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alaskacameradude
07-12-2011, 12:41 PM
I've got a shoot coming up that will be talking heads, shot on a greenscreen, and then later I will key them into 'white limbo'. Last time I did greenscreen was with DV and it was a royal pain getting even decent results (I know, DV sucks for greenscreen, but it's what I had.) I am wondering how the AVCHD footage from the FS-100 holds up for keying, I do not have an external recorder yet, and am wondering if anyone has done this yet. It seems to me, that if I shoot at 1080p, the web version (which is where the client wants the final product) should look better as the downrezzing may hide some of the ugly edges. Anyone done any greenscreen shoots with the FS-100 with the built in codec??

ectobuilder
07-12-2011, 03:46 PM
Go with a 4:2:2 8-bit recorder.

AVCHD will fall apart in chroma keying.

I'm assuming that this is a paid job, otherwise you could experiment to see how far you can go with the noiseless gain on the FS100.

alaskacameradude
07-12-2011, 05:10 PM
Go with a 4:2:2 8-bit recorder.

AVCHD will fall apart in chroma keying.

I'm assuming that this is a paid job, otherwise you could experiment to see how far you can go with the noiseless gain on the FS100.

Unfortunately, I don't have time to wait for a recorder to be shipped all the way to Alaska for me to do this project, sounds like it's going to happen this week.
Also, if I did buy a recorder, it would basically eat up most of the money I am charging for this project (its about 3.5k for the whole project). I've keyed with DV
and made it look 'OK' before, I was thinking there was no way AVCHD would be worse than DV. But maybe I'm wrong....

ade4all
07-12-2011, 06:04 PM
check out some of the green screen examples in the pana af100 forum, some very nice keys with avchd, should give you a good idea, it is so much better than dv - sorry cant remember name of threads but shouldnt be hard to find

rejdmast
07-12-2011, 11:43 PM
A lot of it depends on are how good you are at pulling keys and what you are using to pull the keys. I use Keylight and Primatte with Digital Fusion. I have pulled some gorgeous keys with 4K Red Raw footage with Keylight and Fusion but I still needed multiple keys and masks.

If I get a chance I'll try to do a greenscreen shot over the weekend and see how it looks.

PaPa
07-13-2011, 07:25 AM
It will work just fine. Use keylight, do the two layer process, make sure the screen is nicely lit, don't let your backlight get too hot otherwise it will turn your edges purple and avoid excessive movement. I'm getting some nice keys with af100.

bkmvincent
07-13-2011, 04:02 PM
+1 to KeyLight. By far the best of readily available solutions. I did a lot of greenscreen work with XDCAM EX footage (probably hundreds of different set ups, mostly talking heads though) and of all the software/plugins I experimented with, KeyLight yielded the best results; on top of being very fast and easy to manipulate. That is of course you're familiar with AE.

Dermot
07-13-2011, 06:37 PM
+1 to KeyLight. By far the best of readily available solutions. I did a lot of greenscreen work with XDCAM EX footage (probably hundreds of different set ups, mostly talking heads though) and of all the software/plugins I experimented with, KeyLight yielded the best results; on top of being very fast and easy to manipulate. That is of course you're familiar with AE.

Keylight, Primmatte V5, Discreet's Master Keyer, DS's 3D keyer, Nuke's Image Based Keyer.... all good, but if the compression artifacts are larger than the width of hair, then no amount of mess'n with keys is going to help that...

Really depends upon what the target deliverable is.. for the web? take a shot and throw KeyLight at it in AE and walk away happy, for a feature going out to film? take the same shot mess with it for half of forever in Nuke, Flame or DS and it's still a pile of poop... and no one sits on a Flame or a DS unless they already know what they are doing fairly well already.

What defines a good (or good enough) resualt depends upon the deliverables more than the keyer software choice, in any case i would want to start with an uncompressed plate from an external recorder - even if i have to remove pull down first, and i would want to avoid working with 25mbs compression no matter how good the codec is in any case.

Define where the border of "good enough" sits, and define the deliverables, then figure out if the compression will wack you about the head and shoulders (or not).

