Is a cropped MF/LF identical to 35mm?

tomfrh · Mar 6, 2016

people often say that larger negatives give better image, and that this goes beyond mere resolution. People say tones are smoother etc.

I've noticed that in my negs.

What I've never done though is compare a 35mm with a cropped larger format. Eg 35mm at 100mm, compared with 6x7 at 100mm, and cropped to 35mm format.

I'm assuming it will be the same, assuming the same film and lens?

BetterSense · Mar 6, 2016

It is not clear to me what you are asking.

Thomas Bertilsson · Mar 6, 2016

It will not be the same. 35mm lenses will show better resolution than the cropped 24x36mm frame from a 6x7 negative.

But then again, in the grand scheme of things it probably won't matter much.

tomfrh said:
people often say that larger negatives give better image, and that this goes beyond mere resolution. People say tones are smoother etc.

I've noticed that in my negs.

What I've never done though is compare a 35mm with a cropped larger format. Eg 35mm at 100mm, compared with 6x7 at 100mm, and cropped to 35mm format.

I'm assuming it will be the same, assuming the same film and lens?

John Koehrer · Mar 6, 2016

Crop as you wish but I don't believe that would change the differences in tonality. Would it be the same as
enlarging the same scene to the same physical dimensions? IE: subject measures ?" in both prints?

tomfrh · Mar 6, 2016

Why will a 35mm look better than a crop from a 6x7?

Poisson Du Jour · Mar 6, 2016

If it's a question about size, no. A MF negative e.g. a 6x7 negative/transparency, is 400% larger than 35mm. A crop from a 6x7 to the 35mm dimensions will only show a much larger section of the image at a correspondingly lower magnification, but that cannot in any way be interpreted as meaning that medium format is inferior in terms of resolution to 35mm. It's not. The smaller format limits resolution the higher the enlargement, while medium format will not lose out until very, very large prints are made (80x70cm is the highest I've gone with MF, limited by printer output, and still tack sharp, compared to the maximum I'm happy to print to from 35mm being 60x50cm).

In regards to tonality, 35mm squeezes in a lot of contrast/tone into a very small space. In MF and LF, those same things are spread over a much larger area. This means less guesswork with metering and a more predictable outcome (if the photographer has the required skills to meter a scene in a methodical, balanced way).

Dr Croubie · Mar 6, 2016

I think I can figure out the question, so here are my answers:
MF and LF lenses are the same as 35mm lenses in terms of focal length. 100mm is 100mm is 100mm.
35mm film grain is the same as MF film grain is the same as LF film grain (with a few exceptions like Tri-X and different bases).

Thus, pretend you take a photo with a 100mm lens at f/8 on a 35mm camera, take a photo with a 100mm lens at f/8 on MF, ie 645, 6x6, 6x7, 6x9, 617, take a photo with a 100mm lens at f/8 on 4x5, take a photo with a 100mm lens at f/8 on 8x10.
Process them identically, cut out a section of film 24x36mm from each of those, enlarge them, and all things being equal they will look identical. Grain the same size, same field-of-view, same tonality because there's the same number of grains in the same area.

But all things are not equal. 35mm film is usually enlarged what, 5-10-20x (20x is 18x28")? And MF film what, 3-10x?
It's hard enough trying to find an 8x10" enlarger, can you imagine (or calculate) how big a 20x enlargement from an 8x10 would be? Most these days would be contact-printed (it's all I can do with my 8x10s), I can't imagine regularly enlarging any of them above 2-3x (3x is 24x30", that's huge).
Thus, there's no point in making LF lenses that can resolve as well as 35mm lenses. It's possible, but they would be astronomically expensive and not worth it for 99.5% of LF shooters.
Sharper smaller lenses taking negs that could be enlarged were the whole point of 35mm cameras when Barnack invented them.

Also, not all 35mm lenses are sharper than MF lenses or LF lenses, but there's definitely a trend.

So in a way, yes they will look the same. It's possible that a very sharp 35mm lens will look better than a dog MF lens. And vice-versa.
But in a scientific, theoretical, non-reality sense, get two lenses with the exact same resolving power and yes, they'll look identical.

tomfrh · Mar 6, 2016

Poisson Du Jour said:
In regards to tonality, 35mm squeezes in a lot of contrast/tone into a very small space.

To clarify, I'm referring to the same focal length (and same aperture/position/etc), ie same film area for a given subject.

Eg Capture an oak tree with 100mm lens on 35mm and on MF, all else being equal. Same aperture. Same subject distance.

Does the oak tree look better on either format, or the same?

bdial · Mar 6, 2016

The size of the image is the same for a given focal length lens regardless of format.
The differences will be down to elements affecting sharpness and resolution and that could go either way.

Somewhere I have some 6x6 and 4x5 negs of the same subject, both made with (different) 150mm lenses and prints made from each are very hard to tell apart (cropped in the case of the 4x5).

tomfrh · Mar 6, 2016

Dr Croubie said:
But in a scientific, theoretical, non-reality sense, get two lenses with the exact same resolving power and yes, they'll look identical.

bdial said:
Somewhere I have some 6x6 and 4x5 negs of the same subject, both made with (different) 150mm lenses and prints made from each are very hard to tell apart (cropped in the case of the 4x5).

