Yes, I agree. In a followup posting, I mentioned that I could use a sacrificial Chinese ND8 solid cokin filter for this, as I thought about the flare. Even darker would be better, but I don't know if there are knock-off ND400s. Probably there are. And, all of my lens' filter diameters are 49mm, so using the cokin P system @ 84mm should be OK. And if I could slide this panel into the first slot, I think I could still use a 49mm round filter. Probably not with super wide, but I usually only use about a 28mm lens, and that's with an APC sensor. If I go to a full-frame, 28mm may be too wide for this arrangement. When I can afford a full frame, I'll let you know. :) Andrew On Tue, January 29, 2013 7:04 pm, Louie Powell wrote: > I agree with James - get a sacrificial filter and remove the glass, > retaining only the metal ring. Then, get a sacrificial Cokin filter and > cut a hole in the center. Glue the metal ring in place. After the glue > cures, you can then screw any conventional filter you want into this > 'utility > mount'. > > Two concerns. First, flare. The ideal sacrificial Cokin filter is one > that is nearly opaque so that light cannot enter through the Coking filter > and then bounce around between the ad hoc filter and the lens. If nothing > else, perhaps apply a little black paint to opaque the area surrounding > the mounting ring. > > Second, if I were doing this, I think I would select a glass filters > (both > the sacrificial filter from which I cannibalize the metal ring and the > filters that I would use with this setup) that are at least one standard > size larger than the front diameter of the lens on the camera. I would > worry about this setup causing vignetting, and oversizing the filter > would tend to avoid that problem. > > -----Original Message----- > From: owner-photoforum@xxxxxxxxxxxxxxxxxx > [mailto:owner-photoforum@xxxxxxxxxxxxxxxxxx] On Behalf Of James Schenken > Sent: Tuesday, January 29, 2013 9:41 PM > To: List for Photo/Imaging Educators - Professionals - Students > Subject: Re: cokin slide-in adapter for traditional lenses? > > > Andrew > > > What you are describing is a traditional lens board with a threaded hole > in the center. The easiest way is to use a sacrificial Cokin filter with a > carefully centered hole and a filter ring cemented into place. > > Of course, any suitable piece of material would do if the thickness was > correct and the size the same. > > > > On Jan 28, 2013, at 11:59 PM, asharpe@xxxxxxxxxxxxxxxx wrote: > > >> Hi folks, >> >> >> I wonder if anyone has ever invented a slide-in adapter for the cokin >> series that had threads for traditional filters? >> >> I know that that problem is exactly what the filter system is trying >> to solve, not needing separate sizes of filter for multiple lenses, but >> the fact is, sometimes (usually?) traditional filters are of much better >> quality than the cokin filters. Specifically, I'm thinking about the >> cokin polarizers, which are unimpressive. I already have some very good >> screw-in polarizers, but I'd like to use the cokin system for my ND >> grads, and a screw-in polarizer on the lens with the cokin system in >> front of it is clumsy at best, unusable at worst. >> >> It seems that a simple slide in card with an appropriately-sized hole >> with threads would be very useful. So, does it exist? If not, perhaps I >> can convince folks with a kickstarter project. >> >> Andrew >> >> > > >
