Hi, Steven. First, it is a hazard to use Cokin P on lenses with >77mm filter diameter. The reason is simple. If you measure the diameter on inside of the Cokin P holder, it's 75mm. I know it is proclaimed to work with some lenses of larger diameters, but don't count on it. It produce detectable vignetting with lenses like 645A*300/4, 645A45/2.8, FA*400/5.6 and to some extent on FA*24/2 and FA20/2.8.
I know, why put a filter on a 400, but a gradual gray comes in handy sometimes anyway. Its is true as has been said about the cokins that they can change colour over time. My gradual gray (G2) give a slight green cast, and recently I discovered my pola to give a blue-greyish tint. They're both in line for the thrashcan as soon as I can have them replaced. The big advantage of Cokins is availability and price. Btw, Cokin also produce a filter series larger than the P. But more pricey of course. You mentioned Singh-Ray; other brands are Lee and Tiffen. http://www.leefilters.com/ http://www.tiffen.com/ Best, Jostein ----- Original Message ----- From: "Stephen Moore" <[EMAIL PROTECTED]> To: "Pentax List" <[EMAIL PROTECTED]> Sent: Wednesday, September 04, 2002 9:11 PM Subject: Rectangular filter systems > > O Pentaxians -- > > Do any of you use these? > > Lately I've been feeling the need for an ND grad, which > sort of precludes the screw-on approach. The Cokin P system, > at 84mm, seems big enough for most Pentax lenses except the > really big glass and one of the 6x7 lenses that has a 100mm > filter diameter. Singh-Ray seems to favor this size as well. > > I'd be happy to hear comments, praise, damns-with-faint-praise, > caveats, yike-don't-do-thats, etc. from the assembled wisdom. > > Best regards, > > Stephen Moore > >
