Square Bokeh?

[DRappazzo]

Great Thread!! I can't believe that I had not thought of doing this before, when it seems so obvious. Thanks for all the great info.

 

[Luis de la Cerda]

Copyright that cause someone is using your idea as we speak. :yesnod:

With a BW LCD as a hard matte in front of the lens you could even make animated bokeh...

girls dancing, letters, etc...

 

[Roberto Lequeux]

With a BW LCD as a hard matte in front of the lens you could even make animated bokeh...

girls dancing, letters, etc...

HAHAHA... like projectors? You could! I like where this is going... I guess the trick would be in making sure you focused back and forth to make it evident that it is an actual optical effect and find good motivations for the focus racks, work it into a concept for the video. Neat idea Cholo.

 

[Joe G.]

I'm thinking you could fake anamorphic looking bokeh.

 

[Gavin Greenwalt]

Trying it this very second.

 

[Gavin Greenwalt]

Ok here are my findings.

This would be hard to do with anamorphic. In order for the aperture to 'crop' the bokeh it has to be pretty much in frame.

This works alright with a square frame. By the time I got my aperture large enough to not cause significant vignetting it was already taking up half the frame (the nature of a vertical aperture on a horizontal frame). So you would have to crop down like 50%+ of your resolution.

Also the shaping effect is largely only in the dead center of the frame unless again you're willing to accept pretty dramatic vignetting.

Square leant itself well to the experiment. I imagine this would work pretty well at night as well since the vignetting wouldn't be terribly obvious.

And maybe someone could get satisfactory results with a better setup and more time. I just used the back cover of my employee benefits book and a box cutter. Still it wasn't what I would call exciting. So unexciting I didn't even bother taking a picture of its round/vignettiness.

 

[Roberto Lequeux]

What about having a 2nd AC or the first holding sheets of paper with holes of various shapes cut on the same sheet and moving rapidly from one to the other... possibly a long jagged edged hole also to slowly pull through... though I guess you would get into exposure issues... but maybe with some experimentation you could achieve some sultry/gnarly optical mayhem! Surely not a simple shot but it might be interesting enough to work into the schedule. I got a spot where I planned to remove the lens, but I am thinking of adding this to it now...

...maybe to simplify things it could be an oval like anamorphic, but make it so you can spin it... or an oval composed of two cutouts, one for each half of the oval allowing you to increase and decrease it's size...

...just thinking aloud here... can someone tell me if they see exposure being an issue with increasing and decreasing the overall size of the opening?

 

[Gavin Greenwalt]

You aren't actually decreasing the size of the opening all that much. So the light loss is probably less than a stop.

It only really works well on the longer glass from my experiment. And that square shot was like .5" tall. And it has to be perfectly centered on the lens so quickly switching would probably be too difficult.

If you want crazy animated bokeh it would be best to just shoot on a green screen ala Speed Racer.

 

[Roberto Lequeux]

I am looking for an optical effect though, and a cheap one...

 

[Nick Everett]

Does anyone have any idea what caused this? Its shot on s16mm

Spooks Series 9 Ep 3

Shot with square boken

The reverse with normal boken

 

[Emyr R. E. Pugh]

I don't know why this had never crossed my mind before and just had to give it a go; works surprisingly well.

Here's the bokeh version of the Mongolian word for 'light' shot on a Zeiss CP 85mm 1.5.