After Effects to Avidemux - Datamosh Round Trip

This tutorial for shows you how to export video prepared for datamoshing from After Effects, join clips and remove I-frames in Avidemux (freeware) to create the datamosh, then export the result as an image sequence for further processing in After Effects.

Thanks to datamosher on YouTube for his video tutorial on the process.

Nuke Compositing Demo

Here is a walkthrough of a shot I made in the Foundry's Nuke Compositing Software.  Watch it in 1080p if you want to see what's going on in the node tree.

Digital Cinema Package Tutorial

In this tutorial I detail how to create a Digital Cinema Package (DCP) from a quicktime video file.  The source video in this example was HD 1920x1080, 25 frames per second in the ProRes codec.  In order to be sure that the DCP will work on any server I convert it to standard cinema 2K pixels and slow it down to 24 fps.  This demonstration is done on MAC but all operations can be done on PC as well.

DISCLAIMER: SINCE RELEASING THIS POST I HAVE BEEN CONTACTED BY PROFESSIONAL DCP ENCODING LABS POINTING OUT FLAWS IN THE WAY OpenDCP CREATES DCPs.  PLEASE READ DAVID MARGOLIS'S POST IN THE COMMENTS SECTION BELOW AND CONSIDER USING A PROFESSIONAL LAB.

HDRI light probe environment light test in Nuke

LDR still at eV 0

I shot an oversized christmas bauble from each side of my room using Magic Lantern on my 550d to bracket the exposures at -5, -2.5, 0, +2.5 and +5eV. The large exposure steps did introduce some banding when converted to HDRI.  Also, taking the stills with no tripod and not measuring distances resulted in shallow focus and the need to adjust the input rotation in the spherical transform when matching one lightprobe angle to the other in Nuke.  I also realise now that if I took the second set of exposures at a 90° angle form the first rather than 180° then I could have removed myself from the final image.

Three Pass Keying Tutorial

Before and After

After enjoying using KeyLight in Nuke to consolidate an edge matte, a core matte and a garbage matte with one node I decided to see if the same could be done in After Effects.  Unsurprisingly it is not quite as simple in AE but after reading the Foundry's user guide and a blog post from Mark Christiansen as well as watching a light wrap video tutorial by Jerzy Drozda Jr, I have found a workflow which meets my needs.

The footage I am using was captured directly from the EX1 to ProRes4444 using an AJA break out box for Rachel McLean's Scottish Arts Council project.  I now realise that 422 chroma sampling is all we were getting out of the camera but I'm sticking with 444 to avoid a rerender.

After Effects Flow Chart

This tutorial covers the whole three-pass keying process but doesn't discuss the principals of keying or KeyLight in any depth.  For a KeyLight tutorial, check out Andrew Kramer's video here.  A still frame of the footage is available here for anyone wishing to follow along.