Why are sensors/film rectangular instead of square?

[Les Olson]

Sensors are rectangular because no one, ever, anywhere, has liked square pictures. There are no attractive square building facades. There is only one square flag in the world (and that has a non-square internal design). Squares are unappealing.

The exact proportions of conventional film and sensors, on the other hand, are arbitrary (except 13:9).
--

'Some of the money I spent on booze, women and fast cars, but the rest I squandered' - George Best

 

[Mark Smith145430]

there are
many good and valid reasons why it isn't used.

And there are no reasons why it should be.

CD album covers? and just about any situation that calls for a square image.
Or you just like it?
I think it's great for portraits.
Mark

--
http://www.photo-utopia.blogspot.com/

 

[refrigerator]

Okay. So a square occupies the most "real estate" of a lens. Why does it make sense to have rectangular chips bewilders me.

 

[DonAvebury]

I took an album cover (12"x12") with the $200 Yashica version of that camera.

 

[Astro Landscapes]

By the way it's mathEmatical. ;-)

My point is, you drove yourself right into the ground with that very first statement- "from a mathematical standpoint...".

Photography is an art. Artistic composition FREQUENTLY lends itself to wide, landscape / panoramic framing. Often times I wish I had a 9:16 frame, or heck just give me 1:2!

I do have some square photos that I really love. But I almost ALWAYS find that 2:3, or 1:3, is fantastic for composing powerfully, especially in nature images.

=Matt=

--



Cameras capable of making great photographs have become commonplace these days, but photographers have not. While technical innovations have made photography ever easier in recent decades, the art of producing images that other people will care about has become even more formidable. Galen Rowell

 

[nickoly]

Why does
it make sense to have rectangular chips bewilders me.

I'm not surprised.

But the reasons why 99.99% of the cameras ever made have rectangular format are twofold

1. it is more efficient, that means costs less

2. it is what people want, and thus reasonably expect

 

[dj_nme]

From a mathematical perspective, won't a square (also a rectangle)
and a rectangle yield the same area in a lens circle? It seems it
would be more appropriate to use square frame instead of a
rectangular.

For a fixed width of film strip that the frame length (along the roll) can be made greater to make larger negatives.

With digital SLR an RF cameras, the manufacturers are essentially re-using their R&D investment in their existing lenses and making the sensor to fit the constraints of their camera and lens mount designs.

I don't really know, but my guess with FourThirds is that the group wanted to match the aspect ratio of a standard computer monitor (which is 4:3) to go with their much hyped "all digital" standard.

 

[hvtran]

From a mathematical perspective, a 4-sided shape with the maximum area that will fit in a circle is actually a rectangle

 

[sherwoodpete]

Okay. So a square occupies the most "real estate" of a lens. Why does
it make sense to have rectangular chips bewilders me.

It only makes sense if you want square pictures.

For any rectangle such as the common 4:3 or 3:2 shapes, a square sensor is inefficient.

Say for example the image circle is 1000 pixels in diameter. The corresponding square sensor is 707x707 pixels.

Now, fit a 3:2 rectangle into the square, it will be 707x471 pixels. But the largest rectangle we could fit in the image circle is 832x555 pixels.



Apologies for repeating what has already been said.

Regards,
Peter

 

[Steen Bay]

Facts are that within the same 43,3 mm (FF) image circle, instead of
a 24 x 36 mm sensor we could have a 30,6 x 30,6 mm sensor, with a
8,4% bigger area.

Facts are that a 30.6mm sensor requires 46mm of "back focus" (clear
space between the rear element of the lens and the focal plane).
You've got about 5mm for the shutter, and 43.3mm to accommodate the
swinging SLR mirror. But lenses built for existing 35mm SLRs only
have 39mm of back focus, because their frame is 24mm high, not 30.6.

Facts are that a 50mm f1.8 normal with a 39mm back focus is a nearly
symmetric double Gauss design that is both high performance and low
cost. But a 50mm f1.8 normal with a 46mm back focus has to be built
as a retrofocus lens, a wide angle design that is larger that a
double Gauss, and will either cost more for the advanced design
needed to compensate for aberrations added by the retrofocus design,
or perform much poorer than the double Gauss. This is also true of
the wide angle lenses.

Facts are that my Nikon 300mm f2.8 and 200mm f4 macro have built in
24x36mm rectangular baffles and can't project a 30.6mm square image,
and my 14mm has a built in "petal" lens hood that similarly only
allows 24x36mm images. These baffles and hoods are not removable.
Facts

Facts are that although the area of the mirror for the 30.6mm square
is only 8.4% larger than for a 24x36mm, the angular moment is 2.64
times higher (30.6/24)^4 so there's over twice the mirror slap
vibration, longer mirror blackout times, and considerably more noise.