May not matter, if it does matter, it matters a whole big bunch...

d

bkmvincent
07-13-2011, 07:01 PM
Keylight, Primmatte V5, Discreet's Master Keyer, DS's 3D keyer, Nuke's Image Based Keyer.... all good, but if the compression artifacts are larger than the width of hair, then no amount of mess'n with keys is going to help that...

Really depends upon what the target deliverable is.. for the web? take a shot and throw KeyLight at it in AE and walk away happy, for a feature going out to film? take the same shot mess with it for half of forever in Nuke, Flame or DS and it's still a pile of poop... and no one sits on a Flame or a DS unless they already know what they are doing fairly well already.

What defines a good (or good enough) resualt depends upon the deliverables more than the keyer software choice, in any case i would want to start with an uncompressed plate from an external recorder - even if i have to remove pull down first, and i would want to avoid working with 25mbs compression no matter how good the codec is in any case.

Define where the border of "good enough" sits, and define the deliverables, then figure out if the compression will wack you about the head and shoulders (or not).

May not matter, if it does matter, it matters a whole big bunch...

d

Welp, considering the OP mentioned this is for web, and that he doesn't own an external recorder, the best he can do is work with what he has.

Bottom line: don't expect phenomenal results, but at the very least you can do yourself a favor and work with a plugin that works well in its own right.

aalleexx
07-13-2011, 07:05 PM
[QUOTE=ectobuilder;2387174]

AVCHD will fall apart in chroma keying.

AVCHD will not fall apart when pulling a key, (as long as the green screen is lit the way it supposed to and the talent as well)
I've been doing it for more than a year on over 30 spots for regional and national clients, 422 is better but if you have nothing else then

alaskacameradude
07-13-2011, 07:28 PM
Thanks for
all the info everyone. It is just a informational video. Main delivery is online. Secondary delivery may be to DVD (standard def). I have shot greenscreen with DV before, and I have just about every keying plugin you can think of, Keylight, DVMatte Pro, Key Correct Pro, PHYX Keyer, Primatte Keyer Pro, Ultimatte Advantage.....and so on. I had a contract in the past doing a lot of keying, and was working with DV at the time, so I purchased a whole BUNCH of keying software as it was a decent sized ongoing contract. But then, I haven't done any keying really for the past few years. I was thinking that there was no way that the AVCHD would be as hard as DV to key, even with really careful lighting and using all kinds of plug ins, I was only able to get 'OK' quality at best from DV. Just really blocky around the edges of the key, because of the 4:1:1 color sampling. I smoothed the edges with some of th features built in to the plug ins, and it looked OK. Anyways, I was thinking that the 1080P scaled down, might hide some of the edges and that it would be better to shoot with the FS-100 than to shoot with my old DV camera. The total budget that I am being paid is 3.5K, so obviously not a feature or anything

legrevedotcom
07-14-2011, 12:05 AM
I dont want to derail the thread, I just want to give an example of what can be achieved with a lesser camera like the 5d... the artist shots in this video was entirely done with a 5d, 4 hdmi lights, some green cloth from the local sewing and knittting store and an ambitous post prod guy:

http://www.youtube.com/watch?v=9mLTQ0djEMw

alaskacameradude
08-26-2011, 05:34 PM
So I finished producing this 'info' video. Obviously it is NOT something that I would normally post for people to watch, it is a video for the local PD going through the steps needed to
apply for a job. They didn't want to continue to waste time walking people through the process on the phone or in person, so they hired me to do a video.....pretty boring compared
to what many people on this board are doing, but it helps pay the bills. Anyways, you can get an idea of how the FS-100 stands up to greenscreen work by watching a little of the
video (I wouldn't recommend watching too much as I said, pretty dry stuff!) Keying wise, it seems MUCH better than DV which is what I was using before.....anyways here's the video link:

http://exposureroom.com/members/alaskacameradude/8fc3bfd27798488198dd9a67b5c7373f/

tanega
08-27-2011, 01:15 PM
Wow these are great tips..i have not done Green screen with video yet...but really want to try it now!

