Archived posting to the Leica Users Group, 2006/11/25
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Henning, I've done no IR at all, ever. In reading comments I notice that there are often lens scales showing IR focusing differences. Does this vary from lens to lens? Is there a way to compute the difference and create a spreadsheet or do I do it manually and make a table of results? Does the setting for infinity change? Longer wavelengths focus closer or further than visible light? I don't remember and my mind can make reasons why its either. Thanks for answering basic questions. Adam On 11/25/06, Henning Wulff <henningw@archiphoto.com> wrote: > At 10:10 AM -0500 11/25/06, Leonard Taupier wrote: > >Simon, > > > >I don't think Edwin's comments or M8 evaluations exactly address > >what Jim Christie asked. > > > >First off, using a RF camera like the Leica M is easier than with a > >SLR. The IR filter can stay on the lens without obstructing the view > >of the scene. IR film is more sensitive than a digital sensor so > >hand holding the camera is more of a possibility with film. With the > >digital SLR you need to either frame and focus the scene with the > >camera on a tripod and with the filer removed, or prefocus and use > >an external viewfinder with the filter on. > > > >IR sensitivity of current digital cameras can vary from so so to not > >at all (Nikon D200). > > Actually I found the IR sensitivity of the M8 to be not much > different and possibly even greater than that of Kodak HIE, the most > common high sensitivity film. The shot I showed was handheld at > f/8-11 at 1/30 sec at 1250 ISO with an 87 filter. With Kodak HIE > you'd be a couple of stops down with an 87 filter. With an 89b filter > the sensitivity of the M8 was similar to that of HIE, but at the > longer wavelengths that the 87 passes the M8 was more sensitive. > > It's a little bit hard to compare because the spectral responses are > different at different wavelengths, and also I didnt't really have > enough time to do a thorough job. Most of my time with it was just > taking pictures and trying things out to see if it met my > expectations. Which it did, and more. > > >In order to take images at all one must set the ISO very high (800 > >or higher), hope you get an image at all and live with the > >resulting grain. The resulting image must then be converted to > >monochrome or desaturated and the contrast increased for acceptable > >IR photos. > > > >Henning shared an IR photo with us that was taken with an M8, > >handheld and at a lower ISO than what can generally be taken with > >the current digital cameras. It was a beautiful image, sharp, very > >good depth of field and lower grain than what I normally see from > >film. I may be wrong but from memory I believe it was taken at ISO > >640 (or so). The short answer to Jim's question is YES. > > > >Len > > > > > >On Nov 25, 2006, at 3:56 AM, animal wrote: > > > >>Hello, > >>Erwin Puts article on the subject as well as his second review of the M8 > >>http://www.imx.nl/photosite/comments/c029.html > >>http://www.imx.nl/photosite/leica/M8_2/t007.html > >> > >>seasons wishes > >>simon jessurun > >>amsterdam > >>the netherlands > >> > >> > >> > >> > >> > >>----- Original Message ----- From: "Jim Christie" > >><jim.christie@sbcglobal.net> > >>To: <lug@leica-users.org> > >>Sent: Friday, November 24, 2006 8:34 PM > >>Subject: [Leica] M8 & Infrared Photograph > >> > >>>I've been trying to follow and understand the problem issues with the > >>>new M8 > >>>and I have the following question. Does the IR problem mean that the M8 > >>>is > >>>more sensitive to IR light and, therefore, if you shoot for Infrared > >>>photographs without the proposed filter and use a normal IR filter > >>>instead, > >>>will one get more Infrared light and possibly better IR photos? > >>> > >>>Jim Christie > >>> > >>> > >>> > >>>_______________________________________________ > >>>Leica Users Group. > >>>See http://leica-users.org/mailman/listinfo/lug for more information > >> > >> > >>_______________________________________________ > >>Leica Users Group. > >>See http://leica-users.org/mailman/listinfo/lug for more information > > > > > >_______________________________________________ > >Leica Users Group. > >See http://leica-users.org/mailman/listinfo/lug for more information > > > -- > * 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 >