please help with key in keylight
by Derrick van Niekerk
on
Aug 8, 2008 at 8:08:28 am
Hi there,
I've got footage with a green sceen that wasn't lit the best, I would like to say a friend gave the footage, but that would be a lie. I shot that, i know, i know.
Could someone please help me with keylight 1.2 settings to get the best possible result, I understand garbage in, garbage out, but I'm sure someone could help me make the best of this?
Reshooting is not an option, and it does not have to be 100% perfect, I've played around for two nights now, and my results suck.
Re: please help with key in keylight by Pat Jaeger on Aug 8, 2008 at 3:45:51 pm
Hey,
Im not sure about the settings as I havnt tested with your footage yet but you may get a better key if you make a tighter junk matte.
Have a look at Aharon Rabinowitz's 'super tight junk matte' tutorial:
Re: please help with key in keylight by Dave LaRonde on Aug 8, 2008 at 3:47:35 pm
Sorry to have to say this, but in my opinion that's a shot not even worth rescuing. Its only remaining value is as a bitter object lesson in planning an effects shot properly.
Are you familiar with the term "rotoscoping"?
There are so many things wrong with this shot I wouldn't even know where to begin fixing it. I'll let the less-realistic folks around here offer up their difficult-to-do and time-consuming suggestions.
Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Re: please help with key in keylight by Kevin Camp on Aug 8, 2008 at 3:48:30 pm
if you haven't already, go to the tutorials page and search for super tight junk mattes for a tutorial done by aharon rabinowitz. he shows a very useful technique for creating very accurate junk mattes which should help you out a lot here.
also, in the keylight manual, there is a technique they describe for using their 'inside mask' feature... it's around page 42 in the pdf i have.
basically, aharon's technique 'crops out' much of the information that you don't want to keep (the area out side the subject edges) and the inside mask technique is used to define the area you definately want to keep (the area within the subject edges), leaving you with just he area around the edges to focus on. it's not a one step process, but it is usually quite effective.
if you are comfortable with aharon's super tight junk mattes method, you can actually copy and paste those masks onto you footage, use mask expansion settings to shrink the mask inwards and use that for the inside mask (it will render much faster than than 2 instances of keylight, as the pdf describes). note, this can get a bit tricky if you have multiple masks from auto trace.
Re: please help with key in keylight by Robert Houghton on Aug 8, 2008 at 5:17:35 pm
I was able to get a decent key using AE's native Color Range keyer. Keylight is a good tool but it is definitely not a one-click wonder. On a recent project we were forced to abandon it just because it tried to do too much.
The first one has basic curves and levels adjustments, and the second has 2 foreground layers and basic colour correction too - I used one of the sample pics that comes with Windows for the background, but I guess it depends on what background you want to use.
It also depends on what format you are ultimately rendering out to, whether it's intended for broadcast or not.
But for 20 mins work, for a personal project I would say this is reasonably acceptable!
If you agree, and are happy with the result here, please do not hesitate to reply to this and I'll see what I can do.
If it's NOT acceptable, then I apologise for wasting everyone's time - this is my first post on here, so I hope I haven't upset anyone by doing this! But I hope that I've been able to help in some way... :-)
Re: please help with key in keylight by Derrick van Niekerk on Aug 8, 2008 at 9:00:09 pm
thanks for the replies,
Dave, your right, it is a lesson in taking more time or rather moving a little shoot to another day, we wanted to get done, and that is why we have the poor result.
It is a personal project for a friend, I would like to try and use this, even though I know the truth, it needs proper reshoot, but to get those two together in daytime is almost impossible.
Nick, I would like to see those images, but when I click the links the webpages are empty?
any chance you could maybe post the AE project file please?
'course, it needs some holdout on the belt, and trim on the bottom. Pretty scrappy, but if you're also trying to get a handle on where your mad-skillz collide with your footage quality, this may help you have some perspective. One of the frustrating things when I was learning to key was not knowing where the problem was. Go through the Keylight manual/tutorial. It's not an effect you can just play with until you understand it. There's a method.
This was done with a bit of Curves, then Keylight, then some Hue/Sat (to kill the green), then a bit of Color Balance to whiten the highlights a bit.
Re: please help with key in keylight by Patricio Veloso on Aug 8, 2008 at 9:38:21 pm
Its not a very expensive plug-in and we use it in real world professional productions.
Currently im working as freelance compositor in a post facility called www.daf.cl and sorry for my english but i dont understand what you mean with cross-grade.
