Infra red filters

[John_K]

I don't mean the Wratten 25 deep red, but the opaque filter version. I bought a SFX kit which came with a gelatine I/red opaque filter in a mount that fitted the Cokin 'P' holder. It works well too with my 28/105 Nikkor. However the gelatine filter is held in a sub mount which gives extreme vignetting when I use it with my 17/35 Nikkor Is there anyone who produces a 'P' size IR opaque filter that slides into a cokin mount with no sub mount

[beejaybee]

Is there anyone who produces a 'P' size IR opaque filter that slides into a cokin mount with no sub mount

I suspect you may be better off looking for a filter that screws directly into the filter thread on your lens. They're not cheap. For SFX you probably want the B+W 092 rather than the 093 which may not pass enough "short" infra red to activate the film.

[John_K]

No there is no vignetting with a normal 'P' series Cokin and I use these regularly I was just trying to find out if anyone made one with the opaque I/R filter. The one that came with the SFX, the overall mount is the same as a cokin filter, but the actual gelatime filter part itself, is in a circular aperture only appox 60mm in diameter. Not even as big as the FRONT element of the 17/35

[Nod]

Just measured the aperture of my SFX filter for Cokin P and it's 75mm across. Not quite big enough for the blu-tak, although you might get away with it.