Damn! I remember when I was buying Cokins they were regarded as the "bees knees" and relatively expensive. I must admit that was close to 30 years ago
. I've just (like in the last hour) picked up a 40D off Ebay so I might just get a chance to start using them again.
Dithering/feathering with filters seems to be akin to working the exposures under an enlarger. Anyways, I'm watching this thread with interest as I'm learning something new