Advanced VFX, in class assignments 2 & 3

July 3, 2015 at 7:00 am (School) (, , , , , , , , , )

Next on the docket was to become familiar with more complex scene compositing and utilizing OpenEXR files. The cool thing about .exr files (among other things) is that they can be multilayered. So. You can have 1 file in with all of your render passes (beauty, reflection, refraction, lighting, ambient occlusion, alpha channel, specular highlights, etc.) and each can still be manipulated independently within Nuke. That is so freaking cool. ANYWAY. I had to composite the exr footage of this Robot:

robot

…into a moving pan on this city scene:

city

And for extra giggles, why not add a crashed ship in the parking lot? So, I dropped a hole in the ground, added some rubble and fire, and comped a ship in. Then. I set it on fire. Asset reveal!

Since the shot of the city was actually moving, I had to use motion tracking and the 3D scene elements in NukeX. Cameras and cards and nodes! Oh My! I was pretty proud of this for 3ish hours of work.

The next assignment was pretty similar, but was about simulating a building fire. I’m not going to break it down, because I’m sure you get the idea, but I’ll post the final video. I was pretty happy with the central fire, but not so convinced with the smoke coming out of the right window. If I knew then what I know now, I would just have used particle effects in Maya to custom make all my smoke and fire, but we’ll save that for the next ADV VFX installment.

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Last term, part 1

March 12, 2013 at 6:53 am (School) (, , , , , , , , , , , )

Realized that I never posted anything from last term. LAME.

Nuke. There are always a crap-ton (technical term) of Nuke assignments in a VFX class, rather than a large/term-long project.

Blue screen removal: added noise (aka clouds for the cam to fall through… wheeee!), roto to correct the blue screen removal inadequacies around the legs and cord.

Source assets:

Sky_Dive_Plate

Final video:

Compositing: We got to learn about shuffling & compositing. Basically, you shuffle out different render passes of an image (specularity, shadows, lights, depth, highlights, ambient, etc – there can be a lot). With each shuffled, you can manipulate/adjust each thing independently of the others to maximize the final result.

Original image, pre-shuffle:

original_robot

I added a glow to the lights, but a specific color glow to the robot wires, etc., and used masking to create the glow reflection in the floor; darkened the room and changed the backlighting. I added smoke, because reasons. Post-shuffle composite:

RussellAmanda_wk6

Fake 3D: Take a 2D image of a hallway and fake a 3D camera movement in it. BAM:

MOAR VFX! SO CHEEZY! Hey… lets play spot the fake thing… Ok, so here’s what I did. Took the original video and generated a 3D space using motion trackers to define a ground plane, etc. Once the 3D environment was established, I plonked a spherical primitive into the scene and found a relatively appropriate texture (Why, yes, that is a ridiculously large thermal detonator. Do you have detonator envy? YEAH, YOU DO!), added a shadow. It’s kinda lame, but it was fun in-class exercise and could totally be more awesome with more time to clean up the shadow and color correct… add some snazzy gun fire, etc.

This was our ridiculous final… some doofus decided that in order to make the kid freeze over the pool while the lady walks by, adjusting her suit, they should put a partial green screen behind her for no apparent reason. BTW, this was a real job brought to one of the Ai staff to fix. They wanted to make it cheap. That did not so much work out. FYI… It is MUCH harder and more expensive in human time and effort to remove green screen plus its reflection (aka spill) from people and puddles and metal than it is TO SIMPLY USE THE ROTO TOOL TO CREATE A FREEZE FRAME FOR PART OF YOUR VIDEO. Also… if you are going to use a green screen where the objective is to remove all the green and replace it with something else DON’T HAVE YOUR SUBJECT WEARING AND CARRYING GREEN BECAUSE THAT WILL ALSO BE FIXED ONLY WITH EXTREME TIME AND CARE.

Thus ends the lesson in common sense.

Original cannon ball with freeze frame already completed (water motion reinstated in final video):

Sample of original woman walking by:

Final composite. Painful, le sigh, but got rid of the green junk LIKE A BOSS:

TBC…

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