Why Medium Format?

[ErikKaffehr]

Hi Wayne,

Thanks for good info.

Regarding the original posting, I don't think we can draw generic conclusions regarding the bokeh thing. We need to look at individual lenses. There are some lens designs optimised for pleasant bokeh.

The older large aperture lenses were not very sharp fully open. That has changed with some of the new designs. Many lenses, including MF-lenses, need to be stopped down a bit to eliminate axial chroma that shows up as magenta/green fringing in OOF areas. I don't have the slightest idea about lenses for technical cameras, but very few large aperture lenses are fully corrected for axial chroma. Zeiss superachromats and Apo-lenses, the three Otuses, Zeiss APO Sonnar 135/2, some of the Voigtlander APO Lantars.

Regarding my Hasselblad V-series lenses, they all have axial chroma and it is not fully corrected at f/8, but apart from that they are decently sharp at full aperture.

Best regards
Erik

so as a retired portrait photographer, I would only add that I would never use either of those two focal lengths for shooting most portraits, especially more intimate individual studies.  Probably minimum 100mm on the 35 format sensor, and 150 mm on the 645 format sensor will give me better facial perspective, and dropping the background out of focus at something like f/5.6 so I have a little DOF for the face and I won't get some size distortion on facial features.

[voidshatter]

so as a retired portrait photographer, I would only add that I would never use either of those two focal lengths for shooting most portraits, especially more intimate individual studies.  Probably minimum 100mm on the 35 format sensor, and 150 mm on the 645 format sensor will give me better facial perspective, and dropping the background out of focus at something like f/5.6 so I have a little DOF for the face and I won't get some size distortion on facial features.

Hi, a Nikon 105mm f1.4 is equivalent as 163mm f2.2 in the 645 format. I don't think there's a lens in the 645 format near that angle of view with a stronger degree of background blur.

It's interesting to know that the western people prefer longer focal lengths to avoid perspective distortion of faces. In Asian, girls would pretty much prefer an angle of view of 28-35mm in 35mm format shooting downwards to make their faces look thin (slim), taking advantages of the perspective distortion from wide angles, because anything longer than 50mm in 35mm format may make their faces look fat.

[Phil Indeblanc]

To add to the OP question,

I think subject with very high detail and need of macro is another area where a MFD makes good sense. Maybe the A7r2 does as well, but for DOF and workflow and processing in C1 a MF makes better sense. Only thing is that you certainly don't need 100mpix to get "the job" done(of course there maybe even further exceptions in usage needs). I think the fine arts and "specialty vision" needs fit this area of high MP DB more, along with deep pockets.
Any magazine work I did was more than adequate with 22mp MF, nice lens on a 4x5. Then its processing/production.

Something about CCD transition and color is special
Something about the sensor size/format to lens ratio that breathes differently is a little special
Some uses of leaf shutter maybe special
Something about how you force to view your subject methodically is special. The viewfinder.

So to help with OP, I would get a used older setup to at least see the possible from a private seller. Or rent one for a shoot you have in mind.
Then use your 35mm setup to do the same shoot, or along side. See what you like, and your way of working and pace.
Then if you like and can afford a new system, and are willing to pay for such a system, give the local dealer a call.

But there is very little NEED. The need portion is your vision. 
A $40 Quartz Japanese movement tells the same time, if not more accurately than a $30K-500K tourbillon Swiss movement. But how it does it is very different. Not better or worse, but different. And in some needs, one of the differing options is preferred.

[Theodoros]

Pretty much a pro approach....

However Phil, that part with "artists and high resolution and deep pockets"... most of it I know, at least the serious stuff is LF film... (and then many times more than one sheet of film involved)... do you know different? ...I know some that are using MFDB, but not the most important ones, nor they do captures in the way people think of them in forum discussions...

[Phil Indeblanc]

You're right most, not all, use film.
One of them, who taught me a lot early on with 8x10/4x5, Per Volquartz used film.
Neil Snape(member) and mentor, who also taught me a lot, and encouraged me over 10 years back used film, and now is exclusively digital.
Others also, just not at the tip of my mind.

