Applying a 'dusty' look to an optical flat

[Matthew Greiner]

Hello everyone,

 

I'm shooting a scene involving a character who's been locked in what would visually equate to an underground prison cell for many years and my intention is to create a very dark and gritty look. So, I've been exploring different ways to do that in camera as well as through lighting and I am wondering if anybody has experience applying a 'dusty' look to a clear optical flat filter? Is there some kind of spray I can buy and apply to it without causing any damage to the filter?

I'd like the scene to appear almost as though we're seeing it through a dirty window pane with a texture similar to the photo below.

 

 

Matt

[David Mullen ASC]

Unless you are going to stop down enough so that the front of the filter starts to come into focus, or use a much larger piece of glass farther from the lens, or use a small sensor camera with a lot of depth of field... you aren't going to see any dust particle effect on the filter because it will be too out of focus. At that point, something like a Smoque filter or a LowCon would be enough to have a bit of haze. I mention a small sensor camera because when you stop down too much, filter patterns like the black specks on a Black Promist do start to come into focus enough to feel like a dirty lens. GlimmerGlass also has a similar effect because of the silver glitter on the filter.

 

If you were using one of those depth of field adaptors that project a lens image onto a groundglass surface, that can also add that texture to the image. Some people have even set-up a large format camera, like an 8x10, and rephotographed the image on the focusing screen.

[Matthew Greiner]

Thanks for the quick response, David. I'd like to keep the dust particles out of focus, but obviously I want them to play on camera, so what I think I will do then is use a larger piece of glass like you said. Because this is only a short section of a much larger narrative, using a smaller censor camera won't be financially possible. I will however have a smoque filter on-hand for some other scenes, so I might as well see how it looks for this one as well. Thanks again. :)

Edited October 6, 2013 by Matthew Greiner

[Phil Rhodes]

I hate to be the guy to say it, but this stuff is very readily done in post.

[Mark Kenfield]

using a smaller censor camera won't be financially possible.

 

Have to say it - I can't even find the words to express how happy this sentence makes me. It's not something I'd ever have imagined hearing just 5 years ago!