• Welcome to Photrio!
    Registration is fast and free. Join today to unlock search, see fewer ads, and access all forum features.
    Click here to sign up

I just don't get the 35mm vs bigger format thing.

The four levels of competence in any discipline:

Level 4: I do know how much it is that I do know.

Level 3: I don't know how much it is that I do know.

Level 2: I do know how much it is that I don't know.

Level 1: I don't know how much it is that I don't know.



Ken
 
Last edited by a moderator:
It's really important to always try to get yourself up to at least that second level of competence. Remember the Clint Eastwood admonition?

"A man's got to know his own limitations..."

Ken
 

I grant you that LF requires a higher degree of perfectionism to get it right. The old adage is that you will see a bigger degree of improvement between 35mm and MF than you will between MF and LF.

Taking just the square area from each format 135 is 24x24 = 576mm², MF is 56x56 = 3136mm² which is 5.44 times bigger than 135 format. And 4x5 is approx 95x95 = 9025mm² which is 2.8 times bigger than MF but 15.6 times bigger than 135 format.

That extra 5.44X area jump from 135 to MF covers a lot of sins. The jump from MF to LF is only half the increase of 135 to MF So I suspect that you may not see much difference if you are at LF level 1. But you will see a large difference even if you are LF level 1 and have jumped straight from from 135 format to LF.
 
MattKing said:
Again, usually when you are shooting with a TLR above your head?
Click to expand...

˙˙˙ɐᴉlɐɹʇsn∀ uᴉ ʇᴉ ɥʇᴉʍ ƃuᴉʇooɥs ɯɐ I ssǝlu∩



Ken
 

The unknown unknowns are the ones that cause problems in engineering. They are referred to as unk-unks.
 

A narrower aperture is more limited in resolution (due to diffraction) than a wider aperture lens, that's true. But very rarely is a 35mm lens limited by diffraction alone. Most of them, (and this includes very expensive lenses), are limited by their own aberrations and mechanical tolerances. Tolerances do not scale with format; a very good large format lens can be built to the same tolerances than a good 35mm lens. And, as I posted before, a large format lens needs a smaller aperture to achieve the same DOF which makes life easier for lens designers: they can correct such lens further.

And, again, lens tests on the old Robert Monaghan's forum thoroughly dispel the myth that Medium Format and Large Format lenses are lacking in resolution. 35mm film might be enlarged 4X to be on par with a 4x5" negative, but the lens resolution increase with the 35mm lens is NOT 4X, not by any chance. Chances are the resolution of the 35mm lens, given a high quality large format lens, will be similar or at most 1.5X the resolution of the LF lens.

Simply put, lens resolution does not scale at the same rate than the area reduction of going to a smaller format.

Additionally, those considerations have "resolution" understood as "lines per mm" resolving power. However, the system includes the film area, and the bigger film area means bigger total resolution.

Compound this with the MTF curve argument I posted before: Simply put, the film's response (percent contrast) decays with increased resolution. Thus, even if you could record a scene with 35mm and 4x5" film, with a "magical" 35mm lens that is able to put exactly the same amount of detail over the whole frame of image, due to the MTF response of film, the larger format negative (4x5" in this case) will have a clearer, better defined rendering of such details.

The same, in a sense, happens with Digital SLRs, and that's why you can have a 24MP full frame 35mm DSLR which records less detail (less clarity) than a 24MP medium-format DSLR... even when using top lenses! That's why even Leica, who pride themselves in the quality of their 35mm lenses, had to go for a bigger-than-35mm-full-frame format on their latest DSLR -- because it's the only way they can outperform the competition in clearly-resolved resolution!
 
Last edited by a moderator:
Zeiss say that F5.6 is as good as it gets. Funny that because I quoted F5.6 on 135 format and with the right lens that WILL exceed the 200 lp/mm that Ektar is claimed to give also the 200 lp/mm that Fuji Acros claims to be capable of. The lens is capable of more than the film in the real world with the right conditions and handling. So I'm not sure what you're claiming unless its that you unwittingly know better than Zeiss or unwittingly by implication that Zeiss have got their numbers wrong.
 
RobC If there's one thing I've learned on this forum, it's that the laws of physics don't apply to film cameras. Which is why Zeiss and, let's face it, all of optical design theory is entirely wrong.

With this newfound knowledge, I've decided to get out of lens design and go into management...
 
Last edited by a moderator:

Well at F5.6 200 lp/mm is only approx 80% of theoretical limit and if the lens at F5.6 is only capable of 50% of theoretical limit then it would still give 140 lp/mm on film. Assuming 20/20 vision we would need at most 8 lp/mm in the print and more likely 5 lp/mm so that would allow approx 30X enlargement and still retain high quality. But perfection is the name of game when trying to achieve the absolutes from a film/camera/lens setup and any tiny mistakes will drop that down to much lower levels.
 
Nodda, you're allowing your training, logic and experience get in the way of having fun.
 
Hey ya'll... The undertaker is here.. Ya'll finished beating this poor dead horse?? He's ready to take it away and bury it...
 
leicarfcam said:
Hey ya'll... The undertaker is here.. Ya'll finished beating this poor dead horse?? He's ready to take it away and bury it...
Click to expand...

Perhaps the wisest move might be to gently invoke the mercy rule and quietly close this thread?

Jus' sayin'...

Ken
 
frank said:
Not a grave mistake.
Click to expand...

I'm the one who's been digging a grave for himself...

It seems absurd, and might be. But it had to be said.

---

You can quote me on it.

A Minox negative and an 8x10 negative produce the same amount of detail in a 20x24 silver gelatin enlargement.

Bill Burk

---
 
Refer to Ralph Lambrecht's chart showing diffraction limits and line pairs per millimeter... Post #2 of this thread.

Imagine the Minox 8mm x 10mm film image area at 200 line pairs per millimeter, which a little Google might turn up as reasonably attainable... It's up in the upper-left of this graph, and at f/3.5 (at least with my Minox C) which is below diffraction limit.

8x10 inch film is in the lower right corner, I imagine, diffraction limited around f/64

(there was a url link here which no longer exists)
 
leicarfcam said:
Hey ya'll... The undertaker is here.. Ya'll finished beating this poor dead horse?? He's ready to take it away and bury it...
Click to expand...

The ship sailed out of the train station on the west bound tracks ...


The train steamed out of the harbor and into the sunset ...
 

RobC,

I like where you are going with this... I was puzzling this out. Keep in mind 5 line pairs per millimeter is 10 lines per millimeter and so that is about 254 pixels per inch. We probably only need half of that to be satisfied when looking at the larger prints...
 
We'd need 3500 lines of information on the 24 inch side of the 20x24 inch paper, to give 150 lines per inch of detail on the print (allowing a half inch border).

175 line pairs per millimeter to get 3500 lines of information out of the 10 millimeter image dimension of a Minox negative.

And if the Minox and a real existing film can provide 200 line pairs per millimeter, we already have more than we need.
 
Now Ralph Lambrecht says 35mm film / Summicron, ambitiously can get 97 line pairs per millimeter. So maybe, unless the Minox really is different, maybe I am crossing a line here.
 
Someone please point out a fallacy in my thoughts. I expected this to be an exercise in the absurd, not a matter of accepted fact.

I think the 8x10 negatives themselves carry far more information than the Minox negatives, but it's not getting to paper and then to the viewer's eye.

This might be why such an absurd statement may carry a grain of truth.
 
You must log in or register to reply here.
Menu
Log in
Register