Jump to content

Explain OOF, Bokeh


pico

Recommended Posts

Advertisement (gone after registration)

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 by pico
Link to post
Share on other sites

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.

 

Link to post
Share on other sites

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 by pico
Link to post
Share on other sites

 

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.

Link to post
Share on other sites

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.

  • Like 1
Link to post
Share on other sites

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.

  • Like 1
Link to post
Share on other sites

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 by pgk
  • Like 2
Link to post
Share on other sites

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

  • Like 4
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...