C100: C100 pulldown removal

M

mharrison

Member
I have a couple of C100s, and normally record internally. I'm going to start doing some green screen work, and while raw or 4:4:4 would be ideal, I need to make do with the C100s. Externally I can get 4:2:2, so I would like to record to an external recorder. I'd like to use the Blackmagic Video Assist, but it doesn't do pulldown removal (ugh). I know that Atomos and the older Video Devices do, but the slate feature in Blackmagic is really appealing.

Atomos used to make an H2S Connect converter that would do 3:2 pulldown, but they no longer make it...

Q: Do you know of any converters available today that do 3:2 pulldown removal?

Thanks!!
 
mharrison said:
I have a couple of C100s, and normally record internally. I'm going to start doing some green screen work, and while raw or 4:4:4 would be ideal, I need to make do with the C100s. Externally I can get 4:2:2, so I would like to record to an external recorder. I'd like to use the Blackmagic Video Assist, but it doesn't do pulldown removal (ugh). I know that Atomos and the older Video Devices do, but the slate feature in Blackmagic is really appealing.

Atomos used to make an H2S Connect converter that would do 3:2 pulldown, but they no longer make it...

Q: Do you know of any converters available today that do 3:2 pulldown removal?

Thanks!!
Click to expand...

The Atomos ninja 2 came bundled with mine and seems to do the job, at least in 25p
 
Some random green screen thoughts:
I remember reading a post from the SD days that recommended shooting green screen shots vertically to maximise resolution. It obviously depends on the shot, as not all green screen shots lend themselves well to vertical framing. I never tested to see how well it worked, but green screen shots are one of the only situations where I would ever consider shooting vertical video.

I watched a video a little while back that recommended lighting the green screen with RGB lights set to green and putting a minus green gel over the hair light to make pulling a key easier.

I've been too chicken to try much with green screen, but it's interesting to read about the various techniques.
 
Atomos Ninja Blade and Atomos Ninja 2 (like Barry said).

BTW, the Black Magic VM also seems to clip the super-whites randomly (and frequently).
 
drummondb said:
Atomos Ninja Blade and Atomos Ninja 2 (like Barry said).

BTW, the Black Magic VM also seems to clip the super-whites randomly (and frequently).
Click to expand...

This is good to know ... and unfortunate. I was really drawn to the Blackmagic VM for the built-in slate feature, which would help to automate a lot of data wrangling tasks.

I know the Atomos recorders do 3:2 pulldown removal, but they don't seem to have ways to easily add metadata during a shoot.

I might look at the BMPCC for green screen shoots. This would enable shooting BRAW, which should help keying, and also have the slate feature.
That, or a video capture card... It seems that using the C100 + BM VM just wasn't meant to be...

Thanks everyone!
 
Imamacuser said:
Some random green screen thoughts:
I remember reading a post from the SD days that recommended shooting green screen shots vertically to maximise resolution. It obviously depends on the shot, as not all green screen shots lend themselves well to vertical framing. I never tested to see how well it worked, but green screen shots are one of the only situations where I would ever consider shooting vertical video.

I watched a video a little while back that recommended lighting the green screen with RGB lights set to green and putting a minus green gel over the hair light to make pulling a key easier.

I've been too chicken to try much with green screen, but it's interesting to read about the various techniques.
Click to expand...
I've shot a C100 vertically for greenscreen with great results, if a little difficult for monitoring & control. Although you can set this up with creative use of a head, the addition of a tilt plate makes for better control.

Kino makes green tubes for their flo lights. They're awesome for getting pure green on the screen when it's not a head-to-toe green.

I've used some minus green on backlights. More important is just getting good distance between the screen and subject to minimize spill. And lots of back/rim light.
 
mharrison said:
This is good to know ... and unfortunate. I was really drawn to the Blackmagic VM for the built-in slate feature, which would help to automate a lot of data wrangling tasks.

I know the Atomos recorders do 3:2 pulldown removal, but they don't seem to have ways to easily add metadata during a shoot.

