One of the latest effects we’ve been working on is the smoke grenade shot, where our protagonist throws a smoke grenade to distract and divert the Yuriqstani guard’s attention in order to rescue his team mate. We had no grenade prop in the original footage so David just imitated throwing the grenade.
The challenges then faced were to create both a fake grenade in his hand as he tossed it, and of course the actual effect itself of the grenade exploding. After doing some tests with the explosion, we decided to go with a smoke release grenade instead of a fireball explosion or even a standard explosion. Firstly, grenades don’t actually explode in a cloud of fire and heat (even if Hollywood and the computer game industry is set on misleading us), and although we wanted a realistic grenade explosion we just couldn’t get our simulations to look that realistic. So in the end we went for a slow release grenade as we were able to at least simulate that with some accuracy and realistically.
The fake grenade effect being thrown was created by using a grenade model and simply moving it frame by frame in each shot to be in the right place and rotation, then using a mask and lots of motion blur through the Blender compositor to pretty much blur the whole thing so that you can’t see it too closely. The main focus was simply to cover the otherwise empty hand, so it works quite well to that degree.
Put it all together and you end up with this! All effects in this scene are created using Blender 2.75.