Capuccino-Muffin]

Okay so you bought into the hype without really knowing that Leica is 90% hype... 

Your example is totally normal.

[tommonego@gmail.com]

Shooting through glass isn't making any comment on the lens. Looks to me like some sort of light in the background. The one on the right is a wierd reeflection on the glass. This ain't the lenses fault.

[Capuccino-Muffin]

It’s the moskito grid

[adan]

Advertisement (gone after registration)

6 hours ago, frame-it said:

shooting through a window?

Especially one with a window screen (an evenly-spaced grid of wires)?

All kinds of things can be "imaged" in bokeh/blurs, especially if they are a repeating pattern that can moiré with itself in constructive interference patterns.

Or if the lens has overcorrected spherical aberration to make the sharp areas sharper/clearer (which the all double-gauss pre-ASPH 35s have to one extent or another.) That produces "bright-ring bokeh," and the bright rings can overlap like the Olympic logo and produce artificial patterns.

Monochromatic light like LED traffic lights (all the red is virtually the same wavelength, like a laser) can emphasize the interference patterns.

Consider the "floaters" that our eyes themselves image from time to time (body detritus floating around in the jelly (vitreous humor) between the eye's lens and the retina).

Consider "onion-ring" bokeh from some ASPH lenses - which are simply imaging microscopic "stair-steps" molded into the ASPH surface by the carved-metal mold. An image literally produced at the place where the light rays are "least focused" - in the middle of the lens itself somewhere.

https://www.imaging-resource.com/news/2014/05/02/the-end-of-onion-ring-bokeh-panasonic-beats-the-curse-of-aspheric-lenses

Here's a wide-open shot with the seven-element "King of bokeh" 35 Summicron v.4 - very similar in construction to the 35 Summilux pre-ASPH. See all the bright-ring-bokeh "doughnuts" and how they can overlap to produce doubled images (pith helmet brim, some of the background twigs and branches) and other patterns?

Now imagine a screen or wire fence between the foreground and the background, and therefore also blurred. And how those blurs would interact with the other blurs to produce even more artifact patterns.

It all just boils down to the physics of bending light rays/waves/photons through and around things.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Edited August 6, 2022 by adan

[250swb]

There is to much to go at here. Generally speaking your lens is the least likely cause of any problems with that highlight 'problem'. And beyond that it is equipment or user error. For example if in the background there was a street sign that gave off a digital light display you may see bright spot in the highlights because of the LED light source. On the other hand if it has been very poorly scanned you may also see individual LED's showing up in highlights because of the scanner, but not something I've ever seen with an Epson V750. Generally from a photo where everything is out of focus it is impossible to say if any other faults are chromatic aberration or something else in the background. Maybe try the lens where it is best, f/4 or f5.6 and not at the 'emergency' end of the scale at f/1.4 because the pre-asp Summilux wide open has many optical problems.

Edited August 6, 2022 by 250swb

[ianman]

On 8/6/2022 at 10:33 PM, Capuccino-Muffin said:

It’s the moskito grid

I would have said a thin net curtain but yes, something like that was my first thought too as you can see the thing hanging in other places too.