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abstrax wrote:During the discussion in viewtopic.php?f=9&t=44522 I realized that the aperture calculation was incorrect, since it calculated the aperture diameter instead of the aperture radius which is what the aperture pin actually specifies. I fixed the script in the opening post.

For fun and out of curiosity I did a little experiment to see how closely the Octane DOF matches a real world photo. So I set up a simple scene with a black pen in front of a white wall and have the wall in focus. I measured the various dimensions and distances and then roughly recreated the scene in Octane via C4D.

This is photo taken with a Canon EOS 550D (sensor size is is 22.3mm x 14.9mm) and a Tamron lens set to a focal length of 50mm and the aperture set to f/2.8 and processed in Lightroom:

IMG_7881_sm.jpg

And this is the approximated scene rendered in Octane:

test_0_8.png

In the image above, I set the "aperture edge" in the camera node to 0.8, but it's hard to get the bokeh into the same ball park, especially since Lightroom also applies some fancy non-linear response and the Tamron is certainly not the lens with the smoothest bokeh on this plant. But yeah, it's pretty close I would say.

This is how it looks like with an aperture edge of 0.5:


This is the scene to render the above image:

In the plugin I use this feature is called "Bokeh sharpness" so I kept overlooking it in the standalone.
Guess now I will hopefully finally remember.

Great idea with the pen example! It is impressive what can be achieved when knowing how to work with the standalone.