Smaller sensors do not have deeper DOF

[Jeff Donald]

Current thread Title:

Smaller sensors do not have deeper DOF

Statement from prior thread:

Originally Posted by Daniel Browning

My central point was the format with the larger sensor was capable of thinner DOF, because it requires a longer focal length in order to keep perspective and field of view the same.

Statement from current thread:

That large sensors are capable of everything that small sensors are when it comes to DOF, diffraction, and noise. I ran into a DP that wanted to switch from the 5D2 to the 7D because he thought it had an advantage in deep DOF.

In one case large sensors are capable of thinner DOF and in another thread large sensors are capable of the same DOF as small sensors. Needless to say you've created some confusion.

[Daniel Browning]

Originally Posted by Jeff Donald

Current thread Title:
Smaller sensors do not have deeper DOF

That's the best summary of the thread emphasis that I could think of.

Originally Posted by Jeff Donald

In one case large sensors are capable of thinner DOF and in another thread large sensors are capable of the same DOF as small sensors. Needless to say you've created some confusion.

I still don't see where the confusion is. Both statements are correct and happily coexist. Large sensors are indeed capable of both the same DOF as well as thinner DOF.

[Keith Moreau]

I, for one appreciate this thread. Thanks Daniel, for the insight here. I guess gather that your point is, if you can afford it and don't need a tiny camcorder, you're not giving up any advantages by getting the largest sensor camcorder possible.

If you get a large sensor camcorder, and wind up stopping it down to get the most DOF you can, are you risking a soft image because of diffraction? I experience a big drop in image quality with my EX1 when I go above 5.6 or so. With a larger sensor is less of an issue?

Thanks again.

[Daniel Browning]

Thanks, Keith.

Originally Posted by Keith Moreau

If you get a large sensor camcorder, and wind up stopping it down to get the most DOF you can, are you risking a soft image because of diffraction?

No, because diffraction scales with DOF. So no matter what method you use to get the DOF, whether fast f-number on a small sensor or slow f-number on a large sensor, the diffraction will be the same.

Originally Posted by Keith Moreau

I experience a big drop in image quality with my EX1 when I go above 5.6 or so. With a larger sensor is less of an issue?

It will be less of an issue at the same f-number. But it will be the same issue at the same DOF. Essentially, the relationship between DOF and diffraction is the same for all sensor sizes.