Dogman
Veteran
Before digital, arguments were based on large format vs medium format, Speed Graphic vs Rolleiflex, medium format vs 35mm, SLR vs RF, Leica vs Contax, Nikon vs Canon, AF vs manual focus, etc. Photographers seem to love the minutiae involved in every aspect of the pursuit. And we love to argue about it all. It sold photo magazine in the past and it keeps bloggers/vloggers in business today.
willie_901
Veteran
A combination of high sensor surface area and high lens element surface area represents a significant advantage. Maximizing the total signal level (sensor illuminance) while using longer shutter times and, or wider apertures is often an advantage. More signal also means less relative photon noise levels.
In principle, simply increase lens surface area can compensate for reduced sensor areas. In practice, this is impractical because with current optical technologies those lens would be very large and expensive.
I think we are about 5 years away from a new generation medium format digital sensors (larger than the current 44 x 33mm sensors) becoming the standard for the highest level of sensor performance and APS-C and m4/3 becoming the preferred platforms for people who value the advantages of smaller and lighter gear.
In principle, simply increase lens surface area can compensate for reduced sensor areas. In practice, this is impractical because with current optical technologies those lens would be very large and expensive.
I think we are about 5 years away from a new generation medium format digital sensors (larger than the current 44 x 33mm sensors) becoming the standard for the highest level of sensor performance and APS-C and m4/3 becoming the preferred platforms for people who value the advantages of smaller and lighter gear.
retinax
Well-known
No-one disputes that one can stop down. However Ming Thein talks about hand held photography, so the price to pay for stopping down beyond a certain point is higher ISO, as he points out. Which may still be better, or not.
For tripod photography your point stands. Even more, I doubt that diffraction actually doubles per f/stop down that is needed to get the same dof for FF compared to APS-C, because the length of the edge of the diaphragm (which is responsible for diffraction) doesn't change in a linear way with the size of the aperture. Or does it? Maybe because we need to consider the different aperture size needed for the different focal length to get the same fov. Ok I'm in over my head.
ptpdprinter
Veteran
At least you acknowledge the difference. A lot depends on print size.
michaelwj
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This was a seperate rant unrelated to Ming’s article...
It doesn’t exactly double, but it’s close enough (there’s a small angle approximation in there). Regarding the different linear changes when focal length changes, the f in f-stop is normalising for focal length. We need to un normalise it for depth of field. So, stopping down to f/8 on a full frame lens is the same linear aperture size as stopping down to f/4 on m43 for the same angle of view. Depth of field is related to the actual aperture size.
ptpdprinter
Veteran
As if any of this makes much difference in the real world. You never heard any of these concerns about comparative diffraction between FF and MF film shooters. Perhaps someone can post some images illustrating this problem.
retinax
Well-known
It certainly is of no practical concern for me, it's just interesting to think about. And could be useful when one gets to the extremes, w.r.t. diffraction that's probably macro photography. BTW I'm purely a film shooter at this time.
Rob-F
Likes Leicas
It all comes down to the same old truism: With a bigger fancier camera you might get a technically better photo; but whether it's a better picture depends on the photographer.
michaelwj
----------------
This was a seperate rant unrelated to Ming’s article...
It doesn’t exactly double, but it’s close enough (there’s a small angle approximation in there). Regarding the different linear changes when focal length changes, the f in f-stop is normalising for focal length. We need to un normalise it for depth of field. So, stopping down to f/8 on a full frame lens is the same linear aperture size as stopping down to f/4 on m43 for the same angle of view. Depth of field is related to the actual aperture size.
If I can try to express myself more clearly after a few coffees on a Saturday morning...
For a given field of view and depth of field (f/4 12mm m43; f/8 24mm FF) the airy disc covers the same % of the recording medium. If we have the same number of pixels then diffraction becomes visible at the same depth of field and angle of view regardless of the format. The argument that a smaller format allows for greater depth of field is false (except when you run out of stops at the largest f number, which is a lens problem, not a format problem)
Adding more pixels however allows you to sample the airy disc at a higher spatial frequency, and in the end looks better.
Dan
Let's Sway
thank you thank you thank you
Tim Murphy
Well-known
DING, DING, DING, We have a winner!
DING, DING, DING, We have a winner!
Dear Rob,
Trudat
Regards,
Tim Murphy
Harrisburg, PA
DING, DING, DING, We have a winner!
Dear Rob,
Trudat
Regards,
Tim Murphy
Harrisburg, PA
willie_901
Veteran
I don't have any images. But, the reason for less concern is because film shooters evaluated perceived image sharpness from prints while digital image sharpness is typically evaluated by viewing high-resolution monitors.
The system spatial resolution – MTF50 – depends on the lens, film resolution, development technique, enlarger optics and paper resolution. For small to medium sized prints, diffraction broadening could be less obvious going from small to large film surface areas. Before digital, film work that required large prints was usually done using large film formats. If 135 format film was printed to the same large size, and the negatives had a high system MTF50, diffraction broadening would be a concern.
