Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

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MochoCinematic

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Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostThu May 12, 2022 1:51 pm

As the title says, I have both Pocket 6K and the Ursa 4.6K G2.

Which one should I use for green Screen work? I don't have enough time to test both unfortunately.

There will be a lot of creative lighting in the characters. Which one should perform better?

I know that the pocket as less noise and dual ISO which should be a win?
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostThu May 12, 2022 2:19 pm

MochoCinematic wrote:As the title says, I have both Pocket 6K and the Ursa 4.6K G2.

Which one should I use for green Screen work? I don't have enough time to test both unfortunately.

There will be a lot of creative lighting in the characters. Which one should perform better?

I know that the pocket as less noise and dual ISO which should be a win?

Although it is true that the pocket with the dual ISO, when set correctly, can have less noise, the G2 has other sensor characteristics and more DR for that matter. Both cameras would be fine for green screen work using a less compressed codec like BRAW Q0 and at the highest resolutions (6K on the Pocket and 4.6K on the G2). Having said that, the more important thing is to properly and evenly lit the green screen and the characters especially on your case you said there are a lot of creative lighting to the characters. Avoiding any color lighting spill on to the green screen and an even luminance (evenly lit) on the green screen is critical. If you have addressed the latter, either camera should work just fine and becomes a matter of preference.
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Jamie LeJeune

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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostThu May 12, 2022 2:49 pm

It's an interesting question which of the two would yield the best key.

Whichever camera you go with, noise is the enemy of clean edges, so I would rate the camera one stop under the "base" iSO to keep the noise at a minimum — meaning exposing for 400ISO on the G2 and for 200ISO on the 6K Pocket Pro. The difference in base ISO alone may help make the choice depending on your lighting setup.
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John Brawley

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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostThu May 12, 2022 5:25 pm

MochoCinematic wrote:As the title says, I have both Pocket 6K and the Ursa 4.6K G2.

Which one should I use for green Screen work? I don't have enough time to test both unfortunately.

There will be a lot of creative lighting in the characters. Which one should perform better?

I know that the pocket as less noise and dual ISO which should be a win?


What Codec are you shooting ?

If it's ProRes, then the G2 can do 444 12 bit ProRes. The 6K is "only" 422 which would not be as great for green screen work.

If it's BRAW, then it's a closer call.

In my view the G2 would be better, mostly because it has a MUCH faster rolling shutter time, something that's always making VFX shot credibility more difficult, mostly because it makes any object tracking and lens geometry harder to track.

JB
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostThu May 12, 2022 5:52 pm

What about Pocket 4k rollback to older firmware that can shoot cDNG?
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostThu May 12, 2022 6:09 pm

Many believe CDNG is better than BRAW.

I don't think it makes much difference in this scenario. I'd still think the faster RS of the G2 BRAW trumps any perceptual difference with C-DNG. (and for me probably the slight edge in DR too)

I've been a party to a lot of engineering samples and testing....

Most of what's perceived to be sharper just isn't. It's "false" sharpness because of the lack of OLPF. You're devoting all this extra data to recording marginal information.

And that's only if you shoot uncompressed.

As soon as you also shoot CDNG compressed, then it's a wash. BRAW is better in every way, from playback to end result.

JB
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Jamie LeJeune

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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostThu May 12, 2022 10:53 pm

John Brawley wrote: Most of what's perceived to be sharper just isn't. It's "false" sharpness because of the lack of OLPF. You're devoting all this extra data to recording marginal information.
+1 to this. While I'm no VFX expert, as a working colorist I can say that the supposed extra detail in cDNG is virtually all false detail that is riddled with color moiré. I'll take BRAW over cDNG every time.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostFri May 13, 2022 12:25 am

I'm just going to put this here for now because he used a UMPG2:

"I'm well trained in the art of turning **** to gold." - Tim Buttner (timbutt2)

Cameras: URSA Mini Pro G2 & Pocket 6K Pro
Past: UM4.6K, P6K, BMCC 2.5K
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostFri May 13, 2022 12:27 am

timbutt2 wrote:I'm just going to put this here for now because he used a UMPG2:


Ideas are brewing off this for a new camera pitch. A Blackmagic Virtual Production Camera! More to come later.
"I'm well trained in the art of turning **** to gold." - Tim Buttner (timbutt2)

Cameras: URSA Mini Pro G2 & Pocket 6K Pro
Past: UM4.6K, P6K, BMCC 2.5K
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostFri May 13, 2022 5:22 pm

+1 to braw, I did comparison with umpg1 shooting both codec same situation.
Cdng give you false dectails that sometimes can give you too much edge enhancing that you shout avoid.
Braw 3:1 or Q0 give you a great quality to cleanup green without problems.
Some suggestions:
- subject far away from green screen to avoid reflection and more
- avoid to exaggerate to light green screen or you risk to see reflected light on skin and cloth, see in the movie often green is dim than tv show or news
- not put green on floor but add elements like where you put (to avoid reflection and give to dress the right light)


Inviato dal mio iPhone utilizzando Tapatalk
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 1:02 pm

John Brawley wrote:
MochoCinematic wrote:As the title says, I have both Pocket 6K and the Ursa 4.6K G2.

