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Category: Digital Cameras

Photography Question 

William Koplitz
 

Size of Digital Sensors


I'm wondering why the camera manufacturers didn't standardize the size of digital sensors to produce an 8x10" print or a 7.5x9.5" size. It looks like they took the same dimensions as 35mm film and went with that, which I think is short sighted. The film world tries to operate around the 8x10" print, not a 6.5 x 10" print. It seems that all they would have to do is add sensor to the narrow sides. I'm hoping there are people who have insight into digital sensor size.


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May 26, 2005

 

Jon Close
  8x10 is no more a standard than is 5x7, 6x7, 4x6, 11x14, or any other common print size. Most digital cameras, including the Olympus line of DSLRs, are formatted in 4:3 to match the dimensions of common computer monitors. That Canon/Nikon/Minolta/Pentax adopted the 2:3 format of 35mm film for their DSLRs is due to the overwhelming familiarity of users with that format, and because their existing SLR lens inventory is optimized for that format.


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May 26, 2005

 

William Koplitz
  If you work in 4x5" or 8x10" film, you will see that there is an 8x10" standard for those sizes, and if you've worked in 5x7", you will see that there is an 3.5 x 5" a 5x7", and an 11x14" size that speaks to that format. I guess by standard, I'm speaking of getting the most utility out of the paper trim sizes that are on the market.
Why would I want to buy 8x10" or 8.5x11" inch paper if I have to trim and throw parts of it away? Wouldn't it have been better to match the sensor to the paper rather than to an arbitrary size left over from old technology that never spoke to the standard photographic paper sizes for 35mm either, or to a monitor size which is changing and evolving? I just don't know.


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May 26, 2005

 

Kerry L. Walker
  Paper sizes have never been standardized to fit the film format (with the exception of 4x5 and 8x10 large-format film). Many years ago, when I was young (too many years ago), the film sizes were 6x6 (2-1/4 x 2/14) and 24x36 (35mm). You just learn to allow for the crop when you take the picture.


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May 26, 2005

 

Andrew Laverghetta
  Something that I noticed that I found odd had to do with a Kodak Easyshare camera that I bought on impulse early this year. It defaults at the 8x10 kind of ratio (is that 4:3?), and then you can choose to select the 3:2 as if it was 35mm. The thing that's interesting about that is that it's not really 3.2 MP anymore, right? Just figured I'd put that out there.


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June 02, 2005

 

Shawn Wilson
  Well, with your easyshare it still could be depending on how it uses the sensor. If it uses the whole sensor for one, and shrinks one dimension to make the other, then yes, it's losing resolution.

However, if they planned it right both formats could be a full 3.2 if neither uses the whole sensor, but one uses the full width and partial height, the other use full height and partial width.

One quick and dirty way to tell is to look at the image size... just multiply the two dimensions for the MP. My Rebel XT shoots at 3456 x 2304 which makes it 7.96 MP (marketed as 8MP, close enough).

I call it quick and dirty, because it could be misleading. While I don't know of any cameras that do it, it would certainly be possible for a camera to write a file that has been upsized. So unless I could prove that NO camera does that, then I'll consider the dimension test to be a rough one.


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June 03, 2005

 

William Koplitz
  Isn't it also kind of odd that the HD TV standards people selected the letterbox ratio (I believe it was originally a technicolor ratio). Why do the manufactures think we want that ratio? Is someone going to start manufacturing 7x10 paper?


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June 03, 2005

 

Jon Close
  HDTV aspect ratio is 16:9, which matches that of the most popular wide-screen motion picture format - Panavision. There is also a wider Panavision format of 2.35:1, and older/wider widescreen formats such as Cinerama and CinemaScope.

The H ("HDTV" or full frame) setting of APS film/cameras is 16:9 and printed as 4" x 7". The Panorama setting returns crops printed as 4" x 11".


