They're all shot with a Nikon D80 that's been fully converted to IR. I don't use any other filters or means of taking the shots. I tend to throw a polarizer on the lens and that's about it. The workflow is usually channel mixing with the red/blue inverted and then just basic pic cleanup. Thanks for the comments
I don't know what you mean by making lenses with a mark. I sent my camera to lifepixels (I think it's www.lifepixel.com). There's a bunch of info on their site. You can use a Hoya R72 filter, but it's kind of a pain. I knew I really wanted to do a lot of IR shots, so I had the conversion done.