Details
Digital imaging system spatial resolution (MTF50) is often superior than film because image comparisons are typically made by visual inspection using high MTF50 monitors.[1] Viewing prints alone, the system MTF50 will be lower and the diffraction broadening will become less obvious. Another difference from film involves pixel pitch. As pixel pitch increases the effective diffraction broadening deceases. Sensors with both large pixel pitches and large surface areas are susceptible to diffraction broadening.
For all images, when the airy disk diameter becomes larger than the circle of confusion (CoC), diffraction broadening becomes relevant.
Diffraction broadening is caused interference between light rays passing through an aperture. Circular apertures in 2D imaging produce a diffraction pattern – the airy disk. The airy disk primary peak diameter quantifies how much broadening occurs.
Diffraction depends on the film area because the CoC is a function of film area. For 135, 645 and 4X5 formats the CoCs are 0.029, 0.047 and 0.11 mm respectively.
The CoC depends the ratio of the viewing distance divided by the desired final-image resolution in lp/mm for a 25 cm viewing distance. This value is then divided by the enlargement factor (for a direct contact print the enlargement factor = 1). Larger media surface areas require less enlargement and this means the CoC is larger.
1. Neither film nor digital prints are have an inherent MTF50 advantage. The system MTF50s for film and digital prints both depend on more than just the sensors' and films' resolution limits.
emraphoto
Veteran
Indeed. All of these conversations rely on narrowing 'photograohy' down to a singular whereas the reality is, photography can be a lot of things. Similar to judgment of the end result, be it a physical print or online.
markbakovic
Member
You did but the language was usually different.
First bit of this might help:
http://spiff.rit.edu/classes/phys312/workshops/w10c/telescopes/telescopes.html
Fast lenses are less likely to achieve the diffraction limit. The theoretical resolution of a large format and kleinbild lens may be the same, but for the same field of view and manufacturing tolerances a longer lens is more likely to achieve that (or some % of that) performance.
Also: since f# determines resolution at the detector independent of focal length imaging a scene with a 50mm f.8 lens and a 150mm f.8 lens produce spots the same size (if they're both perfect). However, the aperture of one lens is ~6mm, while the other's is ~18mm, so each spot covers and area of the scene one third as big from the LF "normal" 150. If your grain/pixels are small enough to sample the spots correctly you get 3x the detail in the big format "at the same field of view". Another way of looking at it is you could stop down further and lose no detail in the scene, while making smaller spots on your detector (to take advantage of fine grain emulsion, say).
It might just be easier to think that at the same grain/pixel size, more of them across the frame translates to more of them across a given detail in the scene (think similar triangles with a given angle).
It's all muddied somewhat in digital land because 5 micron pixels have been around for ages, yet resolution has gone up... but when you think about Bayer masks and microlenses you realise quoted pixel sizes tell you the relative light gathering power, not how big a spot they can sample.
Ronald M
Veteran
Like houses and cars, bigger is better and costs more. Add in taxes and repairs and insurance and you know the drill.
1200 sq feet is an adequate home. Chevrolet will get you there as fast as Ferrari and it does not need a visit to Tony every month for work. I almost bought one but management said no. So I drive my Buick & Chevy. They do not need engine removal tune up every few years for $15,000.
So it comes down to purpose of photo, wall mural you can sell or something that lives in your I Mac or family album. Bigger is better but consider your end use.
1200 sq feet is an adequate home. Chevrolet will get you there as fast as Ferrari and it does not need a visit to Tony every month for work. I almost bought one but management said no. So I drive my Buick & Chevy. They do not need engine removal tune up every few years for $15,000.
So it comes down to purpose of photo, wall mural you can sell or something that lives in your I Mac or family album. Bigger is better but consider your end use.
Bill Clark
Veteran
Pretty nice photographs can be made with a cell phone.
Bigger isn’t necessarily better. I look in the mirror and think, “I need to go on a diet.” Just like my cameras! Smaller is the place to be.
Bigger isn’t necessarily better. I look in the mirror and think, “I need to go on a diet.” Just like my cameras! Smaller is the place to be.
markbakovic
Member
The camera that takes the best photo is the camera that's there when the photo is taken. If a small camera is where the moment is and Ansel's 8x10 is at home in the cabinet...
farlymac
PF McFarland
This is just another one of those imponderables that will never get settled. That is, until the ultimate do-everything camera is designed, and it only weighs a few ounces, and costs less than $500.
But for now, I believe the size of the sensor and camera needs to be matched to the task at hand. On a trip where you aren't going to have time for any serious photography, then snap away on the phone or cheap compact. It will be good reference material for later adventures, especially if one gets the chance to return to the area.
PF
But for now, I believe the size of the sensor and camera needs to be matched to the task at hand. On a trip where you aren't going to have time for any serious photography, then snap away on the phone or cheap compact. It will be good reference material for later adventures, especially if one gets the chance to return to the area.
PF
michaelwj
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I disagree
I think it is settled. Bigger is better providing your technique (and back) is up to it, but smaller will often suffice, especially with modern digital.
This is true as long as it doesn't lead to laziness and using the wrong tool always just for convenience's sake.