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formanproject
6-Nov-2017, 17:47
Does anyone know why medium format and large format film supposedly handles dynamic range and overexposure better than 35mm film? Essentially it's just like a cropped in portion of a medium or large format negative, so why would it handle light any differently?


I understand why it would have a more 3D look due to more tonal information and a more gradual gradation of tones, but density and overall dynamic range should be static, no?

Leigh
6-Nov-2017, 18:01
Does anyone know why medium format and large format film supposedly handles dynamic range and overexposure better than 35mm film?
Who said it does?

I shoot all formats from 35mm through 8x10.
I've never seen any difference using the same film and processing with different formats.

- Leigh

mdarnton
6-Nov-2017, 19:04
One of my favorite reasons I can't get into digital herewith tendered for your consideration: https://www.flickr.com/photos/mdarnton/6929081535/in/dateposted/

35mm Tri-X, seventeen stops of range measured, from under the desk to the white wall outside. There never has been a problem with dynamic range in film; the film is not the problem, easily getting it printed on photo paper is. Now that I convert film to digital for everything, pix like this, which use to be a PITA to print, are easy as pie.

mdarnton
6-Nov-2017, 19:04
One of my favorite reasons I can't get into digital cameras, but love scanning film, herewith tendered for your consideration: https://www.flickr.com/photos/mdarnton/6929081535/in/dateposted/

35mm Tri-X, seventeen stops of range measured, from under the desk to the white wall outside. There never has been a problem with dynamic range in film; the film is not the problem, easily getting it printed on photo paper is. Now that I convert film to digital for everything, pix like this, which use to be a PITA to print, are easy as pie.

jp
6-Nov-2017, 20:10
All things being equal there should be no difference between sizes.

LF has an advantage in that sheet film could be developed to make that dynamic range more printable, by custom developing each sheet

Scanning is great for getting big dynamic range out of any negative.

MF/LF, at least with older lenses have more iris blades than most 35mm except 35mm is starting to catch up with that with the newest lenses; things like the sun can maintain their shape without turning into a blob the shape of the iris. With digital you wouldn't have the sun in a photo. If you did shoot the sun with digital, it'd be blown out pretty good and maybe be a starburst rather than a round shape because that's common for the lenses that go with digital cameras. With an old tessar and MF/LF you can have tons of blades for a wide open look at any aperture and only three chunks of glass so not much reflections/flare if things are clean.. This is with my 4x5 RB-Super-D; I do similar with a TLR.

https://farm9.staticflickr.com/8495/8340646826_0fefe7c7d0_z.jpg (https://flic.kr/p/dH2ZHC)
img948 (https://flic.kr/p/dH2ZHC) by Jason Philbrook (https://www.flickr.com/photos/13759696@N02/), on Flickr

Doremus Scudder
7-Nov-2017, 03:42
The problem with overexposure is that it increases graininess. With larger-format film, this is less of a problem. With 35mm, you really want exposure to be the minimum needed to retain the shadow values you need. Many (me included when I shoot smaller formats) like to develop smaller film to a lower contrast index and print on higher contrast-grade paper (or with higher-contrast filtration) to minimize the grain as well.

The films, regardless of size, react the same, it is just the degree of enlargement that makes optimizing things for smaller formats more important.

Best,

Doremus

Pere Casals
7-Nov-2017, 06:19
Does anyone know why medium format and large format film supposedly handles dynamic range and overexposure better than 35mm film? Essentially it's just like a cropped in portion of a medium or large format negative, so why would it handle light any differently?


I understand why it would have a more 3D look due to more tonal information and a more gradual gradation of tones, but density and overall dynamic range should be static, no?

Different formats of the same film do handle light in the same way.

Let's see something... http://imaging.kodakalaris.com/sites/prod/files/files/products/f4016_TMax_100.pdf

Here Kodak has a single specification for all formats, same characteristic curves for all formats in page 8.

But... in that page you see a couple characteristic curves depending on development time.