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June 03, 2005

 

Phillip Corcoran
  I think the so called 'standardisation' of print sizes which some argue does not exist, came about as a result of the readily available 'off the shelf' frame sizes you can pick up in any photo shop -- and this certainly includes 4x6,6x8 and 8x10 inches, all of which are available ready-made for you to pop in a photo of that size. From that it's easy to see how those corresponding print sizes have been dubbed as 'standard', for want of a better word, and I for one understand it's meaning even if it's never been officially adopted.


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January 27, 2006

 

William Koplitz
  I guess what I was trying to say is that if you work in photographic sheet paper, there is 5x7", 8x10", 8.5x11", and 11x14" etc. The 35mm frame size in slr cameras isn't in any of these ratios. The paper manufacturers never made a paper to give you a full frame from a 35mm negative. And now with digital it continues. The Nikon D1x frame is 10.237 x 6.533 at 300 dpi. Why? I think that 35mm lens coverage is probably the right reason, but why do we have to continue this with digital? Sensors can come in many sizes. It seems that the new technology could improve these ratios. Why the powers that be decide on 16:9, what was the advantage? Did they test this on viewers or did they just decide that's what it was going to be or is there some kind of technological limitation that we don't know about?


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January 27, 2006

 

David A. Bliss
  Here is a link to an article which should explain why 35mm was originally chosen as a film standard.

http://fotogenetic.dearingfilm.com/golden_rectangle.html

Any lab should offer 8x12 (the 3:2 aspect ratio of 35mm film and most SLR sensors) as a standard print size. Mats with an 8x12 opening are harder to come by, but this isn't an issue if you cut your own mats. I don't worry much about the aspect ratio when I am shooting or cropping. I use what is best for the shot. Then, I add to the canvas in Photoshop to equal a standard lab print size. For example, if a picture ends up cropped to 7x11 (just as an example), I then increase the canvas size to 8x12 with a nuetral background color, and have the lab print it at 8x12. This keeps the picture at the aspect I want, keeps printing cost lower because it is a standard lab print, and gives me some extra area for attaching to the mat.

The problem you are running into is with home printing, I am guessing. You have your logic backwards. 35mm, or 3:2 aspect, has been around a long time. What you should be asking is why the companies who make photo printers are trying to force you into a "standard" size.


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January 27, 2006

 

William Koplitz
  No, not really, I asking, "Why we can't we move forward?"


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January 27, 2006

 

Shawn Wilson
  It seems as though you think 'moving forward' is acomplished by the photography world changing adapt to new the digital camera world toys. That logic seems flawed though.

Digital camera makers may have plenty of reasons for making sensors of different sizes, but none of those reasons are photography based. They are price, manufacturing, etc... reasons.

What needs to happen is for digital camera makers to mimic a 'real' camera by using a 35mm sensor size and to stay in line with how photography has long been arranged.

Unless there is some good reason to change aspect ratios or sensor size, then why change something that isn't broke? Why should frame makers, photo processors, and others all have to adjust to the newest whim of some cheap digital camera?

Honestly is like telling the US to remake all of it's roads if today's cars want a much larger wheel base. No. Car makers make cars to fit the road because that's what's out there and there isn't any good reason to change something that large. Digital camera makers should follow the same logic.

If frames are sold at 3:2 ratios, then the camera should take 3:2 pictures.

If there is some compelling reason to change that, then present the case and then move forward... but movement for the sake of movement is not forward. Changing just for the sake of change has no purpose. Only when some good or improvement is furthered is the change worthwhile.

This really is a moot point though, we're all consumers here... not manufacturers... so lets just move on shall we...?

To your original question though... the REASON digital camera makers choose the sizes they do comes down to cost, convienience, and maybe even to cater to those who have 8x10 photo printers at home. Maybe there are others, but those are the big ones I'm sure.


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January 27, 2006

 

William Koplitz
  Do you speak for all manufacturers or just the ones you buy from?


