Depth of Field has nothing to do with image sensor size...

There's two things I'm concerned about with camcorder filmmaking - say I choose a brand new camcorder like the Panny TMC or whatever it's called, and the specifications are that it has a 3-41mm lens (35-420mm equivalent) with a 1.5-2.8 aperture. With the focal length, does that mean that if you zoom the lens all the way out for the 3mm (35mm) view, that the distortion will be as severe as a 3mm lens? And would the depth of field also have the same properties as a 1.5 3mm lens? To me, this somehow seems as though it wouldn't be true, the lenses on camcorders do not have as severely a rounded shape as on say a DSLR 3mm lens (that type of lens on a DSLR would practically be a sphere.) It seems that with that sort of camcorder, that you'd have to zoom all the way out to achieve a normal 35mm view - not a bad thing, but I'm worried about the distortion levels, and to a lesser degree, the depth of field.

Simply put, it's a subject I enjoy because I've always wanted to use small camcorders for my indie films as opposed to DSLR's.
 
Razz16mm said:
There is an aspect of DOF that comes into play with smaller formats and higher pixel densities. That is critical COC, or how small the smallest sharp focus point is. A 1080p 1/3" chip has a much smaller critical COC than say an AF100 would at 1080p. Effectively at the same focal lengths you will get a more rapid fall off in DOF with the smaller sensor, so this can compensate to some extent for the shorter focal lengths required for equal FOV. Where the difference is hard to overcome is with wide shots against close backgrounds. A larger sensor gives a more gradual and easier to control fall off.
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Good point. That's why I personally don't like very much the Canon 5D for shots in which you want to get a lot of depth of field (e.g shooting landscapes). Because of the big sensor on the Canon 5D and the fact that you are only sampling just 1080 pixels, well, the critical COC is not as small as the 'equivalent' one with a small size sensor (1080 too). So as direct consequence of sensor size, and sensor output resolution (1080 in our case) you cannot get very sharp neat images with that camera. The critical CoC is not small enough, and the fall off is not pronounce enough. Even when you arrange your shot to get a large DoF (small aperture, large FoV, large distance to subject), the Canon 5D doesn't produce sharp images in my opinion, the 'grain' is not small enough.

But it works very well with shallow DoF. Because in shallow DoF only few things are in focus, well it gives you the illusion that the image is sharp and high quality in that camera. But that judgment owes more to the fact that in shallow DoF most of the image is out of focus, so when only out-of-focus stuff is your point of comparison, well it's easy to conclude that what is in focus is very sharp. As soon as you close your aperture, etc, to get large DoF, you realize that you cannot get very sharp images with that camera. The critical COC is not small enough. It seems that 35 mm film size sensor is a sweet spot for HD resolution (e.g F3, Alexa, RED). Full Frame seems to be too big a size to properly cover a wide arrange of shots in HD resolution.
 
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Misleading thread name and DOF has "something",not "nothing" to do with sensor size,no need to confuse people.moving back and forth is not always an option besides youre changing perspective and its important too.
 
Snapper123 said:
There's two things I'm concerned about with camcorder filmmaking - say I choose a brand new camcorder like the Panny TMC or whatever it's called, and the specifications are that it has a 3-41mm lens (35-420mm equivalent) with a 1.5-2.8 aperture. With the focal length, does that mean that if you zoom the lens all the way out for the 3mm (35mm) view, that the distortion will be as severe as a 3mm lens?
Click to expand...

No.

Snapper123 said:
And would the depth of field also have the same properties as a 1.5 3mm lens?
Click to expand...

Yes.
 
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