Best Combination of Film and Developer for Sharpness?

[RalphLambrecht]

Gerald

As Nicholas said, sharpness is subjective, but it is compiled of measurable components such as resolution, acutance and contrast. These component are effectively combined to a modulation transfer factor (MTF). Grain is a noise factor, because it affects resolution. However, with 4x5, grain only has a marginal influence.

I'm not aware of acutance developers affecting overall gradation. Maybe they do on a micro level. Again, with 4x5, I don't see an issue.

 

[dpgoldenberg]

Here is an overview over the resolution abilities with high contrast details in lines per millimeter of some (already mentioned films) as an orientation, how "sharp" you can get. These numbers are in reality (with normal, pictoral contrast) a lot lower, maybe only two thirds:

Best,
Andreas

Andreas,

Can you tell us where these numbers come from?

Thanks,
David

 

[RalphLambrecht]

Andreas,

Can you tell us where these numbers come from?

Thanks,
David

I suggest not to get hung up on these resolution values. First of all, image resolution is a combination of lighting, film, camera lens, development, enlarger lens and paper. So looking at idealized film resolution values means little. To determine image resolution, the entire imaging system must be considered. And second of all, contrast is more important for sharpness than resolution anyway.

A high-contrast, low-resolution system will deliver a sharper image than a low-contrast, high-resolution system.

 

[A49]

Andreas,

Can you tell us where these numbers come from?

Thanks,
David

I fetched them from a post in a German forum. A source was not given there. As I said, the numbers are only a rough guide about the resolving potential of the films.

The best I ever reached in terms of resolution during 15 years of shooting (not laboratory tests) is a negative which resolves about 160 lines per millimeter. I could "count" that because there was a very small label in the picture with the letter "E" which are vertically five bars. The neg is done with Technical Pan and Technidol in the field. The resulting picture is both: very detailed and also very sharp due to the Technidol development. The 12x16 inch print looks as if a pretty good MF negative was the source but it is in fact only from a 35mm film.

That is a good example what a film-developer-combination can do if the other factors are also good enough to exhaust the given potential.

In "normal" photographic live with real pictures done in the field, resolutions on film about 100 lines per millimeter in 35mm and MF and about 60 lpm for LF are very, very good. The film-developer-combination is often not the limiting factor for the resolution at least if you shoot with the new (T-grain) films. For the sharpness impression in a print it is another story, as was already explained a few times in this thread...

Best,
Andreas

 

[RalphLambrecht]

... The best I ever reached in terms of resolution during 15 years of shooting (not laboratory tests) is a negative which resolves about 160 lines per millimeter. I could "count" that because there was a very small label in the picture with the letter "E" which are vertically five bars. ...

Andreas

As how many lines (as in lines per mm) did you count the five bars?

 

[2F/2F]

T-Max 100 in T-Max or X-Tol developers (and a heavy duty tripod) if that really if your most important criterion.

 

[Q.G.]

Looking at the numbers in this thread, or rather the "lines per mm" thing mentioned each time numbers are mentioned, something here is wrong.
And it probably is the "lines per mm" thing: "lp/mm" stands for "line pairs per mm", not "lines per mm".
The numbers begin to make sense when they are line pairs per mm. Too low if only lines per mm.

I don't know, of course, what the source for the numbers was, but Zeiss published some data quite a while ago in their publication "Camera Lens News", and those are repeated now and again on the net.

 

[pgomena]

The OP asked for film/developer combination that would give him good sharpness and good latitude for expansion/contraction. He apparently is a student.

Of the films he listed, I would recommend FP4+. Of all the myriad developers available, I would suggest X-tol used as a replenished system. FP4+ will give him a film with good resolution and sharpness and plenty of latitude for expansion/contraction experiments. X-tol used in a replenished system will give him good sharpness, film speed and economy. The slow, high-acutance films, ortho films, etc., are pretty tough for a beginner to control. Better to start with a more traditional emulsion and learn how it behaves.

Peter Gomena

 

[olwick]

In my opinion (and yours may vary) the definitive text on sharpness and b&w film is this book: 'Edge of Darkness: The Art, Craft, and Power of the High-Definition Monochrome photography' by Barry Thornton http://amzn.to/9bq4RT

As others have said, it's more than just the film and developer.

Mark

 

[A49]

Andreas

As how many lines (as in lines per mm) did you count the five bars?

