Blurring All But The Moving Subject?

[Ogrus]

I have a shot where a guy is chasing a dog. How could i blurr all but the guy and the dog (the background i mean obviously)

 

[BLUESPIDER]

You need to create a mask. It will be extremely difficult trying to do this in Premiere. You need a program like After effects. ....

Rotoscope?

 

[Ogrus]

ok, so mask the man and the dog, animate it and then... how does the rest go?

 

[Shooter]

Apply Fast blur or Directional Blur to the appropriate mask area.

 

[Neil Rowe]

you could shoot on a lrage green screen with shorter/fatser cuts to keep the action within the space of being in front of the screen, and then shoot the background with matched camera movement. then composite and add your desired effect to the backgound layer.

otherwise, if you track/move the camera with the subjects at a higher speed on such a device as per say .. a Rowe Cine cine dolly the subjects will be sharply captured albiet their swinging arms/legs, and the background will blur/streak .. all naturally.