Why are sensors rectangle, not square?

[Ikinaa]

So...
There has been square films, like 6x6
Then there has been rectangle films, like 35mm, 110, etc
the lens is round, so to have a maximum of picture, film should be square (ok it should be round, that the lens would cover 100% of the film.)
If film/sensors were square, no need to turn the cam for 90degrees to get a portrait... No need for BigEds (except for the extra battery power...)

Anyone has got an idea why film/sensors mostly tend to be rectangle instead of square?

[BearSummer]

Hi Ikinaa,

The 35mm format is 36*24mm = 864 sq mm
square format for a 35mm lens would be 30.6*30.6 mm = 936 sq mm
If you were then to crop the square down to a 3:2 ratio your image would be 30.6*20.4 mm = 624 sq mm or 72% of the maximum 3:2 aspect that would be possible within the limitations of the image circle. Basically put, if you give someone a square sensor and they then crop the image to a 3:2 ratio you lose 28% of the area available to you if you started of with the 3:2 ratio.

Another way of looking at it....
Canon 1Ds image is 4064*2704 11Mp
square would be 3453*3453 11.9Mp
square cropped to 3:2 would be 3453*2302 7.9Mp

When using 35mm lenses manufacturers have generally kept to the old aspect ratio of 3:2, even when using non-full frame sensors (D60/1D etc). This was probably done because those people who already own lenses or are used to P&S camerase are used to the 3:2 aspect ratio. Some manufacturers are trying to dring out the 4:3 ratio in similar sized bodies, only time will tell how well this goes. You do have the option to use a square format, but currently it is only (AFAIK) available where square format was already used. You can get medium format digital backs that have square chips but these are usualy very expensive.

I guess the bottom line is that they are selling into an existing market that uses 3:2 aspect ratio so that is what they know will sell.

Best regards

BearSummer

[robertwgross]

Anyone has got an idea why film/sensors mostly tend to be rectangle instead of square?

This is a trick question, right?

Because one side is longer than the other side.

It's traditional.

---Bob Gross---

[Ikinaa]

Thanks BearSummer,
that makes sense.
What did the first photographers (150+ years ago) use? Square or rectangle glass plates?
Why are there still 6x6 or 4.5x4.5 films?
the 2:3 ratio is easy to understand : approx the golden cut (call it like that?, fibonacci series, etc)
Who had the idea?
What's the story behind all these film sizes ? 135, 110, 35, 6x6, 4.5x4.5, etc.

This could make a good photo-history-thread...

[Ikinaa]

Anyone has got an idea why film/sensors mostly tend to be rectangle instead of square?

This is a trick question, right?

Because one side is longer than the other side.

It's traditional.

---Bob Gross---
hmmm... tend is perhaps the bad word then .
Here's the question : Anyone has got an idea why film/sensors mostly are rectangles rather than square?

[Big_B]

Anyone has got an idea why film/sensors mostly tend to be rectangle instead of square?

This is a trick question, right?

Because one side is longer than the other side.

It's traditional.

---Bob Gross---

:lol:

[Big_B]

Seriously though, I guess tradition plays a big part in it. Also, retangular is more in keeping with the proportions of your monitor... printer... paper... picture frames etc. I suspect there is an asthetic explanation behind this pattern.....

BB]

PS. This might all be drivel. I'v had 3 hrs sleep in the last 48 hrs. Bit sleepy now.

[nosquare2003]

What did the first photographers (150+ years ago) use? Square or rectangle glass plates?
Why are there still 6x6 or 4.5x4.5 films?


I'm not old enough to tell. But previous DLR, people had to look down the viewfinder to take photos. I can't image if they would use a "portrait" style to take photos. (Now the DLR's viewfinder can be similar to SLR.)

[ssim]

Another "life: question. I don't know the answer but I'm sure it can be partly answered as above, with the relationship to printing sizes.

I knew a photographer that used a hassleblad (6X6cm) and was always complaining that he needed to make sure that he left enough room in the image for cropping to the standard print sizes. He evenutally converted to 6X7 format which saved him the hassle of doing this on all his shots. He says that he didn't notice any difference in quality between the hassleblad and the mamyia ProS67. Mind you he bought nothing but the best glass.

[Andy_T]

the 2:3 ratio is easy to understand : approx the golden cut (call it like that?, fibonacci series, etc)


That is most likely the reason for it all.

Before photography, there were drawings.

Before drawings, there were wall paintings.

I think that the 'golden cut' is attributed to the Greek artists and a basic measure of any decent greek temple.
It is a proportion derived from nature, pleasing to the eye and more interesting than a square.

This could make a good photo-history-thread...

You see, it goes back further than that :wink:

Best regards,
Andy

[Ikinaa]

the 2:3 ratio is easy to understand : approx the golden cut (call it like that?, fibonacci series, etc)


This could make a good photo-history-thread...

You see, it goes back further than that :wink:

Best regards,
Andy

Yep... remember the cams of the flintstones...? (bird in a box carving the picture...) Now that's old... :wink:

[Scottes]

From Leica's page on Oskar Barnack (http://www.leica-camera.com/kultur/mythos/barnack/index%5Fe.html), the inventor of the 35mm camera:

At the time, the miniature film format of 24 x 36 mm was created by simply doubling the cinema film format.

So the real question is, why was cinema film the size it was?


And this page (http://encyclopedia.thefreedictionary.com/35mm%20film) might have the answer, but there's too much to follow.