Patricio Veloso
Broadcast Editor / Postproducer / HD Addict!
Greetings from Chile.
Re: please help with key in keylight by Brian Lynn on Aug 10, 2008 at 2:54:31 am
For those who don't know what a "cross-grade" is:
A cross-grade can be several things, but mostly its the ability to move one piece of software from one operating system to another.
For example (this is not real):
You own PicturePerfect PRO v.1
Its on a Mac.
Your Mac died, and now you own a PC.
Instead of having to pay for a full liscence again a lot of companies will "cross-grade" you, allowing you to move your software from one Operating System to another, for a reduced price. Many will do it for free!
Another type of cross-grade is when you own a piece of software, but you want to switch to another software...
For example (again, not real that I know of):
You own Combustion.
You now like After Effects better.
Adobe gives you a "cross-grade" discount on an After Effects liscence to bing you into their house of tools, and away from AutoDesk.
Or:
You own Cinema4D.
You now need the power of Maya.
Autodesk offers you, as a user of Cinema4D, a discount for Maya to get you into their house of tools.
Re: please help with key in keylight by Greg Neumayer on Aug 10, 2008 at 10:16:43 pm
Thanks Danny. That wasn't new to me, but I'm sure it's helpful.
However, I was just (a little off-topic, admittedly) trying to decipher this specific cross-grade offer from Red Giant. It gives the price, but I can't find the qualifying requirements.
Re: please help with key in keylight by Brendan Coots on Aug 9, 2008 at 7:01:56 am
Two people so far have said to color correct your footage before keying, but this is actually a bad idea (sorry!).
Keylight is a color difference keyer, meaning it compares your chosen "key" color to the color of every pixel in your image. if a pixel's color is too "different" (determined by your threshold settings) then it is not keyed.
Since color correction affects all pixels equally (for the most part), the relationship between key color and everything else is exactly the same as before, so there is no actual, mathematical benefit to the end result. Actually, by color correcting first you will degrade your image (all color correction tools degrade footage to a degree) so the keyer is a little less likely to do a good job.
Also, the notion of blurring your background isn't a plausible solution. A good key is all about the edge of your actor. If you were able to mask out the actor so the blur only affected the background, and very cleanly came right up to the actor's edge, then you'd be on to something. But, at that point, you'd have a great roto so why bother keying at all?
Re: please help with key in keylight by Pat Jaeger on Aug 9, 2008 at 8:11:35 am
You can apply a blur to the edge only by creating a new adjustment layer with a Gaussian blur of 4. Then set the transfer mode to colour and you have a slightly softened edge before the key. Ive used this method countless times on DV footage and its allowed me to get a much cleaner edge than without it.
Re: please help with key in keylight by Derrick van Niekerk on Aug 8, 2008 at 9:14:38 pm
I just watched the super tight junk matte tutorial, and it should help a bit.
i'll also read the keylight manual, haven't read it in a longtime,
i know I'm trying to get blood out of a stone here, I'll never take a greenscreen shoot so casual that's for sure, but maybe a can get acceptable result, Greg's looks workable.
when applying levels, do you boost the green to try and get a more even screen?
Re: please help with key in keylight by Nick Tregenza on Aug 8, 2008 at 10:56:35 pm
Hi Derrick,
Sorry about the earlier mishap with the weblinks...if you are able to e-mail me on trig_fx@hotmail.co.uk, I'll be happy to send you the project files if you think it will help.
Shame the links didn't work on here - seems I have a few things to learn about posting links!
But all the info everyone has provided on here so far is pretty much it. I've been keying footage for over 2 years and I guess there's a knack to it: I just soaked up EVERYTHING I could find - and not just on this site: Brian Maffitt's tutorials on Total Training were invaluable too...
I tried everything and used what works best for me. I guess everyone has their own way of doing things - there's no ONE correct way of doing things which is what makes visual FX so challenging and exciting! :-)
Re: please help with key in keylight by Danny Hays on Aug 10, 2008 at 10:04:28 pm
Keylight is a great keyer but with a poor lit green screen, Ultra is far better. If your using CS3 Premium. I believe it comes with it. It can key out even the worst lit screens. Danny Hays
Re: please help with key in keylight by solie swan on Aug 11, 2008 at 3:14:31 am
Couple of things:
1. Start by duping your footage and pulling an inside and edge key and combine the footage
2. If that does not work, do the same but break it up into smaller chunks - split the people into different comps, key the hair seperate from the body etc. Trying to do this with one key will lead to frustration.