Which one should I use for green Screen work? I don't have enough time to test both unfortunately.

There will be a lot of creative lighting in the characters. Which one should perform better?

I know that the pocket as less noise and dual ISO which should be a win?


What Codec are you shooting ?

If it's ProRes, then the G2 can do 444 12 bit ProRes. The 6K is "only" 422 which would not be as great for green screen work.

If it's BRAW, then it's a closer call.

In my view the G2 would be better, mostly because it has a MUCH faster rolling shutter time, something that's always making VFX shot credibility more difficult, mostly because it makes any object tracking and lens geometry harder to track.

JB


I filmed Raw and went with the pocket. I did some test just before but the keys come terrible in the end with both. I always have to convert the mate using a bitmap and use that as a mask otherwise there is loads of weird artifacts with the deltakeyer.
I used to have a canon C300 MKii and the results were really good but for some reason with blackmagic it's always a nightmare.

And yes I did light up enough, I had enough separation from the background.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 1:08 pm

As I replied to someone.
For some reason I can't get good keys with the blackmagic cameras.
The end product keyed ok but it's always a nightmare, lot's of artifact etc.
Some test shot's keyed horribly with the Ursa. My note 10 phone does better with filmic pro.

My Old C300 would pull keys incredibly.
I added enough light and enough separation. Yet it always turns bad.

I'll try to upload some examples.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 1:13 pm

Are you able to share some shots as BRAW ?

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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 1:27 pm

John Brawley wrote:Are you able to share some shots as BRAW ?

JB


I'll try to upload. I'll upload a good one from the actual shoot (they turned out better)
A ursa one that turned really bad with the same exact settings as the pocket.
and a C 300 (previously shoot) The edges look far better with simple key.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 4:36 pm

MochoCinematic wrote: For some reason I can't get good keys with the blackmagic cameras.
The end product keyed ok but it's always a nightmare, lot's of artifact etc.
Some test shot's keyed horribly with the Ursa. My note 10 phone does better with filmic pro.
My Old C300 would pull keys incredibly.
There is some error here not inherent to the camera. I’ve keyed every one of the BRAW shooting BMD cameras without any problem. The 422 codec from the C300 results in far more chroma issues on fine edges than any BMD camera recording BRAW.
At what ISO are you exposing and what transform to REC709 is being used?
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 5:33 pm

Jamie LeJeune wrote:
MochoCinematic wrote: For some reason I can't get good keys with the blackmagic cameras.
The end product keyed ok but it's always a nightmare, lot's of artifact etc.
Some test shot's keyed horribly with the Ursa. My note 10 phone does better with filmic pro.
My Old C300 would pull keys incredibly.
There is some error here not inherent to the camera. I’ve keyed every one of the BRAW shooting BMD cameras without any problem. The 422 codec from the C300 results in far more chroma issues on fine edges than any BMD camera recording BRAW.
At what ISO are you exposing and what transform to REC709 is being used?


I am definitely doing something wrong.

I filmed Raw 5:1, I tried 444, 5:1, Q0, and Q5.
The results are always the same. I tried with various settings. I am uploading ones at 5:1.
I film in Film mode everything.

Another thing I noticed is that all the LUT I try in camera look terrible. When I apply the option to use LUT in Resolve it gives the same effect.

ISO I did 200, 400, 800 on the URSA. For the pocket I did test at 200, 400, 800, then 1250 at dual ISO.
There was not much difference in noise from 400 to 1250 so in the end I filmed at 1250 (I know it's high but worked well and allowed for high shutter angle for less blur and aperture at 4.0)
The keys with ISO at 400 weren't any better then the 1250.

I can't share most of the files because of the people I used don't feel comfortable with me sharing but I managed 1 shot of each camera.
The hair is the biggest issue, the edges look all weird.

I honestly appreciate any input on what's getting done wrong. I composited so many shots with hair detail. It's the first time I am encountering these issues.

So, to simplify. The problem I have is.
Getting the edges and hair to look good and detailed.