Mark Crabtree
08-28-2011, 09:04 AM
If you plan only to key over a white limbo, then green screen is NOT your best option.Shoot with a white limbo background. Light it as you would a green screen. At this point you'll have two choices. Use as is, if the white background you hung was clean enough and just the right brightness, or do a luma key. With the luma key you can replace the background white you shot with a pure graphic white and avoid all artifacts and color fringing that are can be so annoying with chroma keys, especially with 8 bit compressed formats.

alaskacameradude
08-28-2011, 10:35 AM
If you plan only to key over a white limbo, then green screen is NOT your best option.Shoot with a white limbo background. Light it as you would a green screen. At this point you'll have two choices. Use as is, if the white background you hung was clean enough and just the right brightness, or do a luma key. With the luma key you can replace the background white you shot with a pure graphic white and avoid all artifacts and color fringing that are can be so annoying with chroma keys, especially with 8 bit compressed formats.

Ahh....I wasn't aware of that. One question. Wouldn't the luma key also start to get some of the subjects skin tones in it to key out as well? I thought that was one reason to use a blue
or green screen, because they were far away from a person's skin tone.

Postmaster
08-28-2011, 01:07 PM
Okay, here is your options IMHO.

1. Itīs doable if you lit the screen very well.
2. Like someone said, if the artifacts are bigger than a hair - thatīs where it gets um.. hairy.

If you run into a situation like that, convert that critical part to uncompressed and go from there - it may add just enough to solve your problems.

Your other option is - if you have assess to a workstation with video capture card - use that as a recorder.

Good luck, Frank

finaleditor
08-28-2011, 03:09 PM
For a project I got shots from FS-100 with AVCHD, with nano-flash and from Nex VG-10 AVCHD. Nano flash is better but, other ones don't have a problem too. Even for some shots our green screen wasn't evenly lit and had some wrinkles. It is better if you can lit your green screen evenly and one stop less than object. You can use a magenta gel on back light for reducing reflection of green screen on the object. Last year for same kind of project I didn't use magenta gel on backlight and I had some keying problems. Keylight enoug for keying.

Mark Crabtree
08-28-2011, 10:06 PM
Ahh....I wasn't aware of that. One question. Wouldn't the luma key also start to get some of the subjects skin tones in it to key out as well? I thought that was one reason to use a blueor green screen, because they were far away from a person's skin tone. If you light the white background at 100 to 105 on a waveform or zebras set to 100, you will get a good key and have no issues with skin tones. The biggest issue with a key is the edge. The camera will naturally maintain ALL the edge detail between the physical background and the actor, (Fine hair detail, etc.). When you key white over white, any loosely clipped areas around the edge are not noticed because EVERTHING is white. Try it, we do it often and it looks like NO key was done. If you do have any issues with bright skin tones you can easily use a garbage matte. We never need to.

NeedCreative
08-31-2011, 05:02 AM
This is a good thread of tips, thanks guys. I don't use chromakeys much but will refer back when I need to.

legrevedotcom
09-04-2011, 12:04 PM
Small crisis going on here... we did a complete green screen music video with the FS100 and stock lens.

The screen was lit with 3 Kino Flos with green lamps. The talent was lit with two Kino Flo 4ft 4banks and we used 2 lights gelled warm on the back of the talent.

The video is build up so that the main talent goes in a white room and the secondary talents go in a black room. The editor had no problems pulling the key off the main talent to the white room, but he's now looking at the "black" talents and the results he gets when pulling them and placing them in the room is that they get pixilated in the edge. They key will eat part of the talent here and there, and then a couple of secs later it's normal.

I didn't have an immediate answer for the editor regarding this, because I have never experienced it before. What could be causing this? I read somewhere that too hot backlights can cause blockiness, can it be that simple? Did we simply overexpose the backlights?
The screen lights were flagged off and angled away from the talent, so I can't imagine they would cause problems.

The editor said that he had already converted the avchd to prores 4:2:2 to see if that could conjure up some latitude, but to no luck...