I counted them as five lines and multiplied with the magnification factor. That seemed to be intuitively logical to me.

Andreas

 

[A49]

The numbers begin to make sense when they are line pairs per mm. Too low if only lines per mm.

This is an important point. I think the numbers are for lines per millimeter (lpm) not line pairs(lppm). This fits to resolution numbers for lenses that I know and to that what I can see in some of my negatives. Else my best lens resultion test negatives would only be half as good as they theoretically should be. But as I´m not totally sure, I like to ask the experts and maybe they who have read some of the recommended literature, which is right.
Andreas

 

[A49]

The numbers begin to make sense when they are line pairs per mm. Too low if only lines per mm.

Just to add: If I look at the MTF chart in this tech. pub. for TMAX 400: http://www.kodak.com/global/en/professional/support/techPubs/f4043/f4043.pdf

Regarding that I would also speak for lines per millimeter since at 80 cycles per millimeter which for me are analog 80 lines per millimeter the curve is already below 50 % and I don´t think it will make it to 400 cycles per millimeter which would be analog for TMAX 400, if the numbers in the table I posted are true and were for line pairs per millimeter.

Andreas

 

[A49]

The numbers begin to make sense when they are line pairs per mm. Too low if only lines per mm.

...and to add one argument more for lines per millimeter: In the FUJIFILM Professional Data Guide from 2002 Fuji tells the resolving power of their films but unfortunately only for colour negative and colour slide. The best resolving film there is the Velvia with ISO 50: resolving power at 1.6:1 - 80 lines/mm and at 1000:1 - 160 lines/mm. As the numbers in the posted table are for the high contrast (1000:1) it would imply that b/w films are about twice as good in resolution as colour slides are, in case the numbers stand for line pairs and not only single lines.

Andreas

 

[RalphLambrecht]

I counted them as five lines and multiplied with the magnification factor. That seemed to be intuitively logical to me.

Andreas

Andreas

Sorry to burst your bubble, but this is not correct. Both terms 'lines per mm' (l/mm) and line pairs per mm' (lp/mm) mean exactly the same. You can either count the white lines of a target, the black lines, or the number of pairs but not black and white lines together. In some papers or optical measurement reports one often sees the more scientific term 'cycles per mm', which comes from the modulation transfer of a sinusoidal traget, which translates directly to lp/mm. If you see a resolution listed in l/mm, it's just shorthand for lp/mm.

So, your letter 'E' has two white and three black bars. This means, your resolution measurement was based on 2.5 lp/mm (or l/mm if you like) not 5. If this means that the highest resolution you have ever achieved is not 160 lp/mm but 'only' 80 lp/mm, don't worry, that's quite normal for a very good system resolution.

 

[Q.G.]

This is an important point. I think the numbers are for lines per millimeter (lpm) not line pairs(lppm). This fits to resolution numbers for lenses that I know and to that what I can see in some of my negatives. Else my best lens resultion test negatives would only be half as good as they theoretically should be. But as I´m not totally sure, I like to ask the experts and maybe they who have read some of the recommended literature, which is right.

Well no.
The figures are decidedly too low for lines per mm.
Lens resolutions for half way decent lenses are also way up, in the region of 100 to 200 line pairs (!) per mm.
Zeiss' ZF f/1.4 50 mm resolves 320 line pairs per mm. And Zeiss' Biogon f/2.8 25 mm ZM lens actually allowed counting up to 400 line pairs per mm (recorded on SPUR Orthopan UR film). That's 800 lines per mm.
But that's a particular good lens.

Just to add: If I look at the MTF chart in this tech. pub. for TMAX 400: http://www.kodak.com/global/en/professional/support/techPubs/f4043/f4043.pdf

Regarding that I would also speak for lines per millimeter since at 80 cycles per millimeter which for me are analog 80 lines per millimeter

Well there you go. A cycle is pair of two lines.
So 80 cycles is 80 line pairs, not 80 lines.

Don't get hung up on MTF performance. A lens will resolve, say 160 lp/mm, even if the contrast at that frequency is reduced to 5%.
Only at 0% MTF performance can it be said that a lens doesn't resolve the particular spatial frequency, at which the contrast drops to 0.


