Explain OOF, Bokeh

[pico]

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This topic is not a trap. Seriously. I am persuaded now to inquire since seeing examples from Karbe's amazing 75mm Noctilux which seems to have none of what I considerable objectionable OOF characteristics,

 

I cannot find the source. The one I recall had examples of bokeh | OOF and it gave in optical terms profound explanations for different OOF.

 

First, let us consider only wide-full-open apertures. No discussion regarding the obvious highlight shapes due to diaphragm shapes, circular or otherwise.

 

Some images' OOF have nervous double images of, for example, tree branches and their highlights occurring side-by-side as if reflected. That is the one that puzzles me the most. I hate it. Others that cope very poorly with highlights by creating subtle edges around them are interesting, but not to me.

 

On the other hand those with circular swirl I understand.

 

Do any of our constituency have a source examples of the above or others I have missed?

 

Thank you in advance.

Edited April 18, 2018 by pico

[CharlesL]

Do you want to see sample photos? Search on a lens name and "bokeh." For example, within Flickr, you can get 1,200 examples for Summarit lenses with

https://www.flickr.com/search/?text=summarit%20bokeh

You could also put a camera model number in the search in an effort to exclude examples of lenses mounted on Sony, Fuji, and other cameras.

 

[frame-it]

1.4++ million pics here >>

 

https://www.flickr.com/groups/bokeh_/pool/

 

 

filtered the Leica tagged shots, over 20,000 >>>

 

https://www.flickr.com/search/?group_id=38343303%40N00&view_all=1&text=leica

Edited April 19, 2018 by frame-it

[pico]

Okay for the search suggestions but I have seen and made bokeh. Believe me. And I know how to search, too.

 

I was looking for explanations of certain distinct patterns.

Edited April 19, 2018 by pico

[jdlaing]

 

I was looking for explanations of certain distinct patterns.

Firstly, bokeh is not the out of focus area. Bokeh is the quality of that area.

The lens elements, how they react with one another, and the aperture blades play a part in the smoothness of the OOF.

Light sources, as well as dramatic light and dark spots and areas, have an effect.

Lastly, distance between the focused area and the OOF elements will have an effect on the rendering.

[pico]

Firstly, bokeh is not the out of focus area. Bokeh is the quality of that area.

The lens elements, how they react with one another, and the aperture blades play a part in the smoothness of the OOF.

Light sources, as well as dramatic light and dark spots and areas, have an effect.

Lastly, distance between the focused area and the OOF elements will have an effect on the rendering.

 

Thanks for nothing, Captain Obvious.

[Exodies]

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One man’s obvious is another man’s oversight.

 

One manslaughter is another man’s laughter but that’s another story.

[frame-it]

feel free to search on siggraph for documents regarding the variable patterns and what creates them in the bokeh blur areas...plenty of research as people have created tools to recreate these aberrations.

 

https://www.siggraph.org/

 

 

 

 

 

Okay for the search suggestions but I have seen and made bokeh. Believe me. And I know how to search, too.

 

I was looking for explanations of certain distinct patterns.

[pgk]

Zeiss have published an explanation of lens design and the factors influencing oof/bokeh. I have a downloaded copy somewhere and will try to locate it because there is too much to search through on Zeiss's website to refind it easily. I'll have a look later but you could try searching through the Zeiss website - they have published a lot!

 

Perhaps I should add that bokeh is not rocket science but it is optical design science not just something which happens magically.

Edited April 19, 2018 by pgk

[Nordvik]

Zeiss have published an explanation of lens design and the factors influencing oof/bokeh. I have a downloaded copy somewhere and will try to locate it because there is too much to search through on Zeiss's website to refind it easily. I'll have a look later but you could try searching through the Zeiss website - they have published a lot!

 

Perhaps I should add that bokeh is not rocket science but it is optical design science not just something which happens magically.

https://diglloyd.com/articles/ZeissPDF/ZeissWhitePapers/Zeiss-DepthOfField-Bokeh.pdf