Bluescreen + HVX = damn beautiful

M

microbob

Active member
I needed to shoot a news monologue (Keith Oberman style) that played on a TV in the background of one of my scenes. It needed to deliver a very specific message, so I shot it on blue screen and built my own news looking environment.

I didn't quite go all "CNN" or "FOX" with crawls all over the place, but I think it came out looking pretty good given the fact that I only spent one evening editing it together.

My poor actor had a 102 fever and was sweating like a man on death row, but he still did a great job

- I used a vector scope to dial in a perfect blue channel. I think we shot at around 75IRE. You have to put the HVX in SD mode in order to get this out the FireWire to the PC where I used DV Rack's scope. Then I used the chroma shift in the HVX to slide just a bit for perfect alignment with the blue channel.

- All the keying was done in FCP and was easier than I expected.

- The HVX was setup using the "less noisy" settings that Barry Green recommends in his HVX book.

- I shot in 720p. I also uprezzed the Digital Juice footage to 960x720 which is used as the background.

- The lighting wasn't perfect, but we only had 20 minutes setup time and then we had to start shooting. There are a few small shadows around his hair on the right side of his head.

- The final result: - http://rm-fr.com/thewarinside/monolog_853x480_h264.mov

setup_one.jpg


setup_two.jpg


monolog_blue.jpg
 
microbob said:
- I used a vector scope to dial in a perfect blue channel. I think we shot at around 75IRE. You have to put the HVX in SD mode in order to get this out the FireWire to the PC where I used DV Rack's scope. Then I used the chroma shift in the HVX to slide just a bit for perfect alignment with the blue channel.
Click to expand...
If you have DV Rack HD, then you can do this in DVCPro50 and DVCProHD as well, provided you aren't using a native (PN) recording mode.

You could even do the calibration in P mode, and then switch to PN for your recording, or leave it in P and record to DV Rack.
 
THoff said:
If you have DV Rack HD, then you can do this in DVCPro50 and DVCProHD as well, provided you aren't using a native (PN) recording mode.

You could even do the calibration in P mode, and then switch to PN for your recording, or leave it in P and record to DV Rack.
Click to expand...

Didn't have the HD version, but good to know it can "see" the HD output from the firewire and I wouldn't have to switch over to SD mode to do the setup. At one point I forgot to save the settings in a scene file, swiched over to HD and scratched my head trying to figure out why the blue screen suddenly looked purple.

This was my first try at doing this and was surprised at how well it worked out. I still could soften the edges to remove the slight green hue around his jacket and maybe do some work to reduce the shine on his face.

I was told the keying is much (much!) easier because the DVCProHD contains twice as much color information as HDV.
 
Jim Arthurs said:
Good job! If you check on your scopes in FCP, I think you'll find that the screen IRE is between 30 and 40 IRE...
Click to expand...

Wow, you are absolutely correct. I just checked and they range between 30 and 40...I must have spaced out while on set and no telling what I was looking at.

Thanks for pointing this out...I don't want to go leaving bogus information on the forum.

fcp_scope.jpg
 
Dude needs a sweat rag.

Looks nice though, except for the bizarre way that he's looking off to the side. Seems like a controlled interview rather than a newscast.
 
BrandonC said:
Dude needs a sweat rag.

Looks nice though, except for the bizarre way that he's looking off to the side. Seems like a controlled interview rather than a newscast.
Click to expand...

Yah, dude had like a 102 degree fever and got myself and my producer sick 3 days before our shoot. We almost died that weekend (just kidding, but not really). We toweled him off and powered him up, but it just didn't help.

My fault on him looking off to the side. Fortunately we filmed this playing on an actual TV while doing a slow dolly in over my actor's shoulder as he sat on the couch. It is far off enough that none of the major flaws show up and because of the angle of the dolly, it *almost* feels as if the guy is looking right at my actor. Still though, he really needed to be looking closer to the camera lens.

We also shot a woman that day on the blue screen but she had BLUE eyes! We switched to a green screen for her shots, but I never could get the good key on green as I did with blue. I only had a small window of time to get this shot, spiffied up to look like a news program, burn it to DVD, and get it to the set to play in the scenes.

It was a heck of a learning experience for me having never done any type of blue/green screen before. I was really worried because our access to the studio that had the blue/green screen was just days before our shoot.

Fortunately, there are a few good tutorials, plus info in this site, that helped me *tremendously*:

- http://www.kenstone.net/fcp_homepage/chroma_key_fcp_hd_monahan.html
- http://www.imageshoppe.com/HVX_bluescreen2.html

Some shots of her against both the blue and green screen:

k_green.jpg


k_blue.jpg
 
i love the blind deaf and dumb bit. if this is just going to be in the background of another scene, are you hoping it will have a subliminal effect? :)
 
jenningsp said:
i love the blind deaf and dumb bit. if this is just going to be in the background of another scene, are you hoping it will have a subliminal effect? :)
Click to expand...

The way the scene is constructed, my actor (a US Marine just back from his 2nd tour in Iraq) and is sitting on the couch just after having a telephone conversation. He clicks on the news and this monologue is running. We slow dolly into him over the top of the TV mixed with cuts of a slow dolly over his shoulder towards the TV. We end up with a somewhat of a MCU on the TV and CU on the actor. Then the phone rings again.

I threw this clip together JUST NOW, so it has NO color correction, NO audio fixes, or NO match actions cuts. It is just a BASIC IDEA of how the news/monologue was used in the film:

- http://rm-fr.com/thewarinside/act-ii-scene-iii_demo_no_cc.mov
 
Microbob,

Your greens and blues appear to be a stop or two hotter than your talent. A rule of thumb with lighting a keyed background is to keep your blue/green a stop below the talent's light.
 
Mr. Blonde is that for film or video? Looks like to me that both Jim Arthurs and Microbob are having great success keying with the HVX while having such bright backgrounds.
 
Pretty good effort for a first attempt. The key came out well. The kicker on him seems a little off, just an opinion.
 
Mr. Blonde said:
Microbob,

Your greens and blues appear to be a stop or two hotter than your talent. A rule of thumb with lighting a keyed background is to keep your blue/green a stop below the talent's light.
Click to expand...

Ahhh, good to know. When I shot the green screen it was way blown out with zebras all over the place at 80%.

I had access to this stuido for 4 hours and it was my first attempt, so I was flying by the seat of my pants. Next time I do this, I'll nail it 100%.

Woot!

-mb
 
Mr. Blonde said:
Microbob,

Your greens and blues appear to be a stop or two hotter than your talent. A rule of thumb with lighting a keyed background is to keep your blue/green a stop below the talent's light.
Click to expand...

I'm finding with the HVX that the best screen level to keep noise as low as possible in those transitional areas between screen and talent is 60 to 65 IRE for green, and 30 to 40 IRE for blue. The green screen example of Microbob's is about 80 IRE... Still, I'd wager just looking at the still that it will still key nicely in AE with Keylight.

Personally, 80 IRE is too hot, but if the screen is even and nothing is any hotter than that... maybe not for the HVX. The problem is, at those levels, the green channel starts clipping to pure white, while the other two channels keep rising to meet it... this can produce odd fringing colors that can never be surpressed with standard tools.

In addition, you have to pound more and more white light to counter-act the spill when working at those levels...

Incidentally, the higher quality paints are designed to be a the "proper" luma with the proper amount of chroma purity when lit to the same level as the talent's key...
 
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