Archived posting to the Leica Users Group, 2007/05/19
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]I have a feeling that the best results from this film come from the way that Graham is using it. He's bringing out a partial IR reflectance from the foliage which gives it a nice glow while maintaining the normal visible light view of the low IR reflectance objects like stone and wood. The R25 filter will also add increased contrast to the clouds and sky like normal bw film. The resulting photos have a different look to them which I find very pleasing. And the film seems to be a lot cheaper then Kodak's HIE which is probably a lot more sensitive to infra red. Nice photos, Graham, Len On May 18, 2007, at 7:46 PM, Henning Wulff wrote: > At 7:21 AM +0100 5/18/07, geebee wrote: >> From: "John Biava" <leicam4pro@yahoo.com> >> To: "Leica Users Group" <lug@leica-users.org> >> Sent: Friday, May 18, 2007 12:53 AM >> Subject: Re: [Leica] geebee Ilford SFX processing >> >>> >>> The exact characteristics of the filter you are using also make >>> a big difference. A R 25 is not really an IR filter, but seems >>> to be about all that is readily available now. >>> >> --------------------------------------------------------------------- >> --------------------------- >> John, >> >> I have a Leitz IR filter in 48mm for my 90 cron which I had >> completely forgotten until I read your post so I may have to >> revisit SFX. I think also that SFX just has heightened sensitivity >> to red but isn't a true IR film. >> >> --Graham > > The Leica IR filter is similar in transmission characteristics to > the Wratten 89B, B+W 092, Hoya R72 or Heliopan RG-695. With all you > can see the light source through the filter if you hold it up > toward it (don't do it with the sun!!). This filter is intended to > come as close as possible to dividing the visible from the infrared. > > Heliopan has a series that includes the RG-645 (like the B+W 091, a > dark red) through the RG-665,695,715,780 and 830. The 830 is like > the Wratten 87 or B+W 093; ie, quite dense. > > SFX works with the 89B or Leica IR filters, but has a fairly hefty > speed penalty with that; I forget what as I haven't used that film > but once and didn't bother again. > > With the M8 you can use all the filters. In fact, with all of them > you can just meter as normal and shoot. In fact, the meter is so IR > sensitive you usually have to dial back a bit in the compensation > about 1 stop so that you don't clip the red channel, which is where > all the information is. > > -- > * Henning J. Wulff > /|\ Wulff Photography & Design > /###\ mailto:henningw@archiphoto.com > |[ ]| http://www.archiphoto.com > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information