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120fps, 12:1, tungsten, greenscreen...any body had good results?

Eric Rainey

Eric Rainey

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Tomorrow I have to shoot a pigeon on greenscreen. They want it at 120fps, all I have is a tungsten lighted studio they are going to let me use. I did some tests today and the images were very grainy. I have black shaded with body lens cap on...didn't put it in a dark room. I am on Epic build 2.0.5. At 120fps it has to be at 12:1. Should I update the software? It is a small studio and I have the Tokina 11-16. Any thoughts on my setup and if anybody has shot at such high frame rates with compression ratio 12:1 on green screen?

Thanks!
 
Hi Eric

I am guessing that since you are shooting a pigeon at 120 fps, most likely the bird is going to be flying at some point.

One of the big issues with this type of green screen shoot is motion blur of the image against the green screen.

Getting a good key on an image where the wing and the green screen are blurred together can be almost impossible

it is critical to use a very high shutter speed that will minimize the green screen and the wings blurring together,

Get as mush light as you can and shoot a high shutter speed,

Do some test on set and look at the individual frames to make sure the images are clean.

After Effects Keying works amazing with R3D files allowing you to verify a good key on set, I always check the green screen keys this way on location before shooting.

Good Luck
 
Throw a CTB on that tungy or suffer the consequences!
 
Hi Eric

Also wanted to mention that one of the issues RED addressed in firmware release 3.0.7 is "Fixed black shading problems at non-default exposure times"
 
Hi,

If you're shooting as compressed as that I would use an 80A filter properly to boost the blue channel - even at 5:1 I'd still use an 80B or C.

However, at 120fps, you're going to need a lot of light given that the 80A is going to cost you a couple of stops....

Even with the blue channel boosted, I'd still be a little nervous about the level of compression, but if your footage is looking very grainy it sounds like you're probably under-exposed because I've found 12:1 compression to be pretty clean - albeit with fairly simple frames.

Hope that's helpful,

David

www.riverfc.com
 
I have a green hard cyc , permanently lit with 3200 k kino tubes half as far out as the cyc is tall

Hard halo on the bird should help , in my experience , I use primatte Keyer pro. It cleans up really nicely . It also has a spill killer filter.... That's killer .. Sorry had to..
I have no experience with Geen keying at more than 30 fps , so the other gents. Probably know much , that I do not.
 
i have done this exact task and id try to find a happy medium, perhaps 96fps at 9:1 10:1 whatever you can do to bring that down as much as you can...and i found that master primes were the only lenses with acceptable resolution and minimal chromatic abberation. But by all means shoot test and send it to the post people for them to sign off...my post didnt want to wrestle with the possibilty of having to do alot of roto work
 
Just finished a huge post job.. all shot at 12:1 96FPS... A lot of shots were speed up in the edit, But I shot hi speed in case I wanted to slow it all down...
All keyed perfectly.. all shot at 320 asa... All tungsten.
Secret is do not under expose, do not over expose...

If you get a shit key, don't blame the RED files.. blame the monkey thats shooting it or keying it....
I get perfect keys every single time.

here is the link...

[video]http://www.zoomfilmtv.com.au/ftp/Toia_latest/LIN DAN_Li_Ning(BA)_1280.mov[/video]
 
sergio arguello said:
i have done this exact task and id try to find a happy medium, perhaps 96fps at 9:1 10:1 whatever you can do to bring that down as much as you can...and i found that master primes were the only lenses with acceptable resolution and minimal chromatic abberation. But by all means shoot test and send it to the post people for them to sign off...my post didnt want to wrestle with the possibilty of having to do alot of roto work
Click to expand...

If you do not have enough light i like to add a plus one for the happy medium.
 
Thanks a lot guys!!! Huge help! I will shoot at 320 asa, try a prime lens, and upgrade my software to 3.0.7(for the fixed black shading). I might try and gel with an 80a filter as well. Already just changing the iso to 320 in Redcine-X helps a lot with the key. There is a bit of artifacting around the edge of the key but maybe the black shading will help and using a different keyer might help.

