Very high resolution lens?

[Film-Niko]

Niko

I have not used anything but 400 ASA film for years, except for testing purposes. I wouldn't know what to do with ASA 25. That film speed does not suit my type of photography.

Ralph,

nothing wrong with that. Different photographers, different styles of photography, different types of films with different characteristics. One of the dozens good reasons why using film is so flexible and so much fun: You can always change your sensor .
I do 10-20% of my work with high speed films, rest with lower speed.
And I use the different looks and characteristics of different films to enhance and strengthen the expression of the photograph.

Sometimes an orthochromatic film is the best for my subject, sometimes an orthopanchromatic film (like Spur DSX) does the job best, in other situations a 'normal' panchromatic film is used, and some subjects looks best to my eye photographed with a superpanchromatic emulsion.
Horses for courses.

My photography would be very limited if I were only using Tri-X, TMY-2, Neopan 400 or HP5. I like different film looks for my photography.
And there are no orthochromatic, orthopanchromatic and only two superpanchromatic emulsions with ISO 400.

 

[Film-Niko]

The formula fits well with my experience and testing.
Why are you quoting aerial resolutions which are beyond the hypothetical diffraction limits? At f/8, diffraction limits the lens to 158 lp/mm for red light and 185 lp/mm for green light. This may fit into a research paper but has little to do with practical photography.

Ralph, I referred to the first postings concerning f4, aerial resolution at f4 is about 400 lp/mm with white light. At f5,6 it is about 250 lp/mm.
I am using f2,8, f4 and f5,6 much more often in my daily photography than f8 (f11 is very rare).
Therefore for my style of photography and my lenses it has a lot to do with practical photography.

 

[Film-Niko]

One of them was exactly that: the flexibility of 35 mm format, but at ISO 25?
What flexibility would that be?
Being able to put a small camera with small lenses on a tripod, instead of a slightly larger camera with slightly larger lenses?

No, more flexibility because I don't need a tripod. Adox Ortho 25 and Rollei Ortho 25 are excellent at ISO 32-40 in RLC, T-Max, Diafine (one of the few films which have indeed a bit higher sensivity than the manufacturer, Filmotec, claims).
Rollei ATP is excellent in ATP DC at 32-40.
Spur DSX is best at ISO 50-64 in Spur Dynamicspeed 64.
No problem at all to use these films handheld with f2,8, 4, 5,6 and shutter speeds in the 1/125 - 1/500 range.
I have some photobooks here of the best wildlife photographers: Their preferred films for wildlife (action) shots were Kodachrome 25 and 64 for decades (quite lately Kodachrome was replaced in the nineties by Velvia 50).

TMX was often used by me at ISO 50 developed in Microdol-X. Very good sharpness and resolution, very fine grain, very good tonality.
With Spur DSX in Dynamicspeed 64 I can get the same speed, but much higher resolution (especially with normal and low contrast objects), much better sharpness, and much better highlight detail (this film/developer combination is outstanding in this respect). Very high object contrasts are not a problem anymore.
My experience is similar to the results of Erwin Puts for example (concerning tonality and excellent dynamic range and highlight detail; my resolution values are a bit higher than his):
http://www.imx.nl/photo/Film/page145/page145.html

 

[RalphLambrecht]

Ralph, I referred to the first postings concerning f4, aerial resolution at f4 is about 400 lp/mm with white light. At f5,6 it is about 250 lp/mm.
I am using f2,8, f4 and f5,6 much more often in my daily photography than f8 (f11 is very rare).
Therefore for my style of photography and my lenses it has a lot to do with practical photography.

You are right. Slow films would necessitate these kind of apertures anyway. We are indeed in very different areas of photography. I don't have taken a photograph wider open than f/8 for years.

 

[Q.G.]

No problem at all to use these films handheld with f2,8, 4, 5,6 and shutter speeds in the 1/125 - 1/500 range.

Still, you should try them from atop a tripod sometime.
Your hands shake more than enough to render the calculations we have seen null and void. Even at 1/500.


But seriously: i really don't see the point of using high-resolving films handheld. Shake is huge, compared to the angular resolution you hope to achieve using very high resolution lenses and films.


Apropos use of apertures: i use any aperture i need to get what i want.

 

[RalphLambrecht]

Still, you should try them from atop a tripod sometime.
Your hands shake more than enough to render the calculations we have seen null and void. Even at 1/500.

I agree. In my tests, I had to go as short as 1/250s to get reasonably close to a tripod performance.

Apropos use of apertures: i use any aperture i need to get what i want.

Me too, but f/8-11 gets the most out of my lenses, despite hypothetical diffraction limits. It also helps with my usual MF focusing errors, and when using 4x5, it's f/22 and be there!