Panasonic AG-DVX100

With the release of this new camera by Panasonic, there seems to be a lot of confusion surrounding the two different 24p modes that the camera is capable of shooting.

To use Panasonic terms, there is 24p and Advanced. For the sake of this document, I will use the terms:

" Standard": Traditional pulldown with the 2:3:2:3 cadence (F5 setting on camera)
" Advanced": New pulldown with the 2:3:3:2 cadence (F6 setting on camera)

The confusion seems to stem from the fact that in order to go back to film, the user must use the "advanced" pulldown mode. This is not true. Using "standard" or "advanced" is a decision based on the editing application used for the post production. If the application used is capable of creating 24-frame progressive from the NTSC signal, then either type of pulldown can be output to film.

The reason for the advanced pulldown mode of the camera (F6 setting) is to allow native DV editing applications the ability to easily create 24p from the NTSC signal. This is because of the amount of time it takes to convert the fields of the "C" frame (see diagram) to create a new progressive frame. The "C" frame within a "standard" pulldown cadence is comprised of 2 fields but from two different frames - starting with field 2 and then field 1. In order to make a progressive frame from this type of pulldown requires that the field order be flopped and then a progressive frame created. Another issue with doing this over FireWire and native DV is the decompression that is needed in order create this type of frame.

The chart shows the two types of pulldown from a 24 frame capture. The middle row are the original 4 frames representing 1/6th of a second (the pattern repeats itself 6 times every second). The top row is a "standard" pulldown cadence and the fields that are captured are represented with green arrows. The bottom row is the "Advanced" pulldown cadence.

Current hardware capture cards working from a NTSC signal, and have the ability to inverse telecine in real time expect to see the standard pulldown cadence. These cards/systems include Avid, AJA Kona, etc. With the release of Avid Xpress Pro v.5.1, the standard, or NORMAL pulldown can also be removed upon capture directly over FireWire.

The "advanced" cadence allows a native DV over FireWire to just "drop" the "C" frame in order to recreate the original 24p capture. There are applications that can post-process the captured DV media and create the 24 progressive frames (DVFilm).

Most NLE's today can capure ADVANCED pulldown over FireWire and remove the "C" frame leaving only the orignal 23.976 progressive frames. Only Avid allows for NORMAL pulldown to be removed during capture over FireWire. Most NLE's will also allow output back over FireWire as NORMAL or ADVANCED to NTSC. Apple FCP 4.5 and Avid Xpress Pro 5.0 and later allow this feature.

Something to be considered is whether the footage will be edited at native 24p. If not, and the footage is going to be integrated into existing 30i footage, or if there will be a mix of film and 24p DV, then you will want to shoot with the "standard" pulldown to keep a consistent look to the motion.

The use of "advanced" pulldown almost dictates the use of a inverse telecine or frame removal because the cadence is a bit easier for the eye to detect since the two long frames (3 fields) are in sequential order creating more of a bump to the motion than with "standard" pulldown where the long frames are spread out between the short frames.

When outputting to NTSC for broadcast or MPEG2 encoding from an NTSC output, you will want to make sure the render or the playback is done with "standard" pulldown. The only time you would output with "advanced" pulldown is if you are archiving the edited material and want to recapture on another native DV editing system.

Basic Rules of thumb

Shoot NORMAL Pulldown

1. Will be mixing with 30i or other film originated footage
2. Will be capturing as 1:1 NTSC (24p) for final color correction etc. (Avid or other SDI based capture boards, etc.)

Shoot ADVANCED Pulldown

1. When using native DV editing application with capture over Firewire (capture may need to be processed depending on the editing application being used).

Regardless of which pulldown was used for capture, as long as the editing application can recreate the original 24 progressive frames, the output can easily go to film, NTSC and PAL.

updated 11/26/05