Facts are that I have to crop a lot more of a square than a rectangle
for my work, so that 8.4% bigger area is a total waste.

That's a lot of good reasons why a square sensor won't work in a DSLR, but I imagine it implemented in the coming 'EVIL' camera without mirror, so no problemo

And facts are that I very much prefer the square format. Instead of just using 24 x 24mm from the existing FF sensor, a 30,6mm square sensor would give me 62,6% larger area / more pixels. That's a lot!

 

[ZorSy]

And why are glasses rectangular as well?
the answers are in optics of the human eye and our vision.

For those who wants to read more here is the link which talks why TVs are in the shape as they are

http://www.tvtechnology.com/features/Tech-Corner/Hoffner_features.shtml

cheers

 

[Steen Bay]

that is because you are blind as well as illiterate.

I was pointing out the 4:3 picture cropped from the square is
smaller in area than the rectangle within the circle. Furthermore I
also said that the inscribed square is larger than the 4:3 inscribed
rectangle.

No matter, what you say is still baloney. A square is the largest
rectangle that can be inscribed in a circle. As they get more
rectangular they get smaller, even though the hypotenuse is always
the same. Pythagoras worked that out some time ago. It might pay to
read him.

.. to use words like "idiots", "blind", "illiterate" and "balony" In an innocent debate about aspect ratios?

As you say yourself "A square is the largest rectangle that can be inscribed in a circle", and if you prefer (as I almost always do) a square format for the final image, then it makes very much sense to use a square sensor. Instead of just using 24x24mm from the existing FF sensor, a 30,6mm square sensor would give me 62,6% larger area / more pixels.

 

[Joe Lavee]

Regardless of mathematical formulas and horizontal ratio debate, the
fact is that during the film era, the square format was used by most
pros for the very simple reason, it offered versatility.
Hence, if the price was right, it would be the choice for most pros,
including myself.

Claptrap. There is nothing versatile about square format, All they do
is waste film and time.The main reason why 6x6 stayed on in the
professional arena is because the two main proponents, Rollei and
Hasselblad, were well made cameras that had Synchro Compur shutters.
The fact that they were square format was a coincidence, that sent
the former to the wall, and had the latter putting off the same fate
by adopting a rectangular format.
If a real professional wants versatility, he/she buys the bleeding
obvious, a Linhof.

Not accurate.

The Mamiya was a very good camera and the Bronica as well. Both were initially rectangular.
To gain larger acceptance by pros, both had to introduce the SQUARE format.
By the way, what does the pro do with the Linhof, shoots weddings???

 

[Kaustav S Saikia]

A single human eye sees roughly a 140-degree field horizontally and a 90-degree field vertically.
So a rectangular viewing format is more natural.

If you notice, ancient scrolls/paintings and modern magazine/newspapers etc all follow that format - and hence it's logical for film/sensors to do that too.

Added to that the golden ratio (1.3:1 or 3:2 approx) is aesthetically very pleasing (again due to the rectangularity of human vision).

Also note that a landscape panorama is more appealing to most people than a vertical pano ;P
--



http://www.photoshoot.in
http://www.flickr.com/photos/photoshoot/

 

[GaryDeM]

the answer is far more simpler than what has been suggested here.

why are sensors rectangular? because 35mm film is. why is 35mm film the shape, it is? because before there was still film of any kind there was movie photography. and that film was 70mm wide. when it came time to make film to fit the still cameras that was just being invented, there wasn't any. so they just took 70mm movie fim and tore it in half, that became the 35mm film size that was later sold by the billions. and that size has stuck around ever since.

truth is stranger than fiction.

 

[nickoly]

35mm still film was made from 35mm movie film. It just runs sideways instead of from top to bottom as it does in a movie camera. This goes some way to explain why the sprocket holes are on both sides. It also means the frame is twice the size, which is a nice idea. Fortunately, Mr Barnack was not lunatic enough to settle on 24 x24 format.

There were actually quite a few forms of film before then, but 70mm movie did not come out till about 1958.

when it
came time to make film to fit the still cameras that was just being
invented, there wasn't any. so they just took 70mm movie fim and tore
it in half, that became the 35mm film size that was later sold by the
billions. and that size has stuck around ever since.

truth is stranger than fiction.

 

[Joe Lavee]

The square format is indeed great for portraits.

It offers the versatility and the option to crop either horizontal, vertical or square, when the composition calls for it

 

[Joseph S Wisniewski]

morninglight wrote:

. BTW: both still exist

today, new.

Actually they don't. Rollei actually went bankrupt, and was
liquidated. Parts of their portfolio and property was bought by a
variety of companies, including Samsung and Franke and Heidecke.