I might look at the BMPCC for green screen shoots. This would enable shooting BRAW, which should help keying, and also have the slate feature.
That, or a video capture card... It seems that using the C100 + BM VM just wasn't meant to be...

Thanks everyone!
Click to expand...


If you can get your hand son the H2S Connect it would solve both of those problems. And I assume (hope) that Atomos has a newer product to replace it.
 
I own an Atomos Ninja Blade and it does the pull down I believe? I've used it for almost four years, it's a great device. I don't think the current Atomos products are as good or as well built.
My advice would be pick up a used Ninja Blade or two, problem solved and solved cheaply.

The green screen thing cracks me up, I read so many things about green screen and all of these secret lighting strategies, RGB lighting, special this, special that, MUST have 4:4:4:4 12-bit, etc.
Green screen = lighting. Get the lighting right and you can successfully key almost any camera. I've shot two documentaries that had all green screen based interviews shot all over the
world which is the reason the producers wanted green screen, to provide consisten BG elements. Unlike most green screen projects, we actually shot the BG plates as well, it wasn't stock
or a graphic, they were miniature sets they had built and we photographed them, they looked good but not as good as I could have lit real BGs on location. Both documentaries were shot
on the C100. Not shot vertically, shot horizontally, ran into the Atomos Ninja Blade for an 8-bit to 10-bit 4:2:2 recording and all of the material keyed perfectly.

Not only lighting, but contrast ratio, even lighting coverage, that's just for lighting the screen, then there is the whole ability to match lighting to make green screen scenes photorealistic. It's not
that difficult but it takes prep and execution and shooting plates before the talent OR shooting the talent with at least a clue about how you will light the BGs. Many people who think green screen is difficult
have little to no experience with the latest generation of keyers and compositing tools, they have become better and better with more details and subtlety possible with the key merely by refining parameters.
You can now cleanly key through glasses, blonde wispy hair, all of the things that made green screen a nightmare a decade ago are now MUCH easier and simpler. The tools have evolved for the better.

It makes it slightly easier to have at least 4:2:2 and 10-bit but it's not essential, it's not like you can't pull a good looking green screen even with 8-bit 4:2:0 as most mirrorless cameras shoot. But if you screw
up the lighting, the contrast ratio between BG and foreground, if you don't mitigate green spill, rim lighting for seperation on talent and have enough distance between talent and screen, you can dig yourself a nightmare pretty fast.
 
Green screen is not rocket surgery... The first thing you need is SPACE. I've told producers in the past that this is non-negotiable. If you can't get the subject far enough away from the backdrop, you're wasting your time and money. Don't do it in a space that is too small, just because you "have to"/"don't have a choice" and then just hope for the best when you go to post. I've had to re-shoot other peoples green screen projects, because of this mistake. 2) Light it(green screen) as even as possible. Waveform and false color make this pretty easy to check. 3) Light your subject.
 
Run&Gun said:
Green screen is not rocket surgery... The first thing you need is SPACE. I've told producers in the past that this is non-negotiable. If you can't get the subject far enough away from the backdrop, you're wasting your time and money. Don't do it in a space that is too small, just because you "have to"/"don't have a choice" and then just hope for the best when you go to post. I've had to re-shoot other peoples green screen projects, because of this mistake. 2) Light it(green screen) as even as possible. Waveform and false color make this pretty easy to check. 3) Light your subject.
Click to expand...

Yes, I have been through this too. I don't negotiate with producers on this anymore, no green screen in small conference rooms or in peoples offices. Period. They are setting you up for failure trying to shoot a clean green screen interview in a 10x10 room. I always think of green screen, unlike a regular interview with lighting, which is usually three zones as two zones, the talent zone and the BG zone. Really the two shouldn't affect each other at all, you need that much room, that large of a green screen if they are worried about masking the edges as a lot of my clients are, they don't understand what garbage mattes are, even though the people who are doing the composite do. You have to be careful with a smaller green screen, I have a 4x6 fold up one that's ok for a single talking head but producers have surprised me and added a person at the last minute, like when we arrive on set and a 4x6, flipped horizontally, isn't large enough for a two person interview although I've pulled it off before by cropping arms on either side. For interviews, you really need an 8x8 or 12x12 if you have the room.