[jamgolf]

Artists hardly use digital backs

Seems acceptance of digital varies significantly among highly respected artists... Sugimoto rejects it, Struth employs digital only for post processing, Misrach & Burtynsky use it extensively.

Misrach:  http://spot.hcponline.org/pages/richard_misrach_with_peter_brown_488.asp
“...I had to consider alternatives to the 8x10. I started testing a medium format camera with a digital back. And that was that. I haven't shot film in 3 years (I've been accused of going over to the dark side!).”

Burtynsky:  http://aphotoeditor.com/2011/11/30/edward-burtynsky-interview/
“EB: They are now shot digitally.

JB: They are…

EB: Yes. I’ve tried every way I can, and film isn’t capable of that quality in aerial work. ”

Burtynsky:  http://v-e-n-u-e.com/Primary-Landscapes-An-Interview-with-Edward-Burtynsky
“It would be almost impossible with film to splice those images together so well and not have it look weirdly distorted or problematic. With Photoshop, and with digital files, you’ve got contrast control, the removal of haze, color filtration, and all of that, so I’m able to do things that, again, were not even conceivable five years ago.”

Gursky:  http://www.bbc.com/culture/story/20151106-andreas-gursky-the-bigger-the-better
“He also began to employ digital manipulation, first sparingly, then wildly. Gursky embraced digital manipulation early”

Struth   http://www.huffingtonpost.com/elena-cue/interview-with-thomas-str_b_7869912.html
“Well, I do use minimally invasive digital corrections, but I’m not inventing anything. The digital process allows me to deal with partial contrast and colour changes or adjustments in a much more finely tuned way than in the darkroom. The more recent pictures are mainly photographs taken with large format and sheet film, scanned into a file and then we work from the file.”

Sugimoto:  http://www.domusweb.it/en/art/2015/03/20/hiroshi_sugimoto_stop_time.html
“with the arrival of digital photography, you can make all the changes you wish, just as in painting. But I am not interested in this development. My photography, the traditional one, has existed for 180 years and I see myself as the last genuine photographer. I am very happy to have worked at the end of what we can call the true photographic era.”

[BernardLanguillier]

Seems acceptance of digital varies significantly among highly respected artists...

For some reason you forgot me on your list... I use digital.

Cheers,
Bernard

[jamgolf]

For some reason you forgot me on your list... I use digital.

Cheers,
Bernard

My apologies. Grossly negligent indeed.

[BJL]

Bart, your comments about DOF vs diffraction and shutter speed confuse me.

Firstly, to get equal FOV and DOF in a smaller format, one adjusts both focal length and aperture ratio in proportion to (linear) format size, which is to say keeping equal effective aperture diameter. That gives circles of confusion smaller in the same proportion as the image formed by the lens is smaller, so equally large on prints (or any other display medium) that have the image appearing equally large. From the examples given, this seems possible in 35mm format in comparison to most if not all MF lenses.

Secondly, the lower aperture ratio used in the smaller format to get equal DOF also gives equal diffraction effects on equal sized prints: like he circles of confusion, the diffraction spot sizes are also smaller in proportion to the size of the image formed at the focal plane, so come out the same size on same-sized prints.

Thirdly, as to shutter speed: this could be kept the same if the ISO speed can be reduced enough (in proportion to image area) which would also lead to roughly equal photon counts and do equal S/N ratio as far as photon shot noise goes. In cases where the ISO speed cannot be reduced enough, the consequence is only that the smaller format might have to use a higher shutter speed, which is usually not a problem. In the rare cases that this higher shutter speed is undesirable, an ND filter can be used – however that would leave the larger format with the advantage of higher photon counts and so potentially better IQ through higher S/N ratios and such.

I can see that lenses could sometimes give an IQ advantage to the larger format, due to factors like getting the desired DOF at a higher aperture ratio, where aberrations can be better controlled, but I do not know how such comparisons work out in practice.

