I'm looking into expanding my current filter set beyond the standard UV filter that protects my lens. Since I'm also planning on getting more lenses in the near future, I've been eyeing the Cokin filter system. I'm already well aware of the obvious pro: I can have one set of filters for all my lenses instead of buying new filters for different lens diameters.
But what about other pros and cons? How are the optical quality of Cokin filters? Do I get the same range of filters with Cokin as with conventional screw-on filters? Is the convenience and price worth it?
I have used both systems, the screw-type and the Cokin holder-type and have abandoned the second one. In theory the Cokin is more convenient (you can used more than one at a time, graduated filters can be placed at the right height, etc.), however availability of filters is not that good at the corner shop, although price-wise they should remain less expensive than those needing the threaded ring. I guess in the end it is, again, a matter of personal taste. Have a great time JRP (Nikonian at the north-eastern Mexican desert) My profile, My Gallery Previous photographic journey, before Nikonians: A Brief Love Story
I use round glass filters whenever possible. However, if you are working with gradient filters (very useful for bringing a bright sky into balance with a darker foreground), rectangular filters are far better to work with. A round gradient always has it's blend in the center. A rectangular filter gives you the ability to positon the blend where it works best.
Just don't buy Coking neutral gradient filters. They're grey rather than neutral and dull your image. I recommend Hitech filters to fit Cokin holders. They're high quality, but not overpriced. Go with the Cokin P mount size so you don't get stuck with a system that is too small for your lenses. Stick with round glass polarizers and think about using Photoshop instead of spending a fortune on color filters.
I also use both - the Cokin-P system and standard, glass, threaded filters.
Don't worry about filter and lens size. I buy filters in the 77mm size (where affordable) and the 62mm size. I then use stepping rings to fit any lens size for application. I gennerally buy Nikon filters, but have Sigma and Hoya as well.
Of the Cokin-P system, I wanted the larger size to fit the lens range. I use these primarily for gradient filters only. Some are Cokin, but most are offbrand, like Hitech, Hoya or others. ND's in various hues are cool - I have grey, magenta, dark magenta, blue, red, orange and green. They present some pleasing results.
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