Mitigate spill, light the talent right and most importantly, get rid of wrinkles and seams in the green screen and LIGHT IT EVENLY. Every pro camera on the market has zebras, set your sebra to 50-60 IRE and check coverage, make sure you don't have hot spots or holes with not enough light. that's really all there is to it.
The most frustrating is when you ask the producer, "What will be in the BG" and they say, I don't know yet? How are you supposed to light talent? I always end up just doing flat and soft, the most boring lighting because producers like how it makes talent look but quite a few times, I see the final key and they
went with a moody, dramatic BG with a ton of contrast and then there is my flat, softly lit interview pasted over it, so damn frustrating. For some types of shows, it doesn't matter, expecially if you are shooting video news magazine or social media gab fest type things but for some features docs I have shot,
it can be so maddening when I know I could have lit the talent to match the BG lighting perfectly but the producer was lazy and didn't do there homework to decide what the BG will be before shooting. They make you fail as a DP through their laziness and shortsightedness.
 
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puredrifting said:
Yes, I have been through this too. I don't negotiate with producers on this anymore, no green screen in small conference rooms or in peoples offices. Period. They are setting you up for failure trying to shoot a clean green screen interview in a 10x10 room. I always think of green screen, unlike a regular interview with lighting, which is usually three zones as two zones, the talent zone and the BG zone. Really the two shouldn't affect each other at all, you need that much room, that large of a green screen if they are worried about masking the edges as a lot of my clients are, they don't understand what garbage mattes are, even though the people who are doing the composite do. You have to be careful with a smaller green screen, I have a 4x6 fold up one that's ok for a single talking head but producers have surprised me and added a person at the last minute, like when we arrive on set and a 4x6, flipped horizontally, isn't large enough for a two person interview although I've pulled it off before by cropping arms on either side. For interviews, you really need an 8x8 or 12x12 if you have the room.

Mitigate spill, light the talent right and most importantly, get rid of wrinkles and seams in the green screen and LIGHT IT EVENLY. Every pro camera on the market has zebras, set your sebra to 50-60 IRE and check coverage, make sure you don't have hot spots or holes with not enough light. that's really all there is to it.
The most frustrating is when you ask the producer, "What will be in the BG" and they say, I don't know yet? How are you supposed to light talent? I always end up just doing flat and soft, the most boring lighting because producers like how it makes talent look but quite a few times, I see the final key and they
went with a moody, dramatic BG with a ton of contrast and then there is my flat, softly lit interview pasted over it, so damn frustrating. For some types of shows, it doesn't matter, expecially if you are shooting video news magazine or social media gab fest type things but for some features docs I have shot,
it can be so maddening when I know I could have lit the talent to match the BG lighting perfectly but the producer was lazy and didn't do there homework to decide what the BG will be before shooting. They make you fail as a DP through their laziness and shortsightedness.
Click to expand...

Yep. It's a team sport, but so often, I feel like I'm on the OTHER team and the producer is playing against me. It astonishes me, how close some play it to the chest and don't share anything or don't share it to the last possible minute. Some of it is just dumb/lazy, but some I honestly think just do not want to give out details period.

10x10 or 12' seamless paper is about the minimum I want to work with for green screen interviews. I shot a series of green screen interviews for BTS/EPK for a major CGI movie a few years ago and we were doing it at the recording studio(audio) where some of the talent were recording their lines. It was a nightmare. the only space even close to big enough was the presidents office and we had to almost demolish it to make it work and they still had to dirty matte it, because of course, for one of the sets of interviews, it was TWO people.

And as far as lighting a subject for a traditional style interview on a green screen, I'll always err on the side of dramatic. If they don't tell us it needs to match a specific type of "environment", they'll get dramatic.
 
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