Thanks guys, this answers my question!

chuck94022 · Mar 6, 2016

tomfrh said:
To clarify, I'm referring to the same focal length (and same aperture/position/etc), ie same film area for a given subject.

Eg Capture an oak tree with 100mm lens on 35mm and on MF, all else being equal. Same aperture. Same subject distance.

Does the oak tree look better on either format, or the same?

One of the reasons it remains an apples to oranges question, even if the focal length and aperture are the same, is that the image circles on the film are different. The 35mm lens is designed to project an image circle not much larger than the diagonal of the 35mm film area. Some are right on the edge, and with certain apertures, you'll see vignetting at certain apertures.

A 100mm lens for medium format will project a substantially larger image circle onto the film. But lest you think this means you'll get the same angle of view (same "zoom") as a 35mm, you won't. On medium format, a 100mm lens seems like a "wider" lens. But that said, you get the same qualities as the 35mm lens in terms of image distortion - a good quality 80mm lens on medium format, while giving a "normal" angle of view, is still a good portrait lens. You can just get a bit closer because you have a wider angle of view on the film than with 35mm.

When you move up to large format, the lenses get less and less complicated. Does that make the image quality better? I have no idea, someone who is an expert should weigh in. I don't know the qualitative impact of a larger image circle, but an expert can probably talk about the tradeoffs of image circle and the multiple layers of glass required to deliver a sharp result on 35mm vs, for example, 4x5.

Sirius Glass · Mar 6, 2016

To add to the reason that the answer is not simple is that a 100mm 35mm lens, a 100mm MF lens and a 100mm LF lens could well be different lens designs with different number of lens, different grouping, different coatings, ... each with its own set of aberrations, own set of MTF curves, different distortions.

Luckless · Mar 6, 2016

chuck94022 said:
One of the reasons it remains an apples to oranges question, even if the focal length and aperture are the same, is that the image circles on the film are different. The 35mm lens is designed to project an image circle not much larger than the diagonal of the 35mm film area. Some are right on the edge, and with certain apertures, you'll see vignetting at certain apertures.

A 100mm lens for medium format will project a substantially larger image circle onto the film. But lest you think this means you'll get the same angle of view (same "zoom") as a 35mm, you won't. On medium format, a 100mm lens seems like a "wider" lens. But that said, you get the same qualities as the 35mm lens in terms of image distortion - a good quality 80mm lens on medium format, while giving a "normal" angle of view, is still a good portrait lens. You can just get a bit closer because you have a wider angle of view on the film than with 35mm.

When you move up to large format, the lenses get less and less complicated. Does that make the image quality better? I have no idea, someone who is an expert should weigh in. I don't know the qualitative impact of a larger image circle, but an expert can probably talk about the tradeoffs of image circle and the multiple layers of glass required to deliver a sharp result on 35mm vs, for example, 4x5.

It is a wider overall field of view, but at the same distance to the subject a 100mm lens on a 35mm camera will project the scene onto the smaller film the same as it the 100mm medium format will project an image onto the same sized area of the film. It is like looking out a large bank of windows. If most of them are shuttered then you have a narrow field of view, but if you open more of them and look out from the same spot you 'see more', but the part that you could see through the first window hasn't changed.

How different the image looks if you take it on 35mm film or cut the same sized section out of the centre of a medium format film then comes down to lens design specifics. (Which may include various distortions and aberrations, vignetting differences, etc.)

MattKing · Mar 6, 2016

Cameras and lenses are designed together as systems. And design decisions are inherently compromises.

A medium format or larger camera will have to be able to give quality results out to the corners of a much larger piece of film than a 35mm camera. The compromises inherent in that larger design are likely to differ from the compromises inherent in the smaller design.

On the other hand, competitive forces may force designers to make other compromises with 35mm lenses. In particular, customers may demand larger maximum apertures and fast autofocus with 35 m, when the demand for same in medium format is less.

So the answer to the question is: probably not identical.

Ko.Fe. · Mar 6, 2016

I crop 6x9 to 6x6 and 6x6 to 8x10. Looks fine.
I would not crop MF to 135 negative size.
If OP exersize something theoretical here about equal focal length and such... Here is difference in 135, MF and LF.
Doesn't matter if someone will try to match whanether. It is always different.

tomfrh · Mar 6, 2016

Luckless said:
at will project an image onto the same sized area of the film. It is like looking out a larg

Yes this is fundamental to my question. The image is the same size.

I was asking whether the little 35mm "window" in the MF is meaningful distinguishable from a 35mm frame, all else being equal.

