I don't think that will make any difference Brian - what really determines dof is the physical diameter of the iris, though it's not normally looked at in such terms. That's the physical reason why f2 for a 2/3" camera is the same in dof terms as f4 on a 4/3 camera. (For the same angle of view.) Same iris diameter in each case - it's the differing focal lengths (to keep angle of view constant) that will define f stops.

I did a quick 2/3 to 35mm standard motion picture DOF comparison with the 2 stops and there is a reduction in DOF (not a huge one), However, with the smaller 4/3 I suspect, as you suggest, there's nothing much in it comparing f2 as against a f4 max aperture..

That adapter is way expensive. About the cost of the camera...

I still want to use an AF100 for a production sometime. For my uses I use a DSLR, but an ENG style cam with servo was needed in addition.

The 2/3" zoom lenses are even more expensive.

I suspect that an ENG servo controlled lens for the AF100 would cost more than the camera. The only way it could be cheaper is if it's a dual purpose lens that stills photographers can also use.

Way, way more expensive than the camera. New, prices start at $15K for a "decent" lens all the way up to $60K for the high-end in both controls and glass quality.

If ENG is the purpose then neither AF100 nor F3 are ideal as they're specific use is for digital-cinema.

Maybe one day one of the Big Three will give us an ENG camera with film-like DOF characteristics - should you want it - but right now it's an "either - or" proposition, converting the AF100/F3 into an ENG rig can be done technically but not cost-effectively.

I would not group the AF100 and F3 together in this. Sony IS making a couple powered zoom lenses
for the F3, but they will not be released for awhile. They are being made to work with the F3.
Of course the big question, is 'how much will they cost?'

Sony has also made the F3 compatible with Cooke "i Technology" where the camera body communicates directly with their lenses, but all of this stuff - including the upcoming Sony servo zoom lenses - will absolutely be far and away in cost from the budget-minded users of the AF100.

The original point is still valid: If ENG is the intended purpose there are and will be much more cost-effective options for the foreseeable future, especially in the used market.

Something like the interface that Birger may be developing could be the best option if you want a low cost choice. Birger Engineering, Inc. Although, stills zooms often have issues when being used for video.

For a hand holdable ENG style lens designed for these cameras, as pointed out with the adapter, the physical size limitations of such a lens won't give much of DOF difference over a 2/3" camera with a wider aperture zoom.

Robert, just curious, have you some knowledge of what these upcoming Sony servo zoom lenses will
cost? I had not heard anything yet, and as I said, my big question was wondering what they
would cost. Obviously, just the cost of the F3 ITSELF is much above and beyond what a 'budget
minded' person buying the AF100 might want, let alone the extra cost of the Sony lens. But I am
curious as it might fit into a 'mid sized' budget if the lens wasn't too expensive.

Re: Any options for servo?
 

Here's a demo using the B4 adapter.

Demo Footage from Abel’s AF100 ENG Kit | CineTechnica