Davinci Resolve Nodes?
I'm watching tutorials and see people putting saturation down on one node then cvontrast on another?
What is the purpose of multiple nodes exactly? Couldn't the person just have done saturation and contrast on the same node?
[Manav Bhathal] "What is the purpose of multiple nodes exactly?"
Its mostly organizational, since it is true that you could stack up an entire grade in one node, other than any parallel processes that might be part of the process. Experience shows that sometimes positioning a value within a concatenation will help with controlling it with a downstream process (Secondary corrections seem to work better, for example). But if you want to discipline your approach so that some processes can be shared with other grades, such as adding an overall wash to a clip that has an otherwise unique grey-scale correction, then copying that wash to other clips with their own original values is easier. When working in an interactive session, segregating or isolating corrections within a grade makes it convenient to click it in and out to show what effect is it having. Others specifically design a tree so that it is processed in a pre-defined way... Node #1 does a grey-scale adjustment or other media-specific transform (log conversion, maybe), Node #2 might add some kind of secondary separation or hue adjustment, Nodes #3/4 might be an inside-outside Power Window, Node#5 might be a Noise Reducer or VFX plugin... there might be another node that generates an alpha channel to feed to a transparency separation... split out nodes to process individual channels in RGB or Y'CbCr... it goes on.
Its about flexibility in the end.
"I always pass on free advice -- its never of any use to me" Oscar Wilde.
I totally agree with Joe. I don't always split up functions across multiple nodes, but I do sometimes just in the event the client says "I like part of this correction but not the other part." That way, you can delete one node and give them what they want.
Node organization is a hugely important topic. I tend to do a "normalizing" correction in Node 1 (including camera raw settings if necessary), basic color in Node 2, fine-tuning in 3, followed by windows, keys, curves, and defocus (not always in that order). I typically will do NR last, but it depends on how much I'm leaning on caching. Multiple power windows could easily require 5 or 6 nodes, possibly more.
I have seen colorists that layer 25 or 30 nodes per shot, but I usually have to work fast enough that I'm lucky to hit 9 or 10. For features & episodic TV, I think figuring out how many minutes per shot limits the number of nodes you can practically do in the available time. Commercials are a completely different deal, and if you can spend 4 hours on a :30 second spot, you can certainly spend 15-20 minutes per shot with no problem.
I know reality TV colorists who have to blow through 700-800 shots in a 6-hour session, so they're lucky to do 2 nodes per shot. All you can do is solve basic matching issues and let the subtleties go.
Keeping the node structure identical on every project helps people work faster, since you can figure out where and when to use PowerGrades, drop in Pre/Post-Clip grades, and so on. All the usual tutorials out there deal with this; I think Patrick Inhofer on Mixing Light has devoted several Insights on the subject, and Alexis Van Hurkman has talked about his observations on consistent node structure.