Jump to content


Photo

Shooting a TV screen.


  • Please log in to reply
4 replies to this topic

#1 Nathan D. Lee

Nathan D. Lee
  • Basic Members
  • PipPip
  • 69 posts
  • 2nd Assistant Camera
  • Salt Lake City

Posted 10 February 2007 - 05:47 PM

Come Monday I will be shooting a scene for a fake documentary on 16mm with a fixed 180 degree shutter.

The scene requires us to see a TV screen. We are looking for the same kind of crappy TV look as the "Rex Kwon Do" commercial in Napoleon Dynamite.

I consulted the ASC manual and it offered some solutions that are not viable for us, but said nothing of what the results would be if I simply shot the TV at 24fps. I am guessing thats what Napoleon did because of the low flicker (which I like) but am worried that the flicker will be extreme.

I know the color temp issues, so I simply need to know if the frame rates will work close enough or if I should try a composite later (which I don't want to do because it is wrong for the feel of this).

Let me know if yo have some tips or answers.

Nathan
  • 0

#2 Mark Wilson

Mark Wilson
  • Basic Members
  • PipPip
  • 28 posts
  • Other

Posted 10 February 2007 - 07:12 PM

Come Monday I will be shooting a scene for a fake documentary on 16mm with a fixed 180 degree shutter.

Let me know if yo have some tips or answers.

Nathan


Basically, if you shoot NTSC video at 24fps you will get one or two thin, slightly flickery horizontal lines slowly creeping down the screen. It's not terribly noticeable, and lots of movies and TV shows have been released with images like that, and nobody seems to notice.

However if you want perfect results you need to have the camera running at the same frame rate as the video. One cheap workaround is to have the video transferred to 25 fps PAL and run the camera at crystal 25fps if this is available . Note: You still have to move the framing bar off the viewfinder screen before the action starts.

The main problem with this technique is that you can't do sync-sound since the 4% pitch change will be very noticeable when you slow the film (and sync tape) back to 24 fps.

The usual workaround for that was to always have the actor's back to the camera when he/she is supposed to be speaking with the TV in shot, and then dub their dialogue in later. That avoids the need for lip-syncing.


In the past this still tended to a fairly pricey undertaking if you didn't live in a PAL country, but nowadays this can be done economically by making an NTSC recording on DVD and playing it back with a "international" model DVD player (ie the ones you buy in department stores for $29.95), with the output set to PAL.

Most of these are designed to work anywhere in the world and the signal output can usually be set to either PAL or NTSC, (but check this) with very little difference in the image quality.
  • 0

#3 David Mullen ASC

David Mullen ASC
  • Sustaining Members
  • 19759 posts
  • Cinematographer
  • Los Angeles

Posted 10 February 2007 - 08:45 PM

Basically, if you shoot NTSC video at 24fps you will get one or two thin, slightly flickery horizontal lines slowly creeping down the screen. It's not terribly noticeable, and lots of movies and TV shows have been released with images like that, and nobody seems to notice.


Only if he could shoot with a 144 degree shutter -- with a fixed 180 degree shutter, he'd get big roll bars, not thin lines.

A 144 degree shutter reduces the bars to thin lines. Shooting at 23.976 fps stops them from moving. Using a phase control box allows you to place them on the screen where you want them (usually either two lines, one at the top third and one at the bottom third of the screen -- or one line, but in the middle.)

Either he needs to shoot at 29.97 fps, or use an LCD screen built into the CRT monitor housing as a prop TV.
  • 0

#4 Nathan D. Lee

Nathan D. Lee
  • Basic Members
  • PipPip
  • 69 posts
  • 2nd Assistant Camera
  • Salt Lake City

Posted 10 February 2007 - 09:03 PM

Well I just found out we will be using an Eclair NPR as opposed to an ACL. The NPR has a variable shutter in five degree increments.
It is adjustable in 5 degrees from 5 to 180. So should I try for 145?
Thanks!

Nathan
  • 0

#5 David Mullen ASC

David Mullen ASC
  • Sustaining Members
  • 19759 posts
  • Cinematographer
  • Los Angeles

Posted 10 February 2007 - 09:54 PM

I did this in film school with Eclair NPR's and it worked pretty well -- you just get this thin rolling line with a 144-ish shutter speed.
  • 0


CineTape

Visual Products

Glidecam

Ritter Battery

Willys Widgets

Wooden Camera

Paralinx LLC

Media Blackout - Custom Cables and AKS

Rig Wheels Passport

Aerial Filmworks

Abel Cine

Gamma Ray Digital Inc

Technodolly

CineLab

The Slider

Broadcast Solutions Inc

Metropolis Post

rebotnix Technologies

FJS International, LLC

Opal

Tai Audio

The Slider

Technodolly

Media Blackout - Custom Cables and AKS

Tai Audio

Aerial Filmworks

FJS International, LLC

Metropolis Post

Opal

Gamma Ray Digital Inc

Abel Cine

Wooden Camera

Willys Widgets

CineTape

Broadcast Solutions Inc

rebotnix Technologies

Paralinx LLC

Visual Products

Ritter Battery

Glidecam

CineLab

Rig Wheels Passport