Archived posting to the Leica Users Group, 1996/04/18
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]On Thu, 18 Apr 1996, Eric Welch wrote: > I do know that thinner film base means sharper pictures. That's one > reason they use the estar (esthar?) film base with Kodak's TechPan film. > But 120 film being thinner? I don't think so. I suspect it depends on > individual emulsions. The reason 120 looks better is better reproduction > ratios. Because 120 films have a paper backing for support, they can be thinner. I don't know about Kodak films, but Agfa 120 films are about 90-95 um thick, compared to 120 for 35mm and more for 4x5. I don't know how much difference that 25% difference makes to the diffraction effect, but I assume that it means that 35mm filmbase would transmit 25% less light. Now that I think of it, the paper backing might mean that the 120 film could be made out of difference material too, and therefore perhaps more transparent material. I am not sure about that one, though. Hope this helps Gary Toop