Spec on ND Filter

So, I appear to have some dirt on one of my ND filters, I am not sure which one... Is there a way to clean it? How did it get there in the first place?

Sheila and Daniel Evans on Vimeo (http://www.vimeo.com/4816673)

You can see it on the shot where I am tilting down from the top of the church.

It is nowhere else on the video and that was the only place I had my ND's on.

It is almost midnight here so I can't go test it out readily...

Thanks for you help!

Well, I had the brilliant idea to go try it out in my bathroom with tons of lights on, and I saw nothing in the VF or LCD. I guess it may have been something on the lens, Though I do not remember cleaning it the whole time cause it looked great...Maybe a small bug?

Sorry to have bothered you!

Feel free to take this post down.

I love it when things like that happen. If you had something on your ND then it would have been a trip back to Canon and your wallet would have been lighter!

Had exactly the same problem as you do, didn't see anything on the lens but the dust spots were clearly there. I had about 3-4 which only could be seen against a clear blue sky. This problem showed on 2 different weddings I did and then the camera was send to Canon.
They replied nothing could be found and when I got the camera back, the spots were gone! Now I wasn"t imagining this, I even included a dvd with some footage showing the problem.

I guess it's just one of those typical things you can get with a Canon.

Scott did you use a crane or gildecam for any of those shots or were you just using a tripod?