-
Anyone care to show their skills at sky replacement? NEED HELP!
Hey guys,
So I’ve got this short clip, and I need to make the sky transparent in order to replace it with some cool time lapsed thunder cloud footage I have. I’ve tried some different techniques, some worked better than others, but with all of them I would have had to mask the subject and keyframe the path to match his movements which I’m trying to avoid as much as possible.
So I’ve got a screenshot of the clip, https://i11.photobucket.com/albums/a165/Bjomesphat/Sequence01.jpg if you want to check that out. And I’ve also uploaded the clip to Yousendit so if anyone wants to download it and try it out I would greatly appreciate it. If you are successful in removing the sky without a lot of masks involved, I would like to hear the technique you used or would like the project file (I have CS3) so I can see myself. Or if anyone just wants to comment on how they’ve done sky replacement in the past or know of any tips, that would be very helpful too.
Thanks a lot! Here is my clip: https://rcpt.yousendit.com/681530036/c8b1657ad1c5be346a43a47b8d859ad3
By the way, the clip is exported in Quicktime Photo-JPEG at 95% quality, and at 1440×1080 (1.333 aspect ratio) at 23.976fps.
-
3 Replies
-
Didn’t have much to do today, so I took a quick shot at it.
Drag 3 copies of clip into timeline. Apply leave color to both layers.
On the top layer select a green from the grass.
Amount to decolor = 100%
Color to leave = 10%
tolerance = 20%Middle layer-select orange from shirt.
Amount to decolor = 100%
Color to leave = 15%
tolerance = 20%Set top layer to overlay. Precomp top two layers. Add “set matte” effect and use blue channel as matte and then invert matte. Add levels effect, and switch to alpha. I set imput black to 69, and imput white to 152.
Now use the precomp as a alpha matte. Still some masking involved, but a whole lot less. I didn’t spend a ton of time selecting the colors to for the “leave color” effect or playing with the tolerances—so if you play around you may get some better results, but, you’ll have removed almost all of the sky this way.
Johnny Cuevas, Editor
http://www.ckandco.net -
I know that Andrew Kramer at videocopilot.net has a really good tutorial on sky replacement techniques.
Tutorial number 1 involves basic tehniques, but there is also tutorial number 42 for the advanced techniques.
You should take a look i think it may help you a lot
Daniel Capener
-
Thanks guys.
I initially tried Andrew Kramers technique and got ok results, and thanks John for your technique as that seems to have a little more versatility, but in the end it seems like I’m going to have to do the same masking for each.
Reply to this Discussion! Login or Sign Up