PE: About Disabling Sound For Whole Audio Track

INTRODUCTION

Recently, in an Adobe Premiere Elements Forum thread, a Premiere Elements 13 question asked "How to disable the sound for a whole audio track in contrast to adjusting individually the volume for any audio clip placed in that track?" The originator of the thread claimed that whole audio track muting could be done in other versions of Premiere Elements or in Premiere Pro, but not Premiere Elements 13 (current version).

In Premiere Pro 2.0 (only pro version available to us), it was found that each of the numbered audio tracks has a Toggle Track Output icon that a user can use to mute the sound for a whole audio track. See Figure 1.

Figure 1. Premiere Pro 2.0 And Its Toggle Track Output Icon To Mute The Sound From A Whole Audio Track.

The more recent situation for Toggle Track Output in Premiere CC can be found in the book excerpt titled "Working with the Timeline in Adobe Premiere Pro CC" (Jan Ozer, Peachpit Press). It would appear that muting whole audio track sound is still possible in this later version also.

In reviewing the Premiere Elements side of things for this question, Premiere Pro's Toggle Track Output function is found in Premiere Elements 10 and earlier in their Sceneline workspace ONLY. It can been found there in the form of a Change Track Volume icon which exists to the left of the Soundtrack, Narration Track, or Video. The Change Track Volume icon is represented by a Speaker for Soundtrack, a Microphone for Narration, and a Filmstrip for Video (Audio Track 1).

See Figure 2.

Figure 2. Premiere Elements 10/Quick Workspace And Its Change Track Volume Icon To Mute The Sound From A Whole Audio Track.

Moving the volume slider to the bottom of the vertical bar mutes the sound from its associated whole  audio track in the Timeline workspace as well as in the Sceneline workspace. And, the sound remains muted in Timeline and Sceneline workspaces until the user resets the volume slider in the Sceneline workspace. This can create a problem for the user who mutes the sound in the Sceneline workspace, moves to the Timeline workspace, does not remember muting the audio track(s) in the Sceneline workspace, has no audio in Timeline workspace, and begins a major troubleshooting scheme to try to find out why no audio in Timeline workspace.

There is no Change Track Volume icon with associated volume slider in Premiere Elements 11, 12/12.1, and 13/13.1. However version 11, 12/12.1, 13/13.1 Quick workspace (a Sceneline workspace counterpart) does have the Filmstrip icon, Microphone icon, and Speaker icon for its audio tracks. But the icons here refer to adding audio clips to audio tracks and not shutting down whole audio tracks.

• Speaker icon pop up description is Add audio sound clips to this track

• Microphone icon pop up description is Add narration to this track

• Filmstrip icon pop up description is Add video clips/photos to this track.

See Figure 3.

Figure 3. Premiere Elements 13/13.1 Quick Workspace Speaker, Microphone, And Filmstrip Icons Without Change Track Volume Function.

ISSUE

If Premiere Elements 11, 12/12.1, and 13/13.1 no longer have the Change Track Volume icon to mute the sound for a whole audio track in its workspaces, how can the whole audio track sound be muted in these later versions? Can the Audio Mixer (Expert workspace tool only) be used for this purpose?

SOLUTION

No way has been found to shut off the sound to a whole audio track in the Expert or Quick workspaces of Premiere Elements 11, 12/12.1, and 13/13.1. And, the Audio Mixer "Mute" button in these versions is not a replacement function for Premiere Pro Toggle Track Output or Premiere Elements 10 and earlier Change Track Volume.

 See DISCUSSION for more comments on Audio Mixer and its Mute Button.


 DISCUSSION

The Audio Mixer "Mute" button in the opened Audio Mixer is for Audio Mixer internal use only, muting the sound of one or more audio tracks when trying to adjust the volume settings of other audio tracks. According to Adobe document "Adobe Premiere Elements Help/Mixing and Adjusting Volume"

To mute a track while mixing, click Mute. This option does not mute the track permanently—only while mixing.

The Audio Mixer shines when it is automatically keyframing the volume of audio clips on the project's numbered audio tracks, Narration Track, and Soundtrack as the Timeline plays back and the user adjusts the volume slider in each of the project's audio tracks represented in the opened Audio Mixer.

This blog exploration was triggered by what appeared in a recent Adobe Premiere Elements thread "Re: Premiere Elements 13 mute track" in which a replier wrote

If you set the slider (say, all the down to zero) for a track when your video is not playing, the level of the track will be set overall.

