Archived posting to the Leica Users Group, 2015/11/24
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]The closest thing I have found to a digital "Tech Pan" type of rendition is the Kolorivision Sulfur ii cover glass for astrophotography. I've put a comparison of the TP v. Kolorivision cover glass spectral responses at http://www.paulroark.com/TechPan-v-Kolorivisio-Sulfur2.pdf . The vertical axes are different, but the general idea, as well as target market, is the same for both the film and now this digital response to the astro group. The Kolorivision cover glass can be put onto a number of cameras, including the Sony a7r. If a normal spectral response is needed from a converted camera, they have a filter for the front of the lens to do that. I did not find a comparable M8 spectral response curve. Kodak has removed the original information from the web. This verbal description of the response curve gives some insight: "...substantial response in the red channel from 650-700nm and continued response out to about 725nm." ( http://diglloyd.com/articles/Infrared/LeicaM8_infrared.html#SpectralResponse) But, it's really a bit too vague to know. It'd assume the response in the 650-700 range is substantially below the TP or Sulfur ii levels. Paul www.PaulRoark.com