Film's capabilities are rather better than what you think also.
As mentioned above, SPUR's orthopan was able to reproduce an impressive amount of detail. But that was shooting test targets.
In real life scenarios, a 'normal' film like T-Max will record up to 180 line pairs per mm. Portra about 140 - 160 line pairs per mm. Ektachrome 100 VS did manage 130 line airs per mm.
And if we are to believe the source of these figures (Zeiss again), that was not measured shooting high contrast targets.

Sorry to burst your bubble, but this is not correct. Both terms 'lines per mm' (l/mm) and line pairs per mm' (lp/mm) mean exactly the same. You can either count the white lines of a target, the black lines, or the number of pairs but not black and white lines together. [...]

I'm sorry Ralph, but you can.
Line pairs per mm are definitely not the same as lines per mm.
You can count lines, as a measure for the smallest detail an optical system can render.
You can count black and white line pairs, i.e. two lines (what else would "pair" mean?), to help you determine how good that optical system can render that fine detail.

You're only counting the white lines, skipping the black spaces separating them, however is the same as counting both "black and white lines together". You just forget to mention that there are black lines between the white ones.
The result is the count of line pairs per mm.

 

[A49]

Well no.
The figures are decidedly too low for lines per mm.
Lens resolutions for half way decent lenses are also way up, in the region of 100 to 200 line pairs (!) per mm.

That suprises me, because it seems to be far away from the things I can see on my films. But I´m ready to accept it. It should mean for me that I´m only on the half way and not at the limits, which would be good.

In real life scenarios, a 'normal' film like T-Max will record up to 180 line pairs per mm. Portra about 140 - 160 line pairs per mm. Ektachrome 100 VS did manage 130 line airs per mm.

Did you ever see something in this resolution´s regions on film, equal if test target or real life´s fine detail? Because the 200 lpm (which is very near to your claimed 180 lpm) for TMAX 100 are definitely for 1000:1 and at 1.6:1 you would have only about the half, so for a pretty usual 100:1 scene I would suggest a resolving power not over 150 lpm for this film.

Line pairs per mm are definitely not the same as lines per mm.

If your true at this and I would hope that for me, because else some other resolution numbers I have in mind as cornerstones would crumble, then there would be a huge confusion in the literature, the producer´s tech pubs and the internet anyway. As I said the FUJIFILM brochure definitely speaks of lines/mm (In German: "Linien/mm") and claims 160 of that for Velvia at 1000:1.

Then I have an very useful book full of photographic charts and figures. There is a very interesting one about the theoretical maximum resolving power of lenses at a given aperture - the perfect lens only limited by diffraction due to the apertures size. For instance for f/2.8 (and 486 nm wavelength of the arriving light) it says 590, for f/4 it says 417 and for f/22 only 75 lines per millimeter ("Linien"). If that was really lines and not pairs then the Zeiss' Biogon f/2.8 25 mm with 400 line pairs must have beaten the diffraction limit...

So I think, and here I must accept again, that I have to revise some resolution facts in my mind, that when you read "lines per mm", it really means the same as line pairs per mm. As Ralph has said.

Andreas

 

[Q.G.]

Did you ever see something in this resolution´s regions on film, equal if test target or real life´s fine detail? Because the 200 lpm (which is very near to your claimed 180 lpm) for TMAX 100 are definitely for 1000:1 and at 1.6:1 you would have only about the half, so for a pretty usual 100:1 scene I would suggest a resolving power not over 150 lpm for this film.

I'm not in the habit of examining film under a microscope, counting line pairs, so i trust Zeiss in this.
See here, or here.

Zeiss don't make film, and have no reason (other than giving us a reason to want their expensive lenses) to exagerate the performance of films they tested in 'real life' situations.

If your true at this and I would hope that for me, because else some other resolution numbers I have in mind as cornerstones would crumble, then there would be a huge confusion in the literature, the producer´s tech pubs and the internet anyway. As I said the FUJIFILM brochure definitely speaks of lines/mm (In German: "Linien/mm") and claims 160 of that for Velvia at 1000:1.

Then I have an very useful book full of photographic charts and figures. There is a very interesting one about the theoretical maximum resolving power of lenses at a given aperture - the perfect lens only limited by diffraction due to the apertures size. For instance for f/2.8 (and 486 nm wavelength of the arriving light) it says 590, for f/4 it says 417 and for f/22 only 75 lines per millimeter ("Linien"). If that was really lines and not pairs then the Zeiss' Biogon f/2.8 25 mm with 400 line pairs must have beaten the diffraction limit...