That was not found to be true, and our results in evaluating this statement were very interesting. Some examples

SETUP 1
If 3 music clips were side by side in the Soundtrack, the Timeline Indicator positioned on music clip 2, Timeline Soundtrack not playing, Audio Mixer opened, Audio mixer Soundtrack Volume slider set at infinity (no sound), and Timeline Soundtrack not playing,

RESULT       
It was only the volume of music clip 2 that was muted - not also music clip 1, music clip 3 or the whole Soundtrack in the Audio Mixer. When the Audio Mixer was closed, music clips 1 and 3 had sound in the Expert workspace Timeline Soundtrack, and music clip 2 was muted. And, any subsequent additions to this Timeline Soundtrack in the Expert workspace presented with sound. It did not matter whether or not the clips were selected at the onset. The clip muted appeared to depend on which of the clips the Timeline Indicator was placed.

SETUP 2

If 3 music clips were side by side in the Soundtrack, the Timeline Indicator placed at the beginning of the Timeline, Timeline Soundtrack not playing, Audio Mixer opened, the Audio mixer Soundtrack Volume slider set at infinity (no sound), and the Timeline Soundtrack playback started

RESULT        
      
When the playback stopped and the Audio Mixer was closed, Expert workspace Timeline Soundtrack  music clip 1 had no sound, music clips 2 and 3 had sound, and all subsequent music files added to the Timeline Soundtrack had sound.

Our suggested workaround for getting all 3 Soundtrack music clips muted in the same Audio Mixer session was

• Open Audio Mixer and drag Soundtrack Volume slider to no sound

• With the mouse cursor, hold down the volume slider at no sound throughout the whole Soundtrack playback

• When the Soundtrack playback is stopped and the Audio Mixer is closed, all 3 Soundtrack clips will be muted in the workspace. But any subsequent additions to the Soundtrack will present with sound.

COMMENTARY

The DISCUSSION details are presented not to demonstrate what the Audio Mixer can do (that for another time), but rather to point out what it cannot do with respect to "mute" of a whole audio track in the Expert and Quick workspaces of Premiere Elements 11, 12/12.1, and 13/13.1.

This work was done of Windows 7 Professional SP1 64 bit computer and confirmed on Windows 8.1 64 bit computer.


Work in Progress

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PE 11, 12, 13: More About Project Presets

INTRODUCTION

When Premiere Elements 11, 12, or 13 is opened to a new project, the default project preset is for 1080i*, either 1080i25 (if PAL setup) or 1080i30 (if NTSC setup).

If the program is installed with a PAL TV Format, then the project's default project preset is
PAL
AVCHD
Full 1080i25
If the program is installed with a NTSC TV Format, then the project's default project preset is
NTSC
AVCHD
Full 1080i30
The above default project preset is overwritten for a new project
a. automatically based on the properties of the first video dragged to the Timeline as the first file.
or
b. the user manually setting the project preset using File Menu/New/Project before the source media are imported into the project

Premiere Elements 11, 12/12.1, and 13/13.1 were designed so that the project sets the project preset (project settings) automatically based on the properties of the first file dragged to the Timeline. This automatic setting of the project preset depends on the program analyzing correctly the file properties (properties such as clip dimensions, frames per second, pixel aspect ratio, field order) and overwriting its default 1080i project setting with one of the project's project presets that matches the properties of the source file.

As an example, if the source is 1920 x 1080p30 video and Premiere Elements analyzes it correctly when it is the first video dragged to the Timeline as the first file, then the default project preset (1080i30) is overwritten with
NTSC
DSLR
1080p
DSLR 1080p30 or 1080p30@29.97.

But, if it cannot find the match for project preset and properties of the source file, then it uses its default 1080i project preset

NTSC

AVCHD

Full HD1080i30

There is no guarantee that a project will do the automatic set properly for every source video format. So, the first time a video from a different source is used, best to check Edit Menu/Project Settings/General to see what the project has set for the project preset using Adobe's automatic way. If the setting is 1080i instead of what it should be, then manual setting of the project preset is indicated, File Menu/New/Project**.

An important note in all this.....it has been found that, if photos and videos are to be imported into a new project and photo is dragged into the Timeline as the first file to be dragged to the Timeline, then the project preset will always be and remain 1080i (the project's default) even if the next drag into that Timeline is 1080p video.