So I hope anyone here has some ideas if this can at all be fixed in post with some specific settings in AE (the editor is using KeyLight) or if we have to redo the secondary talent shoot.

Tech data:
1080p
50fps
Iris 8
shutter no less than 1/60
AVCHD to card
on tripod

Scott F
03-08-2012, 08:00 AM
I've been looking through some of the various DVX archives on FS100 and green screen but I have a question or two.

I have an upcoming shoot which will be fairly similar to what alaskacameradude posted with the police video. Most likely waist-up, talent addressing the camera. No movement.

I would like to use the FS100 and kit lens on a studio green screen.

For post, I am planning on using Keylight. My workflow usually involves transcoding to Prores for a FCP edit.

Does anyone have any particular profile settings they can share that they've found work good for keying? (ie, sharpness, black levels, gamma) Or anything I need to watch out for? This is a corporate video project, nothing of cinematic proportions, but I want it to look nice.

From various examples I've seen round the web, it looks like the FS is capable of producing keyable footage if things are done properly.

thanks,
Scott

cheezweezl
03-08-2012, 02:46 PM
Here's a little secret of mine. I do a lot of keying from all sorts of cameras including quite a bit of FS100 AVCHD footage. There is a plugin called "Neat Video". It is primarily used for noise reduction but also cleans up color artifacts. So, in After Effects, apply NV to your footage then apply Keylight second in the chain. If you do a pre-key with color key or similar, do this first then pre-comp the footage, moving attributes to the new comp. Then apply NV and Keylight to the new comp.

Neat Video will cost you a tiny bit of sharpness. It gets worse the noisier the footage is, so if you shoot clean at low gain and expose properly, you won't see much difference, if any. The plugin has a sharpening feature built in to recover any loss of detail.

I was only using it on 5/7D footage and AVCHD, but it really makes all footage look better. It goes beyond the way your edges look. It prevents keylight from degrading other areas not near the edge. There is green in almost everything. Neat helps you keep the green in the areas you want to keep. Try it and look at the difference in your blacks.

plasticam
03-11-2012, 09:29 PM
http://vimeo.com/35381337

This is link to some recent greenscreen on the FS recorded to internal SD card. It was effortless to pull the matte, I sat with editor and it was a snap. He actually remarked on how easily and cleanly it pulled.

Scott F
03-12-2012, 09:55 AM
Thanks for sharing, Caleb.

I can't share my footage, but suffice to say, it came out very similar to what you posted. I'll be dealing with cleaning up some hair & a few artifacts, but for the most part, it was very acceptable.

It goes w/o saying to get a workable key, it helps to have a nice, evenly lit wall. That's half the battle. The studio we used was fantastic.

Dermot
03-12-2012, 10:22 AM
but he's now looking at the "black" talents and the results he gets when pulling them and placing them in the room is that they get pixilated in the edge. They key will eat part of the talent here and there, and then a couple of secs later it's normal.
AVCHD to card
Sounds like it could be compression artifacts that are larger than the object keyed... choking the key and erodeing the edges may be the ugly answer

d

Pastor Thug
03-12-2012, 02:43 PM
Would it be fair to say that keying at 25fps (I'm in PAL land) would be better than keying at 50fps as it works out more data per frame e.g. 24mbps/25 versus 28mbps/50?

kolak
03-12-2012, 03:10 PM
Would it be fair to say that keying at 25fps (I'm in PAL land) would be better than keying at 50fps as it works out more data per frame e.g. 24mbps/25 versus 28mbps/50?

Yes- 28mbit for 50p is quite low compared to 24Mbit for 25p.
Use external recorder to capture 4:2:2.
All prosumer formats (AVCHD, XDCAM EX/HD) are heavily compressed- use at least 100Mbit MPEG2 I frame, or AVC-I. Latest one is on the edge of high quality capture formats, but with specific content can also struggle.
ProRes, DNxHD recorders are cheap these days and they offer way better quality, so if you can use it :)

You can even get one of BlackMagic recorders (they are so cheap) and record to laptop over USB 3.0 or Thunderbolt on MAC. This is possible specially for studio work.