Perhaps 120 or sheet film works a bit differently. Perhaps the different camera sizes have an impact...etc

It sounds like the answer is no.

ambaker · Mar 6, 2016

I have a 35mm back for my Mamiya 645. So it does essentially what the OP is asking. It places the 35 mm film in the center of the 6x4.5 frame. The back contains a mask to create a standard 35mm image. The sharpness is good. I haven't tested it next to a 35mm camera with a comparable lens. I would expect that the 35mm camera to be a bit sharper. But I can say that the difference is not immediately obvious. At least to my eyes. Sounds like an interesting project though that I may have to undertake. However, if I wind up hating the Mamiya results when done side by side, I am holding you all personally responsible.

Thomas Bertilsson · Mar 6, 2016

tomfrh said:
Why will a 35mm look better than a crop from a 6x7?

There was an actual scientific test comparing 35mm to 6x6 and 4x5, where they measured actual resolution and what the different formats could muster.

In the case of Tri-X the film was the limitation of the system, but in the case of TMax 100 the limitation started to become the lenses.
We had a 50mm Zeiss compared to an 80mm Zeiss on a Hasselblad, and I believe a 150 Schneider Symmar for 4x5.
Using the TMax 100 film, the MF and LF lenses started to lag behind in resolution, and the differences between the formats started to become less apparent. I can't find a copy of it right this minute, but it was based on facts, and not some opinion of what 'might' be better, and it was a test concerning resolution only.

So, yes, a 35mm frame shot in a 35mm camera with a quality lens will probably give you a better enlargement than a cropped medium format neg to the same size. As long as the film used will allow the 35mm system to show its inherent advantage in resolution.

Chan Tran · Mar 6, 2016

tomfrh said:
Why will a 35mm look better than a crop from a 6x7?

Because assuming the film stock are the same cutting out a 24x36mm portion from a larger film is exactly like the 35mm frame. The different is the lens. Lenses designed for 35mm format only have to cover a much smaller area but the do has higher resolution that is the lines per milimeter resolution is better than lenses for larger format.

ic-racer · Mar 6, 2016

tomfrh said:
people often say that larger negatives give better image, and that this goes beyond mere resolution. People say tones are smoother etc.

I've noticed that in my negs.

What I've never done though is compare a 35mm with a cropped larger format. Eg 35mm at 100mm, compared with 6x7 at 100mm, and cropped to 35mm format.

I'm assuming it will be the same, assuming the same film and lens?

Make sure the unprinted area of the 6x7 negative is masked off when enlarging, otherwise it may have less contrast than the 35mm enlargement.

markbarendt · Mar 6, 2016

Thomas Bertilsson said:
It will not be the same. 35mm lenses will show better resolution than the cropped 24x36mm frame from a 6x7 negative.

But then again, in the grand scheme of things it probably won't matter much.

Yes, this is right.

RalphLambrecht · Mar 7, 2016

tomfrh said:
people often say that larger negatives give better image, and that this goes beyond mere resolution. People say tones are smoother etc.

I've noticed that in my negs.

What I've never done though is compare a 35mm with a cropped larger format. Eg 35mm at 100mm, compared with 6x7 at 100mm, and cropped to 35mm format.

I'm assuming it will be the same, assuming the same film and lens?

It will be the same

bluez · Mar 7, 2016

I have a very sharp mamiya 150mm 2.8 A lens, that i uses on both my mamiya 645 pro and Canon 35mm eos 1V (with adapter). a 6x4.5 cropped down to 35 mm size will look exactly the same (same film type). Should i use a another lens from mamiya like the 210 mm (not as sharp as the 150mm) against my Canon 200mm 2.8 L the Canon will produce a sharper image than a cropped down image from the 645 Pro.

removed account4 · Mar 7, 2016

(there was a url link here which no longer exists):

i hope you do a test yourself and post your results to this thread !

have fun !
john

wiltw · Mar 7, 2016

RalphLambrecht said:
It will be the same

I agree.

One must consider first equalizing as many parameters as you can...

if you mount a 100mm lens on 135 format body, an object 5' tall which is 21' away will fill the short dimension of the frame...it is 24mm tall at the focal plane.
So putting a 100mm lens on 645 will result in the same object still being 24mm tall of the 42-43mm frame height.
And putting a 100mm lens on 4x5" view camera will result in the same object still being 24mm tall of the 93mm frame height.

Using the same emulsion on all three cameras, and masking the entire negative down to the same 24x36mm net size when enlarging will result in IDENTICAL tonality and gradations of tone in all three shots...the same subject occupies the same area of film on all three shots, so any 'advantage' of larger formats is lost.

In reality, the preceding paragraph's description is simplistic in the assumption that the same 100mm lens with the same detail resolution in line-pairs per millimeter can cover the huge image circle of 4x5" as well as the tiny image circle of the 24x36mm frame! In reality, the lens made to cover the image circle of 4x5" has far lower per-square-millimeter detail resolution than the same FL made to cover only the 135 format frame.
So when using the 'same FL' but a lens designed appropriate to the format size, when we mask all three to the same net 24x36mm negative for enlargement, the 135 format neg will have far better detail resolution of the 5' tall subject than would be seen on the 24x36mm crop of the 4x5 neg.

Is a cropped MF/LF identical to 35mm?

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