I worked on Hercules in 2013 as a VFX Texture Artist. Here I wanted to show some detailed breakdowns of the texture process and work I did for this film. The task for the show was creating digi doubles and props that they would hold or use. Mainly I will talk about Mari texture work flow and tips.
Digi Double Autolycus-
Here is a render I did showing the character Autolycus with final textures and some nice lighting an Arnold.
For this job, and I think most big productions right now we used The Foundry's Mari for texture paint work. It is a really nice program to work with and allows many high resolution maps for an object, not really possible in Photoshop. For this character we used 20 4k UDIMS (individual texture files).
One big tip I would give with Mari is always archive your file when you have done half a days work, due to the unique way Mari saves files you cant 'save as' numbered versions so their is a chance of losing all your work if Mari directory becomes corrupt, it has happened to me and others, and is not fun. So learn from our mistakes :) Its funny the company gave me feedback on this character which was to paint in veins in hand and arm, and make finger nails dirty, but after viewing the film the whole hand was about 10 pixels. I find this over building of assets extremely common in the VFX industry. Yes you want the work to look as good as possible, but you need to plan and know at least roughly where and what scale assets are being used, to avoid wasting time over building, I find this is where most companies fail and waste resources.
Hercules club
Hercules club for the digi double was a cool asset to work on. I started by grading my reference using a macbeth chart in nuke and then going into Maya to create camera lineups for around 8 images around the asset. I find it better to spend the time to get at least a rough line up in Maya and then export those cameras out to Mari for projection. When you export cameras out you should use .fbx, and if you ever get a camera in Mari and it does not match exactly what you see in Maya you need to freeze the transforms on the camera and export again. It took me a while to figure that one out. Another sneaky Mari thing that can cause issues when projecting, is your image does not projected in the exact same aspect ratio as you would expect. If you go into Projectors > transformation the default setting for scale is 1.5 by 1, if your image is not in this ratio you should change this setting. So if I have an image that is 4,000 x 3,000 pixels I divide those numbers to get a ratio 0f 1.33 by 1. I hope those 2 tips can be useful for someone as it as cost by a lot of time to figure that out :)
Atalanta Bow, Arrow holder, Army shields
A few other noteworthy assets that I worked on above.
A couple of final Textureing/Mari tips I picked up on this project:
If your working in a linear pipeline (especially working with dark images) its a good idea to convert the images to .exr in nuke before you bring them into Mari or you can see some bad pixellation at the lower end of the black scale, also in preferences > GPU > Virtual texture size, if this is set to Byte this can also cause some pixellation of darker images. Before you export your image out of Mari add a clamp (Channel > Add adjustment Layer > clamp) this prevents Mari from exporting texture maps with dead pixels or pixels with extreme values. Finally if your ever working with projection images that look brighter and more blown out in Mari than they are in Nuke try going to Painting tab and under Paint Buffer switch off 'clamp'.
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