Check out camera hacker extraordinare John Kittelsrud‘s magnetic filter holder. He writes: The lumps of tape on the sides of the Cokin filter holder are super magnets with a healthy dose of gaffers tape. These are holding on to two pan washers that are held on to the camera body with, what else, gaffers. I [...]

f295 member greyhoundman has posted instructions for how to build an ultra-cheap filter holder for large format lenses: Ok, I know someone probably sells an adapter for holding filters on a large LF lens. But, not around here, and I like to see what I’m buying. So again I decided to build what I need. [...]