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Recent Comments
- pralhad on Colour Smear for Nuke (UPDATE v2.0):
i use this node education parpose - Francois Leduc on FrameBlendMerge:
You could also use a TimeEcho node. There’s no Min mode, but to fix that, apply a Invert Node to your source, plug TimeEcho (in Max method) and apply another Invert node after. Go at the end of your timeline, change the “Frames to look at” to the number of frames or your shot (or less) and you should get your clean plate. Of course all of this is done on a stabilized shot. - Richard Frazer on Colour Smear for Nuke (UPDATE v2.0):
Hi Josh. Thanks for the feedback. You have correctly discovered that this tool works best when you have a solid core for a matte with a feathered edge. Where it fails is if you have large areas that just have semi transparent alpha (such as your grimy window). I’d approach this by separating your actor with a rough roto and using the colour smear to deal with their edges. Then for the smudges maybe try extracting the green channel and using using it to drive a grade for your background, or... - Josh Northeast on Colour Smear for Nuke (UPDATE v2.0):
Hey Richard! Absolutely love the tool. Saved my ass alot. I’m working with some greenscreen plates where there is a smudgy window behind the actor and a greenscreen behind that. We need to preserve the smudges on the window but that means it’s hard to use your tool to treat the edges because the alpha isn’t clean. Any tips? Cheers, Josh - Matt on Keyframe Reduction script for Nuke:
Nice! Just used this on a projection/stabilization job and it worked great to simplify the original camera keyframes and smooth out the reprojected shot. Thanks!
- pralhad on Colour Smear for Nuke (UPDATE v2.0):
CameraSmooth for Nuke
January 17, 2016
THE PROBLEM
For a recent project I had a long steadicam shot that had picked up some high frequency jittering that needed to be removed. Its a problem that the smoothCam tool in Shake / Final Cut was made for, but I needed a solution that worked in Nuke.
There was already a 3D camera that had been tracked by our matchmove department, so I wanted to create something that utilised the virtual camera, rather then using optical flow or some other heavy process. It also needed to be non-destructive to the original camera track – i.e. I should be able to adjust settings to smooth the tracking, but leave the original data intact.
THE SOLUTION
The solution is straight forward. I create a 3D card that travels at a fixed distance in front of our original camera. The camera projects the input footage onto the card. I then duplicate our original camera and apply a smoothing filter to its values – this uses the “integrate” python expression, and there is a great Nukepedia article by Frank Reuter that explains the process. We then render out the card using a ScanlineRender that is connected to our smoothed camera.
THE NUKE NODE
I wrapped this up in a group that has two inputs – the footage to be smoothed and the 3D camera. I created separate knobs for smoothing the translation and rotation of the camera, as one may need to be smoothed more than the other.
Here is the GitHub link for the node – just select the text, copy it then, then paste it into Nuke.
ADDITIONAL CONSIDERATIONS
If you do not have a tracked camera there is always the Furnace F_Steadiness node available in NukeX, which is similar to smoothCam. However, it uses Global Motion Estimation which is processor intensive.
5 Responses to "CameraSmooth for Nuke"
admin says: January 22, 2016 at 5:35 pm
Hi Francesco
Thanks for the feedback. These are all good points and I’ve updated the gizmo with these new features
Cheers
Johannes says: February 11, 2016 at 12:09 pm
Hi Richard, thanks a lot for the great tool!
Just realised when using it on circular pan, that it gets freaked out by the sudden jump in value when a camera’s rotation goes from +180 to -180. Maybe there’s a way to fix that? Cheers!
admin says: February 11, 2016 at 12:27 pm
This starts to get into a world of mathematical pain that I don’t want to go near at the moment. If there is no reason why you would need to constrain all values to be within a 360 degree range, then I would simply select your keys after the ‘jump’ in the Curve Editor, select Edit > Move from the right-click menu and then add +360 (or -360) to the ‘y’ value so that the animation curve continues in a smooth line rather then jumping a full rotation. You can then apply the smoothing filter without any problems.
Johannes says: February 17, 2016 at 5:42 pm
Will do, thanks!
Hi Richard, thank you for sharing!
Played a bit with the GitHub version of the Gizmo, noticed something is broken> the card is linked to Camera5 instead of being linked to the input cam. I would like to make a few suggestions> right now to see the smooth effect over the original curve we have to expose each camera\s parameters. It would be nice to have input and output valueS in the interface, so they are easily accessible. It would be also nice to have different smoothing controls separately for XYZ (using a color input instead of a floating point slider will do). Cheers!