Square/Rectangular Filters

[RacingHistorian]

I was watching Wind Tunnel last night on the Speed Channel, and they were showing some video from Formula 1 at Indy and there was a photographer, hand holding a square piece of glass/filter over the end of his lens as he was shooting images.   I know of these filters, and I came across an Intro at B&H I think when I was first getting into photography but I don't think I've ever seen anyone use a hand held filter in practice before. 

I was just curious if anyone here has used one, and for what purpose?

[Yammer77]

are you talking about the Cokin Filters?
I think the purpose of them is so you don't have to buy different filters for different size lenses...just the adapters.

[RacingHistorian]

are you talking about the Cokin Filters?
I think the purpose of them is so you don't have to buy different filters for different size lenses...just the adapters.

Sort of.. but it didn't have a mounting system on the end of the lens.  He was actually hand holding the filter right up to the end of the lens (no hood).   

[film2shoot]

I went on a photography outing with a local photographer and he used a polarizing filter, hand held up against his lens. Of course the filter cost more than my flash cost me...

[PanoArtist]

I' ve used Cokin or other square glass filters before - even with digital. They normally come in two sizes. While I have hand held them (to lazy to mount Cokin holder) I usually did use adapter since you can use multiple filters. The primary square filter I've used is a graduated netural density. They are normally rated numerically - for the f stop it applies. I have also used them for extending exposure for water effects when there was to much light for low shutter speed. These are solid netural density styles. 

The only disadvantage I've found is the gelatin filters are very easy to scratch!

Richard - PanoArtist