I am researching the advantages and/or disadvantages of switching over from shooting with my EX-1 with a DOF adaptor to a 5D or 7D DSLR. From all of the footage I have seen so far shot on these cameras they all have obvious and distinct shutter "jitter'. I for one prefer the natural motion blur that a dedicated video camera produces, especially when shooting progressive. This may be a stupid question, but is there any way of being able to turn the shutter off in the same way you can with a video camera?

The 7D (and 5D) don't use the shutter when shooting video. Whatever effect you see is a result of the way the video is read off the CMOS chip.

I for one prefer the natural motion blur that a dedicated video camera produces, especially when shooting progressive. This may be a stupid question, but is there any way of being able to turn the shutter off in the same way you can with a video camera?
Most of DSLR film makers want the 180 degree shutter for a "film-like" look, but if you want your movies to look more like video, just shoot 30fps with a 1/30th shutter for a 360 degree shutter angle.

We usually shoot 24p with a 1/48 shutter. My understanding is the 7D has 1/50, so I guess that would be "normal" for 24p?

I am researching the advantages and/or disadvantages of switching over from shooting with my EX-1 with a DOF adaptor to a 5D or 7D DSLR. From all of the footage I have seen so far shot on these cameras they all have obvious and distinct shutter "jitter'. I for one prefer the natural motion blur that a dedicated video camera produces, especially when shooting progressive. This may be a stupid question, but is there any way of being able to turn the shutter off in the same way you can with a video camera?

Turning the shutter off on your EX1 doesn't disengage the shutter, it just puts it at the default which on the EX1 is a 360 degree shutter (I think?), hence the motion blur.

A lot of 5D/7D material is shot at very high shutter speeds because people are trying to capture shallow depth of field without using any ND filters. Any normal speed motion shot with a high shutter speed will appear jittery.