Jump to content


hd images too dark


  • Please log in to reply
3 replies to this topic

#1 kingkeyan

kingkeyan
  • Guests

Posted 07 June 2005 - 01:28 PM

I shot some scenes with the sony cinealta f900 and after it was downconverted the director called me and told me the images were too dark, is it a downconversion issue because they put an hd image on vcr? or is the monitor he is watching too dark?

my exposure was correct going into camera and everything on the monitor looked fine as well

any ideas?
  • 0

#2 David Mullen ASC

David Mullen ASC
  • Sustaining Members
  • 20074 posts
  • Cinematographer
  • Los Angeles

Posted 07 June 2005 - 03:33 PM

I shot some scenes with the sony cinealta f900 and after it was downconverted the director called me and told me the images were too dark, is it a downconversion issue because they put an hd image on vcr? or is the monitor he is watching too dark?

my exposure was correct going into camera and everything on the monitor looked fine as well

any ideas?

<{POST_SNAPBACK}>


Either your monitor or his monitor is probably incorrect. Downconversions generally don't change brightness, although someone could have monkeyed with the pedestal or something.

Sometimes you run into digital downconversions setting black at "0" (as it is in HD) without the 7.5 IRE set-up for NTSC, so sometimes a copy on DVD may look like the blacks are crushed and shadow detail is lost. I've seen a LOT of variations in black levels these days and I'm sure some of it is the whole 7.5 IRE set-up for NTSC issue and whether it is missing or not. I'm not an expert in this area, but I believe that one approach is to work with video black at "0" throughout digital post and then only add the 7.5 IRE set-up at the end of post, which is why it can be missing in dailies on DVD. Just a theory.
  • 0

#3 kingkeyan

kingkeyan
  • Guests

Posted 07 June 2005 - 06:24 PM

thanks for the reply, ill ask the company that did the downconverts and ask them what the deal is, and ill let the director know about the 7.5 IRE setup issue, seems very odd, i was opened up all the way and the monitor image looked great, either way i think the brightness can be pumped up in post if im not mistaken
  • 0

#4 Mike Brennan

Mike Brennan
  • Basic Members
  • PipPipPipPip
  • 581 posts
  • Cinematographer
  • London

Posted 09 June 2005 - 07:37 PM

thanks for the reply, ill ask the company that did the downconverts and ask them what the deal is, and ill let the director know about the 7.5 IRE setup issue, seems very odd, i was opened up all the way and the monitor image looked great, either way i think the brightness can be pumped up in post if im not mistaken

<{POST_SNAPBACK}>


It is possible to screw up the image on the Sony 24inch monitor by not terminating the YpPbPr outputs.
Yes they are not self terminating.
It is also possible to get a bright looking picture by winding the contrast control up.
Finally all HDCAM decks have a complete set of adjustable video controls, like gamma detail ect, for each output.




Mike Brennan.
  • 0


Paralinx LLC

rebotnix Technologies

New Pro Video - New and Used Equipment

FJS International, LLC

Ritter Battery

Broadcast Solutions Inc

Visual Products

CineTape

The Slider

Abel Cine

Gamma Ray Digital Inc

Aerial Filmworks

Rig Wheels Passport

Technodolly

Metropolis Post

Wooden Camera

Tai Audio

Media Blackout - Custom Cables and AKS

Glidecam

CineLab

Willys Widgets

Willys Widgets

rebotnix Technologies

Metropolis Post

FJS International, LLC

The Slider

Ritter Battery

CineLab

Media Blackout - Custom Cables and AKS

Rig Wheels Passport

Gamma Ray Digital Inc

CineTape

Glidecam

Technodolly

New Pro Video - New and Used Equipment

Aerial Filmworks

Paralinx LLC

Visual Products

Wooden Camera

Broadcast Solutions Inc

Abel Cine

Tai Audio