A little tip for UK based people and that's the used filters from ProAv.co.uk. I picked up a Formatt Polarizer, Formatt ND 0.6 and a Tiffend 1/2 Pro-Mist for £30 each!

Samy's camera is a pro still and video camera store here in Los Angeles. Order from them without fear. They are the LA version of nyc's B&H.

Speaking of clearouts, classic black soft filters are being sold pretty cheap right now directly from schneider. I believe these are the type often favoured by Spielberg -- think war of the worlds was shot with them. Won't work with 2/3 inch chips but seem fine with m43s and larger.

I also bought the Fotga filters and can confirm what n3f0 said. They have a red tint and heavily decrease the detail in the image. Here are some samples:

↑ No ND

↑ Fotga ND2

↑ Fotga ND4

↑ Fotga ND8

I don't have an IR filter but I'm currently in contact with Fotocola and they advise me to simply adjust the white balance and redo the test. I will do that tomorrow or as soon as I have time.

Has anyone seen a 4x4 filter tray that has a hole cut in it with 77mm threads? Basically a metal square that you could attach a threaded filter to for use in a mattebox. I've been looking around but can't seem to find anything.

@Vitaliy_Kiselev

Thanks, hopefully it'll be available soon. Seems like a simple enough concept. I figured it would exist already.

Here's my advice on filters: don't be cheap. There are many ways to cut costs when building up your video gear. Filters are not one of them. Across the board, cheap filters look cheap. I have never seen a cheap ND filter that looked any good. In middle price ranges (e.g. $150-$250 for 4x4 filters) there are some good deals, but anything under $100 is probably going to be crap.