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You are here: Home / The Last Word / Baby steps toward off-axis bokeh simulation

Baby steps toward off-axis bokeh simulation

May 7, 2017 JimK 1 Comment

This is the eighth in a series of posts about building a bokeh simulator. This series starts here.

I’m still struggling with how to efficiently program the off-axis bokeh simulation, but I did write some code to do a simulation with a static offset, if that out of focus (OOF) point spread function (PSF) is run against the entire image.

Here’s the result of a run a 50-pixel disk PSF (on a 2500×2250 image) with no occlusion, scaled down to web dimensions:

Now let’s imagine a lens that occludes quite readily, with a diameter of the occlusion the same as that of the on-axis OOF PSF.

This sim gives us this:

You can see that the blurring is diminished, but there’s an odd quality to it. The occlusion that I picked would make the image darker in a real camera, and it would have in the sim, except that i compensated for it.

Same idea in the other direction:

 

And in the corner:

 

 

 

The Last Word

← Off-axis OOF PSFs of the Sony 135/2.8 STF Leica 280/4 Apo-Telyt-R on Fujifilm GFX 50S →

Comments

  1. CarVac says

    May 7, 2017 at 6:38 pm

    The simplest way (if a bit cheat-y) would be to do a bilinear blend between the nearest four PSFs.

    Reply

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