This might be a stupid question, but I've done so many google searches that have the terms "depth of field" and "dslr" in them that the only results I get are people trying to achieve the SHALLOW DoF 'film look'.
My question is, is it possible to achieve usable footage with a deep depth of field, with everything in focus?
If so, than why are DSLR's railed against so hard for being poor "run and gun" cameras? Obviously there are a few extra steps involved with audio, both recording and syncing, and maybe the ergonomics aren't suited as well for such a purpose, but if it's possible to get in focus deep depth of field footage with simply a different lens with a higher f-stop, than it's a small price to pay.
I will primarily be using the camera for short documentary/video journalism work.
Use a camera with a 1/3" sensor for "deep depth of field" for Shallow depth of field the APS-C/H; full frame or M4/3 are a better choice. If you only have a DSLR, use a super wide angle lens for "deep depth of field &/or stop down your lens as far as you dare.
Get a set of Expoaperture2 depth of field calculators to plan in advance what stop/lens/format combination works for you. I have not found a manual chart for 1/3" sensors, there must be an on-line version.
If you have a typical shoot, staging from pre dawn to well past sunup for example, at a place like Mono Lake or the Red Desert, the changing light will keep you on your toes.
The use of at least a polarizer, but better still a multi-stop Fader ND, will help keep the visuals static when shooting at the nominal, f8 through f16 etc. or smaller.
Another way to control the changes would be to raise the ISO during the shot (lowest being optimal of course) assuming you will be able to cut around the shift, tripod movement etc. and there is enough light to mitigate noise.
There is absolutely no reason you cannot straddle the concept, by taking say a 24-70 f2.8, and a 70-200 f2.8 along as the shooting package.
The h.264 codec, captures three "slices" per frame, and using quick motion movements like a soccer match may be at issue, but say, tracking water fowl doing a take off, will work fine.
Even as CS5.5 will run h.264 codec natively, editing should be conducted using transcoded footage with high-end products, (cinema grade) such as ProRes for iJOBS machines, and CineForm for both MAC and PC, plus others which essentially converts the IPB slices by losing the P and B, which have computer extrapolated data, and turns the I frames into .444 (laymen description, forgive syntax errors)
The photographer (Ric Kasnoff) is using the 24-70 f2.8 and the 70-200 f2.8, plus a handful of other lenses, when doing this work and all footage is transcoded using ProRes upon download.
Transcoding like that will take a 1 gig file and turn it into a much larger file, so consider that and don't expect to store working files on the boot drive.
Key to any of this is shutter speed (24fps = 1/50 etc.) when changing aperture, ISO and so on but as you suggested managing work arounds, for field work, as long as you have appropriate Fader ND and so on, shooting "long" is really not as issue.
The challenges are not so great, and of course technically, lens diffraction, distortion and so on also can challenge, but as with many efforts, the craft is manageable quite well with patience and planning, and those who are compelled to pixel peep, will not be dissuaded, however, Illegitimi Non Carborundum, as it's been said.