I used it quite extensively on a job about a year ago for changing the dialog on an actors face and used it to do a face replacement on a commercial. This was using facetracker and facebuilder. I did load it up about a month ago and had a bit of brain fog on how to use it. But let me know if there is something you want help with and I will do my best to help… Also I believe you are not a Nuke user? They have this plugin for blender so you wouldn’t need to buy nuke. You could do your tracking in blender then export the geo and camera to Flame to do your comp work. I’ve not used the blender version though.
The geo tracker I’ve not used but it’s essentially the same concept as the facetracker.
I used geo tracker for some moving bottle labels. Built a geo, tracked it, projected new labels on the uv mapped geo. Pretty straightforward and better than the Nule internal model builder. But as @kia said, if you get back to it months later definitely need to look back at my notes.
Was considering it as an option for another job I just finished with a motorcycle helmet, which Randy is familiar with.
You can see in the first two rows there is a gradient with values between 0-1. The gamma operation works as you would expect. The highest value does not exceed 1
Once your pixel values go above 1 (rows 3-4) things start to go a bit crazy in the highlights once you apply the gamma. You can see in the lowest graph that the highest value has shot up exponentially to 7.9.
Now in some situations for example where the comps are going to social media the values in the image are getting clipped (h.264) and it’s not going to grade that’s not a problem, however in most circumstance it is an issue. Lets say you are comping in a CG desk lamp into a plate… You whack a gamma correction on it and now the values in the light are brighter than the sun! You might not see this in your viewer in Nuke but pixel values don’t lie. When it goes to grade and the colourist decides to darken the whole image and now you see the desk lamp is nuclear then there is a problem.
Anyway this was a very long winded explanation of why you need to be careful using photoshop blending modes because they are not designed with values above 1 in mind they are designed for 8 bit non float images. Generally most matte painters providing comp with DMPs from photoshop would stick to simple blending modes like over(normal in photoshop speak), add and multiply. It makes the life of the comp artist much easier