iPhone vs. DSLR - a photo on Flickriver

iPhone vs. DSLR

The photo on the left is from my iPhone 3Gs (3 megapixels), and the photo on the right is from my Canon EOS 7D (18 megapixels) using a 15-85mm lens, zoomed to 85mm Click on image to enlarge it.

Angle of View: You'll note that the yellow poppy in both photos is the same size, whereas the two red poppies are enlarged on the iPhone photo. You'll also note that the iPhone photo includes more of the background behind the poppies. This is because the iPhone's "normal" lens has an angle of view of about 45 degrees, whereas the Canon's 85mm is about a 2X telephoto on this camera with about 1/2 the angle of view (about 23 degrees). Selecting a longer focal length allows me to narrow my vision and be more selective in what appears in my background.

Depth of Field: But, the big thing everyone notices right away is depth of field: what is in focus, and what is not. The iPhone has a 3.85mm fixed focal length lens, so it has incredible depth of field (DOF). The hairs on the stems of the two red poppies are tack sharp from the flower, almost all the way to the ground, whereas none of the hairs on the Canon shot are in focus. The EXIF info shows that both images were shot at 1/125 second shutter speed but the iphone's aperture was wide open at F2.8, and the Canon lens' aperture was stopped down 1/2 stop (from F5.6) to F6.3

So why is there such shallow DOF with the Canon shot, even though it was taken with an aperture setting that is 2.5 stops smaller? That's because the aperture opening on the iPhone was only 1.375mm in diameter (3.85mm divided by 2.8) compared to an aperture opening of 13.492mm in diameter (85mm divided by 6.3) for the Canon lens. And this is all because the image sensor size for the iPhone is less than 1/2 the size of your little fingernail, while the Canon's 7D image sensor is an APS-C size that is more than twice the size of your thumbnail.

My work flow: I often take images with my iPhone first, and if like the shot, I'll pull out the "big guns": either my Canon 7D or my Canon 5D Mark II with it's full-frame image sensor (allowing for even shallower DOF). With these two DSLR's I can choose a focal length (angle of view) and set the aperture for the DOF I want.

iPhone Rules (in some cases): Occasionally, I'll need the incredible DOF that a short focal length lens provides. This keeps everything in focus. Short focal length, wide angle lens on your DSLR will do this too, but you also get wide-angle distortion (close objects are overly large compared to distant objects). The iPhone's somewhat "normal" angle of view lens give limited distortion that is similar to what our eye sees.

Taken on: July 27, 2010

Tags:

flowers

bloom

poppy

poppies

red

yellow

orange

plant

botany

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Sets appears in: • iphoneography

Camera: Canon EOS 7D, f/6.3, 1/125 sec, 85mm, ISO 400 (more info) (hide info)

Camera:	Canon EOS 7D
Aperture:	f/6.3
Exposure Time:	0.008 sec (1/125)
Focal Length:	85mm
ISO:	400
Exposure Bias:	-1/3 EV
Flash:	Off, Did not fire
Exposure Program:	Aperture-priority AE
Exposure Mode:	Auto
Metering Mode:	Center-weighted average
White Balance:	Auto
Color Space:	sRGB
Software:	Adobe Photoshop CS4 Macintosh
Show full info

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