[Wayne Fox]

Hi, a Nikon 105mm f1.4 is equivalent as 163mm f2.2 in the 645 format. I don't think there's a lens in the 645 format near that angle of view with a stronger degree of background blur.

It's interesting to know that the western people prefer longer focal lengths to avoid perspective distortion of faces. In Asian, girls would pretty much prefer an angle of view of 28-35mm in 35mm format shooting downwards to make their faces look thin (slim), taking advantages of the perspective distortion from wide angles, because anything longer than 50mm in 35mm format may make their faces look fat.

Personally I would rarely shoot a portrait at f/1.4 even it was available ... while it might do wonders with the background I think the DOF would be too narrow on the face, and most of the face would be soft. Yes for some occasional effect that might be nice.

Interesting perspective about the difference in Japanese and western portraiture, thx for that ...

[eronald]

Hi, a Nikon 105mm f1.4 is equivalent as 163mm f2.2 in the 645 format. I don't think there's a lens in the 645 format near that angle of view with a stronger degree of background blur.

It's interesting to know that the western people prefer longer focal lengths to avoid perspective distortion of faces. In Asian, girls would pretty much prefer an angle of view of 28-35mm in 35mm format shooting downwards to make their faces look thin (slim), taking advantages of the perspective distortion from wide angles, because anything longer than 50mm in 35mm format may make their faces look fat.

Of course there are exceptions to confirm the rule -  I think my antique Canon 200/1.8 is an old korean "marriage photo" lens.

Anyway, here is an interesting focal length study/animation:
http://petapixel.com/2016/07/28/camera-adds-10-pounds/

Edmund

[ErikKaffehr]

Hi,

One obvious advantage of medium format is high resolution. Now, present day medium format covers ground from the Leica S (37.5 MP) to 100 MP, with the cropped sensor 50 MP Sony sensor in the middle.

Some posters find 37.5 MP good enough for all purposes, personally I much doubt that, much because 37.5 MP is not enough to significantly suppress aliasing at medium apertures.

One application where high MP count is beneficial is printing large. That said, I looked into this a bit, and it was a sobering experience: http://forum.luminous-landscape.com/index.php?topic=111892.msg925446#msg925446

In short, I by and large fail to see advantages of high MP in decent size prints:

• Cannot observe difference between 24 MP and 39 MP in A2-size (16"x23") prints without a loupe.
• Can observe difference between 39MP and 85MP at A0-size (31"x47") at close view (around 50 cm) but not really at 80 cm.
  

Smaller pixels and high resolution may be helpful in reducing aliasing artefacts, see the attached screen dump. The image at the bottom, shot on the Pentax 645Z has a lot of aliasing on the green label, while IQ3-100MP image has absolutely clean rendition. In this case, I would think that the sensor ouresolves the subject than resolution being limited by lens.

Would be nice if some folks doing large size printing would elaborate on this.

Best regards
Erik

[ynp]

It's interesting to know that the western people prefer longer focal lengths to avoid perspective distortion of faces. In Asian, girls would pretty much prefer an angle of view of 28-35mm in 35mm format shooting downwards to make their faces look thin (slim), taking advantages of the perspective distortion from wide angles, because anything longer than 50mm in 35mm format may make their faces look fat.

Very interesting!

Thank you for your post. It explained a few things I noticed in the Asian Social media but was unable to understand.   Now it makes sense.


Sent from my iPad using Tapatalk

[kers]

...
Anyway, here is an interesting focal length study/animation:
http://petapixel.com/2016/07/28/camera-adds-10-pounds/

Edmund

Very nice indeed

[Theodoros]

Seems acceptance of digital varies significantly among highly respected artists... Sugimoto rejects it, Struth employs digital only for post processing, Misrach & Burtynsky use it extensively.

That's a good discussion.

Most artists use film for capturing, most artists use digital for post processing, what would be interesting to know, is if the ones that use digital for capturing use it in a way that has any relevance with the way enthousiasts with money to spend use their high resolution digital capturing devices...