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January 27, 2006

 

Shawn Wilson
  White papers, press releases, new product articles... that's where you'll find their reasons for using certain sensors. Mostly what you'll find is that the manufacturer made no specific thought toward the aspect ratio. Until you get to SLR level cameras that is.

In the end though, it comes down to what YOU want and what YOU'RE willing to work with. If you require a 4:3 image sensor then find one and go with it. If you want a full frame 3:2 sensor, then find that and go with it.

Personally, I'm less concerned with the aspect ratio and more focused on image quality. I can fix the aspect ratio with cropping or resizing and realistically we're talking about loosing less than 1% of your image area in either case at worst.

Knowing your equipment and planning your shot will make sure you don't have to worry one bit about the aspect ratio of the sensor.

In truth, I really don't see why it's even that big of a deal seeing as how we've lived with the standard sizes this long and they never have preserved aspect ratio (4x6, 5x7, 8x10 all have different aspects yet we use the same 35mm source to make those prints).


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January 27, 2006

 

David A. Bliss
  I see now that there is confusion between size and aspect ratio. Reading Williams response more carefully, he was wondering why the Nikon D1x frame is 10.237 x 6.533 at 300 dpi. That has everything to do with the size of the sensor, not the aspect ratio. The sensor on the Nikon D1x only captures enough pixels to create a 10.237 x 6.533 print, but it still has a 3:2 aspect ratio. To print an 8x12 picture, the original photo needs to be enlarged (tools for enlarging digital photographs is another discussion).

This is no different than a 35mm negative. The original photograph is captured on a piece of film that is 24mm x 36mm, so to get a 4x6 print, the original picture must be enlarged. This is an issue of size. Aspect ratio determines what size the print needs to be to keep any of the picture from being cropped.

The discussion as to why 8x10 and 16x20 seem to be "standard" print sizes has been discussed ad nasium long before the advent of digital photography, and is relevent to aspect ratio, not size.

For the most part, digital SLR cameras have maintained the 3:2 aspect ratio. A lot of P&S digicams have gone to a 4:3 ratio, and this seems to be because the size of a standard monitor or TV has a 4:3 ratio, so the pictures can be displayed on a monitor without any "filler" space. The largest print size that can be produced by any camera has to do with how many pixels it captures. The more pixels captured, generally, the larger the print can be without using enlarging software.

The funny part of all of this, is all of these aspect ratios still do not equate to an 8x10 print, which has an aspect ratio of 5:4, which means even using a 4:3 ratio camera, you still can't print an 8x10 without adjustments. Seems the photo industry just can't seem to get anything on the same page!


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January 27, 2006

 

William Koplitz
  David, thank you. That was exactly the point I wanted to make. It seems that these camera bodies have the space to create the 5:4 aspect ratio, my question was, why don't the camera manufacturers do this, it just seems to make sense to me.


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January 27, 2006

 

David A. Bliss
  William, I understand exactly what you are saying, and understand your point. But with all of that said, I prefer the 3:2 ratio, and generally try to fill the frame of my SLR when shooting. I like the way the thirds line up better, and after reading about how the 3:2 ratio was designed with the golden rectangle in mind, I understand more as to why I like it better. I started matting my own pictures, so I don't have to worry about custom matting, and like I said before, I enlarge the photoshop canvas to a "standard" print size. I don't print my own photos, I prefer to have it done at a lab. I do also have many pictures that I have cropped to 8x10 ratio, because that is the ratio for most magazines. There is one glaring exception. One of the most highly touted photo magazines in the world, National Geographic, has a 3:2 aspect ratio. Guess they realized the importance of being able to use the full frame of a 35mm camera without cropping.

Also, Shawn, you said you are losing less than 1% when cropping. To crop from 8x12 (the enlargement of 3:2 ratio) to 8x10 (what is being called standard) is a little over a 16% loss of viewable area. Personally, I would like to use that much extra space.


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January 27, 2006

 
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