Archived posting to the Leica Users Group, 2003/04/12
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Oliver Bryk wrote: > > Results of testing the resolving power of several films with actual > photographic lenses (rather than by the film manufacturers' laboratory > procedures) are reported in "Camera Lens News #19" at www.zeiss.de . Some > examples are: T-Max 100: 180 line pairs per millimeter; Velvia: 160 lpmm; > Portra 400 b/w and Portra 160 VC: 150 lpmm. > Oliver Bryk > > -- > To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html It said 200 lmpp was the surprise at a trade fair a few years back with ASA 25 films, Agfapan 25 and Ektar 25 color neg film from Kodak. Both gone but now we have t grain type technologies and medium speed films resolving at 180. T-Max 100. And 180 I can live with that's close enough for me. Ansel Adams was putting Tri X in his Hasselblads for peet sakes which resolves at what? 90 would be my guess. I'd have loved knowing how Ilfords old Pan F (ASA 50) stood up againt the modern medium speed t grain like films: Delta 100 and Fuji Neopan Across 100. My guess is it would slightly edge them out. I'd also like to know what they ran the black and white film in. I'd hope it was Beutlers. Rodinal would be OK. But not a high solvent developer not highly diluted. Interesting at the bottom on the list but ON the list are the C41 800 films, Fuji's NPZ 800 and Kodaks Portra 800. Both straddling the 100 line pairs point which i believe was once thought of as the sound barrier. 800 speed films! And this and the 400 speed color neg films is where all the R&D is at. A mystery why Kodaks C41 Portra 400 B&W resolves at 150 beating out or matching a slew of medium speed films. A top lens company checking out where the films are at. It's been expressed that lenses are not made to better the films they are used with. Or maybe it was films were not made to be better than the lenses they work with. Anyway there is said to be relationship. I think what that relationship is is not obvious to us outsiders. But it could be there is no relationship. That the films companies do the best they can and so do the lens companies and it doesn't seem that either are wasting their time. That is the films companies are not making films that resolve much higher than any lens or visa versa. It all seems to work out fairly closely and nobodies wasting their time. And i think that one of the few instances of coincidence that i believe in. Between the chemical and the optical worlds. Mark Rabiner Portland, Oregon USA http://www.rabinergroup.com - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html