DOF Question

I have a question about the shape of the DOF plane in which objects are in focus. Is it flat or is it curved?

Let me explain my question a little better by describing what I want to do; I want to do a "little planet" shot like the one I have done here:

http://backup.cambridgeincolour.com/...k%20Bubble.jpg

The thing is, I would like to do it with a larger group and a shallower DOF, so do I:
1) Line them up on the same plane by lining up on the midline of a football field
or
2) Have them equal distance from me by taking a length of twine and making an arc with my camera position at the radius node

My inclination is that I should line them up on the same plane because the sensor onto which I am focusing them is flat. Yes, I am aware that I know enough about optics to ask difficult questions, but not enough to solve the problem...hopefully someone will have a good answer.

-D

Derik

I presume you just took a shot of a line of people then used polar coordinates in Photoshop, or some other package (?) to get the circle (I say that because the tops of the bodies look too wide). Is that right? If so, and you just want shallower DOF just choose a larger aperture - say f4 - on your camera when you shoot it. Or have I misunderstood you?

This is the basic EXIF data:

Quote:

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Camera Maker: NIKON CORPORATION
Camera Model: NIKON D60
Lens: 18.0-200.0 mm f/3.5-5.6
Image Date: 2009-12-23 16:21:57 -0500
Focal Length: 20.0mm (35mm equivalent: 30mm)
Aperture: f/5.6
Exposure Time: 0.010 s (1/100)
ISO equiv: 100
Exposure Bias: none
Metering Mode: Center Weight
Exposure: aperture priority (semi-auto)
White Balance: Auto
Light Source: Unknown
Flash Fired: Yes (Auto, return light detected)
Color Space: Adobe RGB (1998)

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