I mean do they just put their camera on a tripod and then say: "Hey, that's a nice looking scene, I'll capture this..." or do they visualize a print, then design the process as to achieve the print visualized with all the elements included in the design (lighting, DR, detail, above all the looks), then decide on the right use of tools that will satisfy the process and then go to execute it by shooting some ...200GB of files out of which they choose the elements as to include in the final print of  3-4GB of size...
Also... is the print the result out of using one lens only for the whole process?
Are the elements used all with the same settings on the camera? same exposure, same DOF, same focusing, same tilts, same swings, same shifts? 

I only brought up the subject because there are members that insist on the importance of using (ultra) high resolution backs, while many pros on the other hand (like Phil mentioned above) are still happy with their ...22mp backs and are providing awesome results of the highest possible detail for many years now, without "upgrading" (perhaps because it would be a "DOWNgrading"?) ever crossing their minds...

I'm sure that there are members here, that would be happy as to ADVISE Misrach, or Burtynsky, or Gursky, or Struth  or Sugimoto or even other kinds than artists out the of working pros, ...on what they should be doing as to do it right!

[Bart_van_der_Wolf]

You're right most, not all, use film.

Hi Phil,

The more interesting question then becomes, Why?

Is is out of habit, do they see something in Film that they cannot do without to express their creative intent, is it just lack of skill in digital, or ... ?

Otherwise, it all reminds me a bit too much of those who worship Black and White photography, because their early encounters with photographic work was from photographers who shot in Black and White (because there was hardly any color available). But then Ansel Adams didn't have the same color material choices that we do, and he probably would have loved digital photography for its ability to additionally control lighting in Postprocessing, but it simply wasn't around yet.

Cheers,
Bart

[GrahamBy]

The more interesting question then becomes, Why?

Indeed. Another possibility is that it is a form of discipline, which imposes a certain way of working... rather like writing poetry in a specific meter.
I don't think the lack of skill argument flies, since by scanning the film they have in any case to jump most of the technical hurdles of digital.

Otherwise, it all reminds me a bit too much of those who worship Black and White photography, because their early encounters with photographic work was from photographers who shot in Black and White

I don't know that I worship B&W... I simply prefer it. It's a different medium, just as charcoal drawing is different to watercolour is different to oils. Or from photography. There is a greater element of abstraction, usually. Doubtless others see it differently and some may indeed have an ideological vision.

[Theodoros]

Hi Phil,

The more interesting question then becomes, Why?

Is is out of habit, do they see something in Film that they cannot do without to express their creative intent, is it just lack of skill in digital, or ... ?

That's the easy part to answer... because they prefer the "looks"? Because the find the looks of film more communicative? ...Just like vinyl sounds out of a good triode tube single ended stereo with material also recorded in analog?

Communication result out of the product is the first thing an artist (of any kind of art) is after....

Otherwise, it all reminds me a bit too much of those who worship Black and White photography, because their early encounters with photographic work was from photographers who shot in Black and White (because there was hardly any color available). But then Ansel Adams didn't have the same color material choices that we do, and he probably would have loved digital photography for its ability to additionally control lighting in Post processing, but it simply wasn't around yet.

Cheers,
Bart

I'm afraid there is no such thing as "black and white photography"... In a composition (any composition out of any art) the elements that are destructive as to make the subject more communicative must be removed... other wise they distract attention from being concentrated to the subject itself... Bob Dylan and Neil Young where superb in this... They could have in the same an album a composition with only a harmonica and a guitar used and then, in the very next song use an orchestra with some ...70 instruments involved!! It's all a matter on how a composition works best... If the destructive element is color, then it must be removed... if the destructive element is a particular color (or colors) then it must be removed or replaced with one it works...

[jamgolf]

I mean do they just put their camera on a tripod and then say: "Hey, that's a nice looking scene, I'll capture this..." or do they visualize a print, then design the process as to achieve the print visualized with all the elements included ...