[CyberDyneSystems]

The rectangle is pleasing.. llok up golden rectangles and what not.. the composition part of it lended itself to more dynamic prints..

However.. it is clearly still a hold over at this time.. as the CCD sensor could be square.. and leave the framing up to the post process crop. For those that don't want to post process a crop.. the camera itself could be set to use the square CCD in either a Landscape crop or portrait crop with a switch... (for an SLR the viewfinder would be an issue but for EVF this would be automatic.

My guess.. this is another of those things that WILL change.. as we migrate from a "Digital as younger brother to Film" to a "Digital has matured to it's OWN artform and technlogy" world.

[PacAce]

My guess.. this is another of those things that WILL change.. as we migrate from a "Digital as younger brother to Film" to a "Digital has matured to it's OWN artform and technlogy" world.

How about a 16:9 (wide-screen) aspect ratio? :) Remember the 3 choices for printing APS films (Classic, HDTV and Panoramic)?

[Andy_T]

However.. it is clearly still a hold over at this time.. as the CCD sensor could be square.. and leave the framing up to the post process crop. For those that don't want to post process a crop.. the camera itself could be set to use the square CCD in either a Landscape crop or portrait crop with a switch... (for an SLR the viewfinder would be an issue but for EVF this would be automatic.

My guess.. this is another of those things that WILL change.. as we migrate from a "Digital as younger brother to Film" to a "Digital has matured to it's OWN artform and technlogy" world.


Two points here ...

Why pay more money for a larger sensor if you only use a part of it most of the time?
The crop is a vital part of the picture's message and quality. Most likely not all of it will be done in Photoshop.


How about a 16:9 (wide-screen) aspect ratio? :) Remember the 3 choices for printing APS films (Classic, HDTV and Panoramic)?

That was the invention of the crop factor :lol:

We did the same question with the round sensor, remember? :wink:

Best regards,
Andy

[CyberDyneSystems]

Andy,

Whats more expensive though..

A slightly larger (square) CMOS sensor,.. or all the beels and whistles that we now need to be able to take portrait aspect photos with our SLRs?

No need for a vetical grip.. no need for all that flash bracket hockus pocus.. complete flexibility.. either set the camera to take portrait or landscape.. but I would persoanlly ALLWAYS shoot full sensor square and crop as I saw fit. (again.. this aspect of it is more of the "breaking" from the film tradition that some will have a harder time getting past)

Anyway.. it seems to me that the chip solution will in the long run be at least as affordable if not cheaper than vertical grips.. and it will cetainly make the picture easier to take!

[Chazs]

Why are sensors rectangle, not square?

The real reason.......

'cause you can't find square paper! :wink:

[Andy_T]

Andy,

Whats more expensive though..

A slightly larger (square) CMOS sensor,..


Canon pays for that when they manufacture the camera, and they might find it more difficult to sell an expensive camera than a cheaper one ...

or all the beels and whistles that we now need to be able to take portrait aspect photos with our SLRs?

No need for a vetical grip.. no need for all that flash bracket hockus pocus.. complete flexibility.. either set the camera to take portrait or landscape.. but I would persoanlly ALLWAYS shoot full sensor square and crop as I saw fit. (again.. this aspect of it is more of the "breaking" from the film tradition that some will have a harder time getting past)


YOU pay for all these accessories when you want to take portraits :wink:

Best regards,
Andy

[stopbath]

I like the idea of a square sensor. Could shoot square, or in portrait of lanscape mode with a turn of a wheel (Naturally the finder will relay that information with a matt glass or black frame that changes the image dimentions as needed.)

Could be nice for portait style movie clips too! Don't adjust your TV, the black bars on the left and right of the screen are normal...

Ok, Canon...

[Persian-Rice]

I believe that digital backs have square sensors, correct me if I am wrong..................

[CyberDyneSystems]

Andy,

Whats more expensive though..

A slightly larger (square) CMOS sensor,..


Canon pays for that when they manufacture the camera, and they might find it more difficult to sell an expensive camera than a cheaper one ...

or all the beels and whistles that we now need to be able to take portrait aspect photos with our SLRs?

No need for a vetical grip.. no need for all that flash bracket hockus pocus.. complete flexibility.. either set the camera to take portrait or landscape.. but I would persoanlly ALLWAYS shoot full sensor square and crop as I saw fit. (again.. this aspect of it is more of the "breaking" from the film tradition that some will have a harder time getting past)


YOU pay for all these accessories when you want to take portraits :wink:

Best regards,
Andy

Not on the 1D, 1Ds or MkII.... or D2h,. or D1H or D1X...


PR.. yes many digital backs are square..

[adas]

I think this is because our viewing field is larger on the horizontal axis then on vertical.
Why? Because we are two eyed beings.

[Moppie]

I think this is because our viewing field is larger on the horizontal axis then on vertical.
Why? Because we are two eyed beings.



Which is exactly why we prefer the golden rectangle 8)


Out of the hundreds of thousands of photos taken by all the members here, who has ever made a square crop of an image?

The human brain does not like squares, and its reflected in everything humans create and design.

Take a look around your apartment or house, and tell me how many square things you can see.

Everything, from your computer to your kitchen shelves, to your appliances, to your CD case's even your books will be either round or retangular.
If you find something you think might be square, go measure it. I bet it isn't, or if it is it will have some other feature that breaks up the square shape.