Keying in delta keyer the colour go all crazy and becomes blocky. ( I shoot material to use in some courses I run, I need to be able to pull a key easily like the C300 shot. No Fuss, no need to create bitmaps etc as that's to complicate to introductions in the course)

Keeps in mind that I can get decent keys, it's just with 4 times more steps. and sometimes the hair looks bad. (not the case in the shot I am sharing, not as terrible)
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 5:34 pm

Some shots here

https://drive.google.com/drive/folders/ ... sp=sharing

The worst ones I can't share due to who is on camera, so hard to show the worst.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 9:17 pm

I’m away from the computer. Will download and take a look at the shots later today.

In the meantime, I think the issue is the LUT being used. Rather than using any LUT, simply set the BRAW decode to Gen5 BMD Video and then pull the key.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 9:44 pm

Jamie LeJeune wrote:I’m away from the computer. Will download and take a look at the shots later today.

In the meantime, I think the issue is the LUT being used. Rather than using any LUT, simply set the BRAW decode to Gen5 BMD Video and then pull the key.


That's what I did.
The LUT is for reference when I am filming but I never been able to actually use it as they look appalling in both cameras.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 9:48 pm

Um ... that's a red flag right there.

Describe "appalling" please. On my BMPCC4K they are pretty useful if I have exposure/gain(ISO) settings correct foe the scene.

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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 10:07 pm

rNeil H wrote:Um ... that's a red flag right there.

Describe "appalling" please. On my BMPCC4K they are pretty useful if I have exposure/gain(ISO) settings correct foe the scene.

Sent from my SM-G960U using Tapatalk


They actually do. I remember my pocket 6K used to be good before I updated. Suddenly it looks bad.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 10:24 pm

Again, define appalling. Too high contrast, saturation weird, way too low or high exposure, what?

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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostSun May 15, 2022 10:34 pm

[quote="rNeil H"]Again, define appalling. Too high contrast, saturation weird, way too low or high exposure, what?

Sent from my SM-G960U using Tapatalk[/quote]

Overly saturated with harsh changes in the colours.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostMon May 16, 2022 12:48 am

It sounds like you're using the incorrect transforms. Either transform first to 709 in the Raw tab or a node in Fusion. This result is from using G4 to Video (Ursa) in the raw tab and the Delta Keyer with zero adjustments, just a random sample of the screen. It could definitely use some tuning but I'm not seeing any of what you're describing in this image.

Good Luck

P.S. The dude may as well be a soccer ball, the screen is lit better and there's twice the resolution for the key because of the composition. It wouldn't be reasonable to compare these shots with the same camera.

Key.jpg
Key.jpg (905.97 KiB) Viewed 2271 times
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostMon May 16, 2022 8:47 am

[quote="Howard Roll"]It sounds like you're using the incorrect transforms. Either transform first to 709 in the Raw tab or a node in Fusion. This result is from using G4 to Video (Ursa) in the raw tab and the Delta Keyer with zero adjustments, just a random sample of the screen. It could definitely use some tuning but I'm not seeing any of what you're describing in this image.

Good Luck

P.S. The dude may as well be a soccer ball, the screen is lit better and there's twice the resolution for the key because of the composition. It wouldn't be reasonable to compare these shots with the same camera.

[attachment=0]Key.jpg[/attachment][/quote]


That's where I am screwing up, could you send a print screen of the nodes?
I did convert in the Raw Tab.
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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostMon May 16, 2022 6:45 pm

[quote="Howard Roll"]It sounds like you're using the incorrect transforms. Either transform first to 709 in the Raw tab or a node in Fusion. This result is from using G4 to Video (Ursa) in the raw tab and the Delta Keyer with zero adjustments, just a random sample of the screen. It could definitely use some tuning but I'm not seeing any of what you're describing in this image.

Good Luck

P.S. The dude may as well be a soccer ball, the screen is lit better and there's twice the resolution for the key because of the composition. It wouldn't be reasonable to compare these shots with the same camera.

[attachment=0]Key.jpg[/attachment][/quote]
Hey man, Thank you. I didn't convert to R709 before. I used to go to blackmagic video and grade from there. Not Use R709 as colour space.
I didn't need to do it back with the canon so I never thought of doing it with BM.
I think this fixes my nightmare of issues.

I have also reseted the cameras and the LUT are working as they where before. Not sure what happened there.

Thank you to everyone for putting up with me and helping me out.
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Howard Roll

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Re: Green Screen Filming with a Pocket 6K or an Ursa Pro G2?

PostTue May 17, 2022 6:54 am

Glad you got it sorted. Another thing to look at is the exposure. The P6K was exposed at 1250 but the subject was so overexposed that I brought it back 2 stops just to get something normal looking. If the shot was exposed for 400 Native it would have more dynamic range and less noise. As evidenced in this situation, dropping the exposure prior to pulling the key yielded cleaner results as well.

Good Luck

MH.jpg
MH.jpg (573.89 KiB) Viewed 1987 times

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