With sheet film you have an advantage over roll film, you can develop/agitate different time for each single sheet, so you can cook every scene in an special way to make fit scene dynamic range in the usable density range.

At the end with sheets you pick a curve of the family shown in the chart. This is the "stellar" Zone Sytem, you cook N-2 or N+1... to adjust negative contrast

With roll film you may have different scenes shot in the roll, so you do a development that's good in general but it is not the optimal one for any particular frame.

LF fotographers, in general, take very seriously how the meter and develop each particular sheet. Roll film photographers can use the same techniques if all scenes in the roll have the same development needs, but they do that less, tending to use an standard development.


3D look:

Human vision perceives volumes mostly in 3 ways. One is stereoscopy, brain compares 2 different images, this works in a certain range. Another is perspective and comparing sizes of known objects. And another way brain preceives volume is with shading.

So the way you render the shades of a volume will lure more or less our brain for volume interpretation.

Then we also have OOF, out of focus areas, the way focus is lost before or after focus plane it also lures our brain, as when we explore something close we defocus what's not at the same distance we are looking.

Depth and 3D sensation is something an LF photographer may seek, as part of fine printing excellence.

IMHO 3D depiction is something often seen with LF photographers simply because they have a devoted effort on it, and also having easy camera movements to play with it.

Regards

Pere Casals
7-Nov-2017, 06:29
The problem with overexposure is that it increases graininess...

I'd add that for each film we have a "grain size" curve depending on density, so as we under or overexpose each zone shifts to another density in the negative, having a higher or lower density than before, and a new corresponding grain. Of course this has way less impact in LF...

This is tx vs hp5 comparison

https://www.flickr.com/photos/125592977@N05/28286548926/in/dateposted-public/

mdarnton
7-Nov-2017, 07:27
Pere, your pictures mirror my experience: more grain with underexposed Tri-X than over. Since taking a workshop with David Vestal in the 70s I have, as he recommends in his books, overexposed Tri-X to gain more shadow detail, and no extra grain resulted from this; in fact, it looks better to me, consistently, in every way.

Pere Casals
7-Nov-2017, 08:09
Pere, your pictures mirror my experience: more grain with underexposed Tri-X than over. Since taking a workshop with David Vestal in the 70s I have, as he recommends in his books, overexposed Tri-X to gain more shadow detail, and no extra grain resulted from this; in fact, it looks better to me, consistently, in every way.

Michael, yes... this is grain structure footprint !

With TX/TXP as we overexpose we relegate big grain to the darkest shadows, but with HP5 it is the counter, as we overexpose the peak graniness in the graph goes to left, and mids look more grainy. HP% tend to show grainy washed skies, while TX tends to show dramatic grain in dark clouds. (speaking about smaller formats...)

Anyway it is clear that grain perception not only depends on film and density, but also in local microcontrast, grain structure is shown well in washed areas, but it is masked by contrasty detail...


I love grain... one thing I lack in LF (I'm a newcomer in LF...) is grain expression.

A resource I like is how grain is increasingly perceived in OOF areas in portraits. Now that I'm making DIY emulsion I'm thinking in cooking mellon sized grains :) to experiment.

xkaes
7-Nov-2017, 08:53
I love grain... one thing I lack in LF (I'm a newcomer in LF...) is grain expression.

I love grain, as well -- for certain subjects and situations. In LF, it is often considered a dirty word, and smaller formats are discarded as "mere toys". I often use Kodak Royal-X and Infrared in 4x5" in order to maximize the grain. In smaller formats, I sometimes use Kodak 2475, 2485, and IR for the same reason -- even in my 17.5mm Toko and 16mm Minolta "toy" cameras. And my half-frame Olympus Pen FT cameras are great because I can maximize grain AND use all of my SLR lenses!

But I love grain-less prints too -- much of the time. It all depends on the subject and my mood.

Pere Casals
7-Nov-2017, 09:06
But I love grain-less prints too -- much of the time. It all depends on the subject and my mood.

Of course...

It would be great if D3200 was sold in sheets...