If you were on a desert island with your XL H1 and only one filter...

[Jonas Nystrom]

...which filter would you choose?

So after my Matteboxe thread I bought a clamp-on Chrosziel 4x4 Mattebox. Great Buy, I will recomend for everyone who into any kind of video. I've also bought a graded ND 0.6 and a 1/2 Black Frost (both Schneider). Lovely and magic. Graded ND will take you to heaven. And with the black frost, the video turned into the proximity of film (OK, nearly ;-).

OK, I know, you can grade in post or in the NLE. But really, in HD or HDV, with 25p filters. You got to have a lot of patience with rendering times...

So I'm in love with Matteboxes and filters. I've got the Mattebox, and two filters. I can tell you, I need a lot more filters. Below is Steven Dempseys recomendation. Give me more, give your favorites, give me your survival kit!

ND FILTERS:
Either .3 or .6 or .9 (1,2,3 stops respectively). If you are interested in achieving maximum shallow depth of field within the capabilities of the camera, these are a good choice. They will force you to open the iris more, allowing you to creatively focus on your subject when shooting medium to closeup shots. They will also help you keep the aperture at a sweet spot in terms of sharpness if you are shooting a bright light source. Closing the iris down tends to soften the picture and NDs help to alleviate that problem.

GRADUATED ND FILTERS:
If you are shooting vistas, this is a great addition to your tool kit. These filters allow you to bring the contrast ratio between land and sky more into the range of what the camera can see. It will also allow you got get some pretty dramatic skies with plenty of cloud detail.

UV FILTER:
Buy one now and keep it on your lens if you don't already have one. Essentially, this is just a clear glass filter that protects your lens from the harmful UV rays from the sun but it also acts as a protection against scratches, etc. on your actual lens.

PROMIST/CLASSIC SOFT FILTERS:
These filters have the same effect as soft focus. Remember the women that Captain Kirk falls in love with on the original Star Trek? The DP would simulate that misty-eyed love struck moment by giving both Kirk and his love interest (particularly the latter) an exaggerated soft focus. These filters can also be used to hide skin blemishes and take the overall video harsh sharpness out of the picture. Summary: they soften the picture in a pretty way.

COLOR/SPECIAL EFFECTS FILTERS:
I personally stay away from these because I'm paranoid about getting a great shot and realizing that the effect ruins it because the effect is too much. I usually can achieve the same overall effect in post. There are many good uses for these kinds of filters but I would keep their use to a minimum. The novelty wears off very quickly for the viewer.

The exception to this is if you are shooting black and white. Many of these color filters (yellow, in particular) help to enhance contrast in your shots and make the black and white rendering much richer. There's plenty of info on the Web about creative black and white photography.

CIRCULAR POLARIZER:
Generally used to enhance the blue of a sky and make the clouds pop but it is also used to minimize reflections on windows and in water. In fact, a good quality polarizer can be very effective at removing unwanted reflections say if you are shooting through a car window, etc.

[Craig Chartier]

I would take a +3 diopter so I could use it to start a fire.

[Jonas Nystrom]

Ha ha ha :-D good one!

[Craig Chartier]

truthfully, once you have a mattebox, filters become addictive.

[Nick Hiltgen]

polarizer. I've personally become a huge advocate of them. Plus if you're on an island you're going to want somethign to take the glare off of all tha water...