Saturday, September 6, 2014

PE: Preroll and Postroll Options Interpreted

INTRODUCTION

The Preroll and Postroll options can be found in Premiere Elements*
  • Edit Menu/Preferences/General - Preroll and Postroll
  • Titler/Roll and Crawl Options - Preroll and Postroll
  • Capture Window'Device Control - Preroll Only
ISSUE

Setting these options in any one of the above areas does not appear to change the settings in the other two. What are these options supposed to do and how to get them to do it?

SOLUTION

Edit Menu/Preferences/General
Preroll and Postroll

Involvement: Video Track Playback and Preview Windows Trimming

The Preroll and Postroll settings in preferences each has unit in seconds, and each has its own 2 seconds default and a 60 seconds limit.

Video Track Playback Level

No matter what these settings are, just pressing the computer keyboard space bar in the Edit workspace starts at the beginning of the Timeline Video Track and ends at the end of the last item on the Timeline Video Track. So where are these "pre and post Timeline video spaces" defined by the Preroll and Postroll settings in preferences?

If Ctrl+Alt is held down and then the computer keyboard space bar is pressed, the Timeline Indicator will be commanded to the start of the Timeline Video Track 00;00;00;00, then move left to right and go beyond the end of the Timeline Video Track content by the amount of time = Postroll duration set in preferences. This is true if the Timeline Video Track content starts at the beginning of the Timeline Video Track or  starts at any distance from the start of the Timeline Video Track. Never is there any evidence of the Preroll setting.

Preview Windows Trimming

If a video is trimmed in its Preview Window, no matter what the preferences Preroll and Postroll settings are, just pressing the computer keyboard space bar starts the Preview Windows playback at wherever the Timeline Indicator is positioned there and ends at the last frame of the video being previewed, not a at a distance from the end of the trim as defined by a Postroll setting.

However, if Ctrl+Alt is held down and then the computer keyboard space bar is pressed,
  • the Timeline Indicator will be commanded to a point on the Preview Windows Timeline at a distance from the beginning of the trim as defined by the Preroll setting.
  • and end at a distance from the end of the trim as defined by the Postroll setting
This suggests that the Preroll and Postroll settings in preferences are targeted at Preview Window Timeline quicker assess to the In and Out points of the trim for re-evaluation of those points rather rather being targeted at involvement with Preroll and Postroll Ads for video as might be implied by the definition of these options often seen online.

Titler/Roll and Crawl Options
Preroll and Postroll

Involvement: Titler, Roll and Crawl Titles


Preroll and Postroll options are available for Roll and Crawl titles in the opened Titler as alternatives for the Start Off Screen and End Off Screen options respectively in the Roll/Crawl Options dialog*. These Preroll and Postroll options each
  • use frame as the unit of time, not second
  • appear to have a default 0 frames and have a 5000 frames limit
Preroll is disabled when Start Off Screen is selected; Postroll is disabled when End Off Screen is selected. And, conversely, Start Off Screen is disabled if Preroll is selected; End Off Screen is disabled if Postroll is selected.

If Text Menu/New Text/Default Roll is selected, followed by Text Menu/'Roll/Crawl Options", the default Roll/Crawl Options dialog presents as shown in Figure 1.

Figure 1. Default Roll's Roll/Crawl Options Dialog


If Text Menu/New Text/Default Crawl is selected, followed by Text Menu/Roll/Crawl Options, the default Roll/Crawl Options dialog presents as shown in Figure 2.


Figure 2. Default Crawl's Roll/Crawl Options Dialog.

But, what happens after the Preroll and Postroll are set instead of Start Off Screen and End Off Screen? A few of the scenarios might be for a 5 second title

Preroll set at 30 frames
Start Off Screen disabled
Postroll set a 0 frames
End Off Screen enabled
The beginning of the Title stays on screen at the start position for 30 frames (1 second in a 30 frames per second system) and then rolls or crawls off screen

Postroll set at 30 frames
End Off Screen disabled
Preroll disabled
Start Off Screen enabled
The Title starts off screen, moves on screen to display the title text, stops at the Title's last text entry without moving off screen and maintains that view until the end of the playback of the Title file. The duration between the stop and the end of the Title file is determined by the Postroll setting.

Example 1
5 second rolling title clip
Postroll set at 100 frames (3.30 seconds in a 30 frames per second set up)
End Off Screen disabled
Preroll disabled
Start Off Screen enabled

Figure 3. Example 1. Titler Roll/Crawl Options Postroll Setting = 100 Frames.

 Example2
5 second rolling title clip
Postroll set at 50 frames (1.67 seconds in a 30 frames per second set up)
End Off Screen disabled
Preroll disabled
Start Off Screen enabled

Figure 4. Example 2. Titler Roll/Crawl Options  Postroll Setting = 50 Frames.

Edit Menu/Preferences/Device Control
Preroll Only

Involvement: DV HDV Capture Firewire

A Preroll option can be found under Edit Menu/Preferences/Device Control** relating to DV HDV Capture. Adobe writes
          Preroll
Specifies the number of seconds you want Adobe Premiere Elements to roll the tape before the specified start time so that the device can attain a constant speed. The tape plays for the specified amount of time before recording begins.
This Preroll option has unit in seconds, has default of 2 seconds, and has a 60 seconds limit.


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*Features were verified on Premiere Elements 12 on Windows 7 Professional SP1 64 bit and
appear to be the same for Premiere Elements 4 through 12 Windows.
**Device Control can also be accessed from the Capture Window (in Premiere Elements 12/12.1, see Add Media/DV Camcorder or HDV Camcorder).