[robski]

Another factor with wide angle lens is that you need very low profile filters to reduce the amount vignetting the filter rim can introduce. This goes against the way that graduated filters in the Cokin System work. The large Cokin Pro systems maybe large enough to avoid this problem. I have dabbled with the Cokin graduated filter in the past. The countryside on my local patch does not lend itself to great landscape shots.

I found care is needed when setting the exposure. You can find yourself reading though the darkened part of the filter which then negates the effect of using the filter in the first place.