Actually you CAN buy a new Rollei today:
http://www.adorama.com/RL28FX.html

You can buy a new Yashica, Polaroid, or Voigtlander, yet none of those companies are actually in business. They're just licensed "brands'.

And Franke and Heideke were the parent company of Rollei weren't they?

Not exactly. Two people named "Franke" and "Heideke" started a company that was known at various times as "Franke and Heideke", "Rollei-Werke, Franke and "Heideke", and just "Rollei-Werke". That all came to the end with the bankruptcy liquidation of Rollei in 1981. After that, the words "Rollei" and "Franke and Heideke" are just brand management.

Currently, a Danish bank called Capitellum owns the Rollei trademark, and has a company called "Rollei GmbH" that manages all "Rollei" brand products. Capitellum owns an entirely different company called "Franke and Heideke" that actually makes the Rollei brand medium format cameras, but not Rollei brand 35mm or P&S digital gear. Some of Franke's and Heideke's heirs are currently buying back "Franke & Heidecke GmbH, Feinmechanik und Optik" from Capitellum.

1920 - Paul Franke and Reinholf Heidecke set up "Franke and Heidecke" in Brunswick

1959 - Nikon introduces the "F" SLR. At this time, Rollie is at the top of their game, highly profitable, with over a thousand employees in Germany.

1960 - Reinhold Heidecke dies.

1962 - Franke's and Heidecke's heirs, eager to establish a name of their own, changed the name to "Rollie-Werke".

And that's basically the recipe for the death of Rollie, just at the time a strong competitor arises, they lose the founder's focus, and the heirs start squabbling, panicking, and running around in a dozen different directions.

1966 - Franke's heirs buy out Heidecke's heirs, but this does little to fix the total lack of focus. The heirs pursued a policy of slash and burn price cuts, and move a lot of manufacturing to Singapore. They engage in "cost saving" reduction of engineering, while demanding new products like a 6x6 SLR, 35mm cameras, slide projectors, the 2000 modular 35mm SLR with interchangeable backs, phonographs...

1979 - Rollei hits the courts, attempting reorganization. A fierce battle with creditors begins.

1981 - The battle ends: not "reorganization", but total liquidation.

1982 - "United Scientific Holding", a British holding company, bought what is sometimes referred to as ROR (the "remains of Rollei"), the facilities and patents from the liquidator. USH emphasized the surveying equipment side of Rollei's at the expense of the camera side.

1987 - Jos. Schneider Optische Werke Kreuznach bought ROR from USH, and split it into Rollei Fototechnic and RollieMetric.

1992 - Schneider spins off Rollie into an independent company.

1995 - Samsung buys Rollei. This does not help business.

1999 - Rollie's management and an investment banker buy Rollei from Samsung. This does not help business, either.

2003 - Near collapse, they sells Rollie to Capitellum, a Danish investment firm.

2005 - Capitellum splits Rollie into "Rollie GmbH", a brand management company based in Berlin, and "Franke & Heidecke GmbH, Feinmechanik und Optik" still in Brunswick in an old Rollei building. Rollie GmbH brands film, digital cameras, film cameras, and lenses made by many different companies. F&H F&O does manufacturing for Rollie, two LF camera manufacturers, Schneider, and a clock company, as well as many small companies. They are set up like a very large "job shop".

2007 - Capitellum closes the Berlin Rollie GmbH offices, manages the Rollei brand from their own offices in Denmark.

And the circle closes: four of Franke's and Heideke's grandchildren have been buying back F&H F&O from Capitellum. Let's hope they do better with it than their parents did in the 60s. The new F&H family business is is 70 employees (+ -10, depending on who you ask) about the size of the original F&H back in 1925. Apparently, 70 employees at F&H F&O are enough to manufacture the Rollie MF TLR and SLR bodies and the Rollie slide projectors, manage the brand, build clocks, and take in contract work.

This is basically similar to Hasselblad, who manufactures, markets, and services all the square format "classic" Blads the world currently needs with about 60 people.

Heck the square MF format industry, with its 130 people (some of whom have their attention diverted to make MF camera parts for Sinar, or build expensive clocks) makes the 1000 employee Leica Camera look big, even when you consider that some of those 1000 Leica employees make binoculars and spotting scopes, or manage the "Leica branded" Panasonic products.

Which pretty much answers the "why are there no square format DSLRs from the likes of Canon or Nikon?" question.

wizfaq

--
Rahon Klavanian 1912-2008.

Armenian genocide survivor, amazing cook, scrabble master, and loving grandmother. You will be missed.

Ciao! Joseph

http://www.swissarmyfork.com

 

[Joseph S Wisniewski]

I moved a paragraph of yours to the top of the post, so that this flows a bit better

That's a lot of good reasons why a square sensor won't work in a
DSLR, but I imagine it implemented in the coming 'EVIL' camera
without mirror, so no problemo

Good point. But I'd say it's more a reduction in problems than a total elimination.