Obviously artists at that level have individual artistic visions and thought process & methods to achieve their vision. Since most here are not personal acquaintances of such respected artists (at least I'm not) the only way to understand their work and methods is to study their work,  read their books and read/watch interviews where their thought process and work is discussed.

Richard Avedon's "In the American West" shows what it took to create that body of work. Victoria Sambunaris's "Taxonomy of a Landscape" and accompanying contact sheets show behind the scenes and a glimpse of the effort. Video interviews with Struth are very revealing of his way of conceiving and his thought process etc. etc.

Everyone starts at "Hey, that's a nice looking scene, I'll capture this..." but then the process of evolving as a practitioner begins.
How far we get depends on talent, work ethic, desire, vision, passion, commitment and did I mention talent

[Bart_van_der_Wolf]

Bart, your comments about DOF vs diffraction and shutter speed confuse me.

Hi, it was not my intention. Maybe it's due to the confusing responses that denied the generally shallower DOF of MF, unless one starts to change apertures to (over-)compensate. Apertures change DOF, which should be no surprise.

Firstly, to get equal FOV and DOF in a smaller format, one adjusts both focal length and aperture ratio in proportion to (linear) format size, which is to say keeping equal effective aperture diameter. That gives circles of confusion smaller in the same proportion as the image formed by the lens is smaller, so equally large on prints (or any other display medium) that have the image appearing equally large. From the examples given, this seems possible in 35mm format in comparison to most if not all MF lenses.

Yes, it it possible to compensate for the differences in DOF that are caused by the different focal lengths needed to adjust the FOV. No disagreement on that, as far as I'm concerned.

But one will have to adjust the Aperture to achieve that, and that also requires a change in exposure time to compensate. There may be constraints (e.g. too long an exposure time to avoid a certain level of motion blur on the MF gear).

Secondly, the lower aperture ratio used in the smaller format to get equal DOF also gives equal diffraction effects on equal sized prints: like he circles of confusion, the diffraction spot sizes are also smaller in proportion to the size of the image formed at the focal plane, so come out the same size on same-sized prints.

The aperture number (which determines the angular aperture or Numerical Aperture) determines the diameter of the Airy Diffraction pattern. So regardless of the focal length, the same f-number will produce the same amount of diffraction on the sensor plane. With the required (usually) smaller output magnification of MF, the diffaction in output will be less. Obviously, if we had compensated the DOF with changed apertures, things like diffraction would also be equal. One exception, if the required narrower aperture number for the MF exceeds the diffraction cut-off frequency of the sensor, there will be a total loss of resolution, while there might still be some marginal resolution on the wider aperture for the smaller format.

Thirdly, as to shutter speed: this could be kept the same if the ISO speed can be reduced enough (in proportion to image area) which would also lead to roughly equal photon counts and do equal S/N ratio as far as photon shot noise goes.

A lot can happen when ISO is changed (depends on the sensor technology and supporting electronics), but it doesn't change the number of photons that a given aperture number allows to pass (per unit time). The physically larger aperture of the longer MF focal length lets in more photons, but they are spread over a larger sensor area, so total exposure per pixel remains the same, until we change the aperture numbers between formats to compensate for DOF differences. Changing aperture numbers will also need to be compensated for by adjusting exposure time or flash intensity, because different numbers of photons will be let in. ISO does not change that.

In cases where the ISO speed cannot be reduced enough, the consequence is only that the smaller format might have to use a higher shutter speed, which is usually not a problem.

Or the larger format has to use a slower shutter speed, which might get to be an issue at large magnifications (although MF usually requires less output magnification).

In the rare cases that this higher shutter speed is undesirable, an ND filter can be used – however that would leave the larger format with the advantage of higher photon counts and so potentially better IQ through higher S/N ratios and such.

Higher photon counts, but also spread over a larger surface! Local exposure of larger magnified detail is where the S/N ratio counts, and where MF has opportunities (in addition to higher MTF due to lower spatial frequencies of the more magnified projected scene), especially in postprocessing it will give more quality to work on. Unfortunately aliasing artifacts may prevent exploiting some of the advantages.

Cheers,
Bart