Science behind light bleeds?

[Max Field]

Take note of the blue light bleeding in at the top right corner:

This was shot on an Arri Alexa EV with a 50mm Zeiss CP2. 2 Arri 650s about 7.5 feet high pointing down at a cross to backlight the talent.

The big question I have is on the science for intentionally creating more light bleeds like this, I'm in love with the look. I try to trigger it through just fiddling with angles but I have no real consistent way of knowing how to make it happen every time. Is it dependent on the lens? Does sensor size affect it? Intensity of the light?

Please, any knowledge you have on this will benefit me greatly. Thanks as always!

 

[John Brawley]

1 hour ago, Max Field said:

Take note of the blue light bleeding in at the top right corner:The big question I have is on the science for intentionally creating more light bleeds like this, I'm in love with the look. I try to trigger it through just fiddling with angles but I have no real consistent way of knowing how to make it happen every time. Is it dependent on the lens? Does sensor size affect it? Intensity of the light?

Please, any knowledge you have on this will benefit me greatly. Thanks as always!

 

This is known as veiling flare.

Most lenses will do it to some degree, usually when backlit or shooting into the source.

Hotter and larger sources will do it more rather than the point source you used here.

So say lace curtains in shot around a window and glowing hot in terms of exposure will do it.

Modern lenses tend to have better anti reflective coatings and will subdue this more than older lenses will.

Any filter or extra glass in front will also create extra veiling flare in this scenario, even a "clear".

JB