Achieving shallow depth of field
 

Coming from an ENG/Sports background I have had no experience with 35mm Prime lenses. I understand how to gain shallow DOF with a zoom lens, but is it possible to achieve the types of shots that Tom Guilmette (www.vimeo.com/868799) and Phillip Bloom et al get on their films by using the EX1 without a Letus and primes? Alternatively can I achieve the same looks in post?

The short answer is: No.

However, the EX1 has a shallower depth of field than most camera's in it's pricerange, but nowhere near what you can achieve with a 35mm adapter. The same will hold true for the EX3.

In post you can use blurring and vignetting effects to selectively 'focus in' on parts of your footage and create an effect that may look similar to DOF, but this lacks the finesse and control you have over the DOF when shooting.

You don't need to use primes with a 35mm adapter, any lens will do. Primes however can be faster and are more common in (film) production, which is what you try to emulate.

George/

Play with the filter
 

George is right but u can change your shallow depth of field playing with the ND filter and gain (in certain light conditions) :

As Bruno points out, using a bigger aperture results in shallower/shorter DOF. So does using larger focal length lenses, although the result looks quite different between wide and tele lenses.

George/

The excellent trick of these adapters is NOT that they allow attachment of an alternate lens, but that they effectively change the "film size" in the DOF equation. The add on lens is positioned to produce its image on the adaptor's large ground glass, not the sensor. The attached lens is focused on that ground glass image. Thus you achieve the DOF from the larger "image". The same lens can not produce the same result directly to the smaller sensor. Clever.

You can also achieve more of the shallow depth of field "effect" by moving your subject farther away from the background. For instance, in Bruno's shot above, if he had moved his subject farther away from the background foliage but kept his zoom out and the iris open (using ND filters), he would have blown the background out of focus even more.