Facts are that within the same 43,3 mm (FF) image circle, instead of
a 24 x 36 mm sensor we could have a 30,6 x 30,6 mm sensor, with a
8,4% bigger area.

Facts are that a 30.6mm sensor requires 46mm of "back focus" (clear
space between the rear element of the lens and the focal plane).

And EVIL addresses that one...

Facts are that a 50mm f1.8 normal with a 39mm back focus is a nearly
symmetric double Gauss design that is both high performance and low
cost. But a 50mm f1.8 normal with a 46mm back focus has to be built

EVIL addresses that one, too...

Facts are that my Nikon 300mm f2.8 and 200mm f4 macro have built in
24x36mm rectangular baffles and can't project a 30.6mm square image,
and my 14mm has a built in "petal" lens hood that similarly only
allows 24x36mm images. These baffles and hoods are not removable.

Now that one, we're stuck with. You can have a 24mm square sensor and use the full lens line, but 30.6mm is just not compatible with 24x36mm internal baffles.

I forgot to mention my 70-200mm f2.8 VR also has them. As do my manual focus 55mm f2.8 and 55mm f3.5 macro lenses.

I noticed the other day that Bryce's 500mm f4 Nikkor also has them.

Facts are that I have to crop a lot more of a square than a rectangle
for my work, so that 8.4% bigger area is a total waste.

And facts are that I very much prefer the square format. Instead of
just using 24 x 24mm from the existing FF sensor, a 30,6mm square
sensor would give me 62,6% larger area / more pixels. That's a lot!

Yes, and it would be great for you. The problem isn't that "people don't use square pictures" or "no one uses them" (as a couple of people on this thread mentioned), it's that "not enough people" use them. It's not a philosophical question of "does it have merit?", it's a pure business question of "can it sustain a company?"

As I summarized elsewhere in this thread

http://forums.dpreview.com/forums/read.asp?forum=1018&message=28348165

The sum total of people at Hasselblad and F&H currently building, marketing, and servicing square format cameras is 130. I bet the janitorial staff at Nikon or Canon is over 130 people. The smallest 35mm company, Leica Camera AG, employs 1000 people, and that was barely enough to get Kodak to build a sensor when they already had the basic cell and peripheral circuitry ready.

There was not a sufficient market for the 36mm square sensor designed almost 10 years ago to sustain production of that part. There is simply not enough market for a new square format camera to justify the design of a modern sensor in that size. The sensor company wouldn't recoup the tooling costs in the lifetime of the part. Kodak could build a version of the 5 micron cell sensor from Leica M8, Modul-R and original Oly E-1, but that one is horrendously expensive even at 490mm2 area (M8 is a 1.33x crop camera). With smaller than M8 quantities, but a bigger than M8 area of 937mm2, you're talking a frighteningly expensive camera.

And that's still only a 7 year old cell that can't do live view well enough for the full EVIL camera. Sony, Panasonic, or Samsung aren't going to put next year's cell into something with the low volumes of a square format.

The environmentalist term for this is "commercially extinct". In rare woods (I also build woodwind instruments), they use it to refer to species of tree that exist in such large quantities that they don't appear on the "endangered" or "threatened" lists, but no longer exist in forests with sufficient density and good road access to permit profitable harvesting.

The square format market is like that. You've got some customers, like a stand of trees way off the beaten path. But those trees aren't profitable enough to build the road needed to harvest them.

--
Rahon Klavanian 1912-2008.

Armenian genocide survivor, amazing cook, scrabble master, and loving grandmother. You will be missed.

Ciao! Joseph

http://www.swissarmyfork.com

 

[Joseph S Wisniewski]

there are
many good and valid reasons why it isn't used.

And there are no reasons why it should be.

CD album covers?

Definitely. And framed mirrors.

But at 5 inches square, and typically a 72 screen, the CD album cover does not justify the production of a square format camera. You can shoot album covers with a square crop from a decent rectangular format SLR. Heck, cropped rectangular is even fine for 12 inch square.

and just about any situation that calls for a square image.

I've run into very few of those.

Or you just like it?

And that's the key. Everyone has the right to like what they like. You can shoot and crop how you like. Heck, if you market it well, you may even make a living at it.

But square fans simply do not have the numbers to represent a viable market for new technology development.

I think it's great for portraits.

I'll take your word on that. I've never shot a portrait that I wanted to print as square.

--
Rahon Klavanian 1912-2008.

Armenian genocide survivor, amazing cook, scrabble master, and loving grandmother. You will be missed.

Ciao! Joseph

http://www.swissarmyfork.com