ISSUE

How can the default project preset that exists when the project opens be changed

• 1080i25 instead of 1080i30 or 1080i30 instead of 1080i25

• from 1080i25 or 1080i30 to something else

SOLUTION

Changing Default Project Preset That Exists When The Project Opens (Before Source Media Are Imported)

1080i25 Instead Of 1080i30 Or 1080i30 Instead Of 1080i25
and
From 1080i25 Or 1080i30 To Something Else

During product installation set
NTSC TV Format for NTSC 1080i30 default project preset
PAL TV Format for PAL 1080i25 default project preset

(The above is applicable to Premiere Elements 11 and 12/12.1, but not Premiere Elements 13/13.1 where the NTSC TV Format or PAL TV Format choice appears to have been removed from the installation process. At the present time, there was no solution found for the Premiere Elements 13/13.1 situation. See COMMENTARY section after SOLUTION section.)

Once the NTSC TV Format or PAL TV Format is established and the installation complete, the TV Format choice cannot be changed without doing a program uninstall/reinstall selecting the TV Format wanted.

The choices for default project preset when the project opens (before source media import) are either 1080i25 or 1080i30, and no user additions to those two choices were found possible.

Changing The Project Preset For The Project After The Source Media Have Been Imported And Editing The Timeline Content Is In Progress

Typically it is written that, if incorrect project settings are realized after the project is begun, the user has to start a new project to correct the situation. For Premiere Elements 11 and 12/12.1 we have found a way, in some cases, to change these project settings without having to start a new project. This is done by editing the Notepad document of the save project file (.prel).
http://atr935.blogspot.com/2013/05/pe11-changing-project-settings-without.html 
It was not found possible to apply this approach to Premiere Elements 13/13.1 project due to the coding that presented in the Notepad document of the saved Premiere Elements 13/13.1 project file. 

COMMENTARY

No where in Premiere Elements 13 installation, do we see the dialog which lets the user customize by selecting NTSC TV Format or PAL TV Format.

Instead, all that the user gets are places to set language and country which are presumed to set automatically the default project preset as well as the language in the program. But it is not working for default project preset. As an example, Premiere Elements 13 installation/language and country French and France got us the program in French but a NTSC default project preset instead of the expected PAL one.

We went back to Premiere Elements 11 installation and had no problem setting for English (North America) and PAL TV Format so that we arrived in the opened new project with a default project preset of PAL AVCHD Full HD1080i25. But the installation for 11 has the dialog for NTSC TV Format or PAL TV Format. We have gone back to 13 and tried the installation settings of English (North America) and selecting United Kingdom as the country. Still NTSC default project preset settings, not PAL.

At this point, our major questions are

• What happened to the NTSC TV Format and PAL TV Format dialog in 13 installation?

• Why is language and country in 13 installation not directing the program to the appropriate default project preset***?
  

The most current Adobe document that could be found on the topic of its Project Settings and Presets does not seem to offer answers to these questions. Please refer to
https://helpx.adobe.com/premiere-elements/using/project-settings-presets.html

Also see the April 29, 2013 blog post titled "PE 11: Accuracy of Automatic Project Preset (New Project Dialog) Setting
http://www.atr935.blogspot.com/2013/04/pe11-accuracy-of-automatic-project.html


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*1080i referred to in this blog is 1920 x 1080 @ either 25 or 29.97 interlaced frames per second with Field Order = Upper Field First. "Default Project Preset" represents the project settings when a new project is opened (and before source media is imported into the project).

**Manual setting of the project preset is done...

• Open the project to the Expert workspace, and go to File Menu/New Project and Change Settings.

• In Change Settings, set the project preset to match the properties of the source media. OK out of there.

• In the New Project dialog that opens, rename the project and make sure to have a check mark next to "Force Selected Project Setting on This Project". OK out of there.

• Back in the Expert workspace, import your source media using Add Media/ choice.

***Just a reminder concerning the distinction between "default project preset" and "project preset" being used in this blog post. "Default project preset" represents the project settings that exist when a new project is open, and the source media have not yet been imported. In contrast, "project preset" represents the projects settings established by the project (automatically) based on the properties of the first file drag to the Timeline or by the user manually setting the project preset (File Menu/New/Project) before the source media are imported. 





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PE: Non Red Key. What is it?

