Gene, I was looking at the Zeiss review, and it indicates that Fuji Neopan Acros has a slightly higher resolution than Techpan. Its available in 120, as well as 35mm and 4x5. I know I've tried some in the past, but its going to take me some time to hunt down the one roll I shot. It isn't expensive, either. Personally, I just never connect "Fuji" with B&W photography.
"It's the way to educate your eyes. Stare. Pry, listen, eavesdrop. Die knowing something. You are not here long." - Walker Evans
Another experiment I'm going to do soon is determine the resolving power of a couple of FB papers. Ilford FB4 and Kodak Fine art VC.
BTW-I got 156 lp/mm with a pentax 55mm f4, newest version. 168 lp/mm is the diffraction limit at F8. I never saw that with any other films. Not that this matters to most of you.
No Spin Zone-I also do not own any stock in the company.
Fuji Acros rocks. I love that stuff. Even at the price. I just finished loading some Efke 25 ASA that I'll take with me through Tuolumne this saturday if I get to go. Never used it yet. No doubt about it, the Acros is a beautiful film.
Dan, you were wondering why a 400 l/mm film would be important when our lenses can't handle that... basically it's just a matter of sampling the resolution of the lens as well as possible. To be "well sampled" we really need to have data at twice the frequency of the thing we're trying to measure. For a 100 l/mm lens we'd ideally like to have film that can record 200 l/mm just to keep the lens as the weak point in the system. Increasing how well we sample the image isn't a bad thing, but I'm not sure that it gets us a tremendous amount more. It makes me think of point and shoot digital cameras: who cares if you have a 7 megapixel image if there's only 3 megapixels worth of information. You might as well increase the size of the pixels and get less noise and more sensitivity.
I should add a disclaimer though. I only shoot HP5+ in my 4x5 and all my experience in sampling images comes from my work. I'm an astronomer specializing in crowded field photometry. Using a 2.4 meter telescope and cryogenic cameras is a little bit different than taking my canham into the woods.
Gene: What, I'm not the only one who leaves eyeball prints on photographs? Great! BTW, when I was at the Gigabitfilm site and looked at their little article about 4x5 vs 35mm, I picked the 4x5 picture correctly! Mind you, it wasn't easy. What gives away the 35mm is the end of the wood support in the lower-right corner, and a couple of other fantastically minor points.
When it comes to spending over $2/sheet for film, the application has to really justify it for me to part with my dough. On average, B&W sheet film is a bit less than $1/sheet. I think that's reasonable. Techpan is $2/sheet, but $3/sheet for Gigabitfilm can't be justified for what I want to do.
Oh, yeah: When you do the paper resolution test, you might want to replace Kodak with a different paper. After all, Kodak doesn't have that B&W lovin' feelin' like they once did.
"It's the way to educate your eyes. Stare. Pry, listen, eavesdrop. Die knowing something. You are not here long." - Walker Evans
Efke 25 is extremely fine grained and sharp. The color sensitivity is on the opposite side of Technical Pan though (Technical Pan is super-panchromatic while Efke 25 is orthopanchromatic). Use an orange filter, and the results will look more like Tech Pan.
Efke 25 can be developed in any standard developer.
Gene, Nathaniel, thanks very much for the explanations.
Gene, its useful to know what you're doing. I shoot 2x3 roll film, typical shooting aperture is f/16. F/11, at times, for lenses made for much larger formats, f/22 for lenses that need it. Almost always from tripod. Not to quarrel, but although I can see the benefits of very high resolution film for people shooting smaller formats, on 2x3 or larger they're not obvious. You tried, I'm dense.
Nathaniel, you gave me a rule of thumb. It doesn't agree well with the ideas presented in John Williams' book Image Clarity. Nice rule of thumb, but why should I believe it since Williams' prescriptions seem to work?
I actually use some lenses that are diffraction-limited wide open. Zeiss Luminars, to be exact, and not generally usable.
On the whole, the search for sharper film and lenses strikes me as having very little to do with photography. People have made fine images using the photographic process for over a century and a half. And they've done it with soft lenses, soft films, soft paper.
There are many many ways to lose the image quality our gear can deliver. It seems to me that trying to improve image quality by improving technique or by moving up in format is more productive than just buying better gear for the same old format.
Further along those lines, Gene, like you I'm a somewhat compulsive tester. The lenses I've tried out in a focal length separate into two heaps, "don't use if better is available" and "ok." Differences between the two groups are large and striking, within the "ok" group they're small and not always reproducible. Good lenses are all pretty good. Bad lenses stand out from the crowd, good ones don't.
Cheers, thanks again,
Brian. Welcome to the compulsive grain club. We meet 3 times a day at the nearest 20x24 print washer. Bring your 25X loupe. Nikon/Zeiss microscopes are always welcome.
I'll try and run down some Acros this week and take another roll of pictures of the church across
the street. I'll load up the hassie/80 mm and shoot six exposures and roll it up, reroll it in the darkroom and shoot the last 5 shots with the pentax 67/55mm lens. Who said I was't cheap?
Seriously, me new bride of 7 years is working hard to get the word "Cheap" out of my thoughts and speech. I turned the first corner, in 1999 when I told her I'd always wanted a Hasselblad and she says, "go get one". I progressed in the next year to "I'm thinging about getting another fake rolex" and she says " get a real one". In the last year, I said "think I might buy another Rolex" and she says "get two with diamonds for both of us" No wonder I love her so much:>)
I'm signing off and I will be back with my impressions of Acros. If it works out I have about 10 rolls of Tmax and 15 rolls of Ilford Delta 100 that I will sell cheap. D_mnit, its back again!!!!
Cheers and keep the dirty side down!
Just a little update: I printed my lens tests last night.
8x10: Bicycle wheel in window is visible, but you have to know where to look.
11x14: Spokes on wheel are visible under magnification. High contrast bricks are individually discernable.
16x20: Spokes are visible without magnification, nose-to-print distance three inches. High contrast bricks are easily individually discernable.
20x24: Spokes are visible, and this is as far up as my D3's head will go. If I want larger, I have to swing the turret around and project on the floor, or else attach the right-angle mirror and project on the wall.
Here there be no grain, laddie boy!
"It's the way to educate your eyes. Stare. Pry, listen, eavesdrop. Die knowing something. You are not here long." - Walker Evans
I made a comparison between old rolls of tech pan and new ones, and found the old ones usable and more than that.
http://www.covingtoninnovations.com/...an-drucker.pdf
So I think we shouldn't look for substitues so early. Many people, including me, still have large stocks of these old rolls for sale, not only in 35mm format but in many other larger formats. I suggest using those instead of looking for inferior substitues. This film, by the way, is undoubtedly irreplaceble for astrophotography uses.
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