Aspect ratio

[film2shoot]

Has anyone heard of aspect ratio. I have been told that my images are being shot in an aspect ratio of 1.5 (4x6). I was told that most cameras shoot in a 1.33 ratio. Does anyone know how to change this in camera. I own a canon 10d. I can't seem to find it in the manal.

Thanks
Tim

[DC Fan]

Most digital SLR's mimic the old 35mm frame aspect ratio of 3x2, because they were originally conversions of 35mm SLR's and the habit never went away. Consumer point and shoots mimic the old American NTSC frame aspect ratio (which also was the standard computer monitor ratio until recent years) of 4x3. Most Canon DSLR's such as the 10D have adjustable resolution (rarely used) but the aspect ratio is fixed at 3x2.

[tonylong]

I typically put out three common aspect ratios: the native 2:3, which prints, say, a 12x18 print, 4:3, which prints to, say, 12x16, and 4:5 which prints to 8x10 or 16x20. What's convenient is that I can just set the desired crop aspect ratio in my software. I have an aspect ratio feature in my 1D Mk III but never use it. Your 10D would not have that feature.

[DStanic]

Even if you can change the aspect ratio (I could do this on my old Sony H5 point and shoot) why bother? You are just chopping off part of the image. Better off to have the whole thing and do it with software later, if you deside to do it.

[walternewton]

Yes you have an aspect ratio of 1:1.5 like most DSLRs, many point & shoots have a 1:1.33 ratio. Neither is better or worse necessarily, just different - your 1.5 image is more "long" than the more "square" 1.33 image - sort of like the difference between a widescreen TV and a traditional TV.

It's something to keep in mind when considering what you want your final image to look like - for example if you know you want to print an 8x10 - 1:1.25 aspect ratio - you're going to have to crop one or both ends to make your photo narrower relative to its height, so this is something to keep in mind when composing your picture.

[film2shoot]

Thankyou to all who responded, learn something new everyday.

[Tixeon]

I typically put out three common aspect ratios: the native 2:3, which prints, say, a 12x18 print, 4:3, which prints to, say, 12x16, and 4:5 which prints to 8x10 or 16x20. What's convenient is that I can just set the desired crop aspect ratio in my software. I have an aspect ratio feature in my 1D Mk III but never use it. Your 10D would not have that feature.

To expand on what Tony said, the following may help.

1.25:1 ratio = 4x5, 8x10, 11x14, 16x20 etc very closely.
1.40:1 ratio = wallet size, 5x7, etc...
1.50:1 ratio = 4x6, 8x12, 10x15, 12x18 etc...

Hope this helps....

[chauncey]

If one uses a different aspect ratio, is it cropped in camera or are you getting your full amount of MP?

[20droger]

The aspect ratio of a camera is a function of its sensor. Whatever aspect ratio the sensor has, that is the camera's "native" aspect ratio.

For Canon DSLRs, that aspect ration is 1.5:1 (3:2) in landscape mode. The same applies to Nikon. DSLRs using the four-thirds system, however, the native aspect ratio is 1.33:1 (4:3).

If your camera allows changing the aspect ratio in camera, it can only be done by not using all of the sensor. This is a cropping function. So NO, you will not be getting the full MP of the sensor when you use anything other than the camera's native aspect ratio.

This is why it is ALWAYS better to shoot with the native aspect ratio and crop in post-processing.

Naturally, if a shot is taken with cropping in mind, the shot should be framed to provide the best image after cropping.

[tonylong]

Something that I left out in my post: the 2:3 aspect ratio senors are physically larger in both dimensions, especially on the wide end, than other alternative aspect ratio sensors. What I'm getting at is that with our 2:3 sensors you always get more image. his shows up absolutely at the wider dimension: if you want to crop to any other common dimension you can do so by "shrinking" the wider dimension without losing anything in the other dimension.

What this means is that you can crop to just about any aspect ratio and still retain good resolution. When you shoot in 2:3, you can crop to, say, 4:5 by taking a little off of the longest dimension without losing anything from the shortest dimension. his holds true for any common aspect ratio since 2:3 is the "longest" astpect ratio in common use aside from panoramas.

Chauncey, cropping to an alternative aspect ratio always cuts out some of the image, so loses some of the physical resolution, but that is just a fact of life. Whether you do it in your camera or in software is up to you. I personally prefer to do it in software, plus I don't use DPP (which is the only software that would recognize the 1D aspect ratio selection, I believe).

[chauncey]

Thanks guys!