Redcine-X question... What "color space" and "gamma space" do you guys use for green screen and best keying?

Nice work on that spot Mark! Looks great!

Thanks again!!!!!
 
Mark Toia said:
If you get a shit key, don't blame the RED files.. blame the monkey thats shooting it or keying it....
I get perfect keys every single time.

here is the link...

[video]http://www.zoomfilmtv.com.au/ftp/Toia_latest/LIN DAN_Li_Ning(BA)_1280.mov[/video]
Click to expand...

Ummmm... not to be too hard on your monkeys, and I wouldn't have said anything if you hadn't held it up for criticism but you didn't get perfect keys in a number of the shots. Well shot spot. But there was a good bit of soft, glowy edges visible even with heavy web compression. "Limited time and money" I know is always the name of the game but some of those might have been caught if the footage was cleaner (or not as the case may be). I'm definitely not saying Alexa or anything else would have given you *better* footage. Shooting 320ISO was definitely the saving grace for shooting tungsten. Also if I frame-by-frame I see that a notable portion of that spot isn't keyed it's rotoscoped (which results in entire limbs disappearing) which suggests to me that they couldn't pull a key and gave up -- deciding roto would be faster.



@Eric. Be kind to your poor monkeys. Give the camera as much light as you can. If you can control the lighting and get your middle gray up to 320ISO--do that. If you can filter the camera as close to 5600 as possible... do that too. Ultimately budget and logistics will win out, but the more photons you can capture the cleaner your keys will be and the less time you'll spend in post trying to 'make it work'. Give the monkeys enough time and they'll paint your entire spot frame by frame to make it look good--but nobody really enjoys that or is happy with that outcome. A $1k in you lighting package can save you $2k in post.
 
Gavin Greenwalt said:
Ummmm... not to be too hard on your monkeys, and I wouldn't have said anything if you hadn't held it up for criticism but you didn't get perfect keys in a number of the shots. Well shot spot. But there was a good bit of soft, glowy edges visible even with heavy web compression. "Limited time and money" I know is always the name of the game but some of those might have been caught if the footage was cleaner (or not as the case may be). I'm definitely not saying Alexa or anything else would have given you *better* footage. Shooting 320ISO was definitely the saving grace for shooting tungsten. Also if I frame-by-frame I see that a notable portion of that spot isn't keyed it's rotoscoped (which results in entire limbs disappearing) which suggests to me that they couldn't pull a key and gave up -- deciding roto would be faster.



@Eric. Be kind to your poor monkeys. Give the camera as much light as you can. If you can control the lighting and get your middle gray up to 320ISO--do that. If you can filter the camera as close to 5600 as possible... do that too. Ultimately budget and logistics will win out, but the more photons you can capture the cleaner your keys will be and the less time you'll spend in post trying to 'make it work'. Give the monkeys enough time and they'll paint your entire spot frame by frame to make it look good--but nobody really enjoys that or is happy with that outcome. A $1k in you lighting package can save you $2k in post.
Click to expand...

To me Mark's works is top notch here. How can you be so sure it is rotoscoped? You can choke mattes in your key-er if you want to "cut limbs" and he already said he shot hi-speed hence higher shutter less blur. I didn't see any missing limbs here just a very good keying job.
 
Robino_J said:
You can choke mattes in your key-er if you want to "cut limbs" and he already said he shot hi-speed hence higher shutter less blur.
Click to expand...

Choking has a very particular look. And also is usually an example of an effort to salvage a bad key. But at least one of the shots is an example of forgetting to animate the roto through the entire shot. So it looks great and then the roto stays put and the limb disappears outside of it. It's a clue that there is more roto in the shot and that was the only one that didn't get finished.

But yeah, good spot. I assume the client was happy and cutting corners controls costs which makes clients even happier. Quick cuts can let you get away with murder. But that doesn't mean there isn't some blood on the frame. ;)
 
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