So I think, and here I must accept again, that I have to revise some resolution facts in my mind, that when you read "lines per mm", it really means the same as line pairs per mm. As Ralph has said.

Fuji does appear to mix the two, giving resolution numbers in lines that equate to cycles (i.e. line pairs) in their MTF graphs.
And line pairs per mm (a pair of lines, i.e. two lines) indeed is the correct unit to use in linespread functions (the things MTF curves are representations of). And i can't remember ever seeing the same lp/mm numbers used as if they were l/mm anywhere except this thread (and Fuji).

So i'll stick with Zeiss in this too.

By the way: have you calculated the resolution limit using the formula you must also have found in that book?

 

[lensworker]

I cast my vote for Kodak Tri-X and D-76.

 

[A49]

By the way: have you calculated the resolution limit using the formula you must also have found in that book?

Unfortunately the book only comprises charts and more charts. As I believe Zeiss in talking about the f-stop dependend resolution limits due to diffraction, the only explanation is, that my book says "lines" and means line pairs in the according chart. There is a big circle of confusion around resolution issues. I hope that I can downsize mine by reading this recommended "Image clarity" book which I have ordered at my library. I also hope to find there the answer to the (now bigger than before this discussion) big question, how far one can go with resolution, especially in large format. I admit that I have only 30 to 40 lpm there in my "sharpest" sheet films, which is about the half of the theoretical maximum at f/22 and slightly lower in comparison to usual values in this LF lens testing chart http://www.hevanet.com/cperez/testing.html.

Andreas

 

[A49]

Andreas, do you know what would be the numbers for Kodak Tech Pan?

By chance I found here another set of resolution numbers that include the Tech Pan :

New Film Resolving Power Data
Kodak Supra 800: 80 lp/mm
Maco Ortho PO 100: 80 lp/mm
Kodak Tech Pan: 140 lp/mm
Kodak Supra 400: 100 lp/mm
Fuji Neopan Acros 100: 160 lp/mm
Kodak Farbwelt 100: 160
Kodak Farbwelt 400: 160
Fujichrome Velvia 100 F: 170
Gigabitfilm: 400

Best regards,
Andreas

 

[RalphLambrecht]

... I'm sorry Ralph, but you can.
Line pairs per mm are definitely not the same as lines per mm. ...

You are right on both accounts. What I meant to say was that one should refer to resolution in cycles or line pairs per unit to get to comparable resolution values and avoid confusion. lp/mm and l/mm are obviously not the same, but unfortunately they are often (wrongly) used in interchangeably.

 

[Q.G.]

[...] I admit that I have only 30 to 40 lpm there in my "sharpest" sheet films, [...]

Andreas, the circle of confusion expanded hugely when you introduced that new "lpm" concept. Lines per meter? Or line pairs * meter (i.e. the total number of line pairs on a stretch of a variable amount of meters long)?
:confused:

 

[richard ide]

AFAIK line pair refers to 1 black and 1 white.

 

[RalphLambrecht]

AFAIK line pair refers to 1 black and 1 white.

Indeed, and that's were some are confused. If you draw a few lines, equally spaced, on a sheet of paper, you would normally count the number of lines drawn but not the resulting, imaginary white lines in between them.

Let's assume you've drawn five 0.1mm thick lines, 0.1 mm apart from each other. The result is a frequency (or resolution) of 5 line pairs per mm (lp/mm). If you only count the black lines, you get 5 lines per mm (lines/mm), and if you count black and white lines, you get a resolution of 10 lines/mm.

Some researchers would report the above as 5 lp/mm, some as 5 lines/mm, and some as 5 cycles/mm. I've never seen it reported as 10 lines/mm.

 

[A49]

Andreas, the circle of confusion expanded hugely when you introduced that new "lpm" concept. Lines per meter? Or line pairs * meter (i.e. the total number of line pairs on a stretch of a variable amount of meters long)?
:confused:

After having anybody else confused, I at least see clearly.

Lets say so: the synonymous usage of lines per mm and linepairs per mm is not intuitively understandable for everybody. To find out about this I consulted 3 or 4 general photographic books and wikipedia as well, that all explained resolution and the measurement of it with b/w line patterns and said that is indicated in lines per mm or line pairs per mm, but none of them explained, what lines per mm do exactly mean and that it is the same with lp/mm. On the other hand the expression line pairs/mm can not be misunderstood easily and in my opinion should be prefered.

Andreas