Hello Mishka I admit to not having printed the taget in 600ppi, just 300ppi on an office printer - so the target is a bit "rusty". (I am consiodering odering an "official" test sheet (19 USD), showing all 5 or 9 USAF tagets on the same poster).
The print quality of the tagets is's on source of error. Annother one is the fact, that I don't know how to calculate the results from a "55 times Focal Length" distance, since I'm actually looking at a factor 1.5 crop (a 50mm lens gives a FOV equal to a 75mm on film). I guess the 55 times rule don't apply here. Nevertheless, if I change the calculations, I still get very poor resultion compared to the 98 lpm that this is know to achieve on film. Anyway, it's not possible to actaully PRINT 98 lpm from a neg. Only the film (or slide) can produce this kind of resolution. So, I guess in practice the difference between a print made from film or 6 Mp CCD, using the same lens, isn't all that different. Il, give it a try sometime. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -----Oprindelig meddelelse----- Fra: Mishka [mailto:[EMAIL PROTECTED] Sendt: 2. november 2004 13:24 Til: [EMAIL PROTECTED] Emne: Re: USAF target and resolution tests Jens, Either your lens has its *every* element sanded, covered with vaseline and reversed, or people who claim passable 11x14 from *istd are blind. Or both. Mishka On Tue, 2 Nov 2004 04:44:42 +0100, Jens Bladt <[EMAIL PROTECTED]> wrote: > Thanks Rob. The spreadsheet is very usefull. It's seems my 1.4/50mm resolves > no more than 20-30 lpm when used on the *ist D. > > > Jens Bladt