INTRODUCTION

Opportunities for green screen keying are fewer in Premiere Elements* Mac than Premiere Elements* Windows. The keying effects of Blue Screen Key, Green Screen Key, Chroma Key, and RGB Difference Key are Windows Only. Many suggest Videomerge effect as the green screening tool for the Premiere Elements Mac user, while Difference Matte Key seems to be the better choice. Recently the Alpha Adjust which which is accessed in the Premiere Elements Mac and Windows keying effects was explored for green screening and found not to be applicable to the task. There are lots of keying effects to study and learn how they are used to convert color or brightness in an image to transparency.

 ISSUE

Are there any more choices for green screening tool(s) for the Premiere Elements Mac user other than
Videomerge and Difference Matte Key? Apparently there is at least one more, Non Red Key which is available to Premiere Elements Mac as well as Windows users. Non Red Key has been around since the days of Premiere Elements 4. So, time to recognize it and see what it can do.

SOLUTION

It was found that Non Red Key should be usable as alternative for Videomerge and Difference Matte for the Premiere Elements Mac user with green screen projects 

The Adobe document "Adobe Premiere Elements help / Superimposing and transparency" lists the "Color-based keying effect"
Videomerge
Blue Screen Key
Green Screen Key
Non Red Key

Non Red Key is available in both Premiere Elements Mac and Windows. And, Adobe describes it as an good alternative for Green Screen Key or Blue Screen Key and states

Use the Non Red Key to key out green screens when you need to control blending, or when the Blue Screen or Green Screen Keys don’t produce satisfactory results.

Non Red Key was looked at as a green screen tool using Premiere Elements 13/13.1 on Windows 7 Professional SP1 64 bit and video samples (AVCHD.mp4 1920 x 1080p30). And, the results were compared to those from use of Green Screen Key or Blue Screen Key.

RESULTS 

Non Red Key

Green to Transparency

Before Image

Green Background Color = OCF137

After Image**

Threshold - 48%; Cutoff = 12.8%; Defringing = None; Smoothing = None; No Check Mark Next To "Mask Only"

After Image As Video With Baseball Field Background Viewed In Transparent Area

Blue to Transparency

Before Image

Blue Background Color = 3AAFE6

After Image**

Threshold = 12.2%; Cutoff = 9.5%; Defringing = None; Smoothing = None; No Check Mark Next To "Mask Only"

Yellow to Transparency

Before Image

Yellow Background Color = EEF10A

After Image**

                              Did not work. This did work with Chroma Key.

Green Screen Key

Green to Transparency

Before Image

Green Background Color = OCF137

 After Image**

Threshold = 30.0%; Cutoff = 20%; Smoothing = None; No Check Mark Next To "Mask Only".

BLUE SCREEN KEY

Blue to Transparency

Before Image

Blue Background Color = 3AAFE6

After Image**

Threshold = 30.0%; Cutoff = 20 %; Smoothing = None; No Check Mark Next To "Mask Only"

COMMENTARY

Non Red Key appears to be an acceptable choice for replacement of Green Screen Key and Blue Screen Key whether the reason for using it relates to

a. keying out "green screens when you need to control blending, or when the Blue Screen or Green Screen Keys don’t produce satisfactory results"

and/or

b. you are a Premiere Elements Mac user whose choice of green screening tools is limited to Videomerge or Difference Matte because of the Windows Only nature of Chroma Key, Green Screen Key, and Blue Screen Key.

In this limited study, Green Screen Key and Blue Screen Key seemed to do better in keying out the green or blue between the webbing of the catcher's mitt. Fringing and control of it with Non Red Key needs to be investigated. Full Screen look were not as clean as wanted.

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* Study was done with Premiere Elements 13/13.1 on Windows 7 Professional SP1 64 bit. But, principles displayed in the study are expected to apply also to earlier versions of the programs (Mac and Windows).

**In Premiere Elements 13/13.1, keying effect was applied from fx Effects/Keying. Editing of the keying effect was done under Applied Effects Tab/Applied Effects Palette/Panel for keying effect expanded. Screenshots are from Edit area monitor displaying first frame of video. No Red Key Video sample is AVCHD.mp4 (1920 x 1080p30).

PE: Pan and Zoom/Time Remapping Excercise

INTRODUCTION

Recently a question came up about coordinating the times for the application of pan and zoom and slow/fast motion effects to the same video. There was no bug found in matching times seen in Time Remapping, Pan and Zoom Tool, or keyframing of Motion Scale for zoom and Motion Position for pan. What is seen is based on the principles of slow motion (frames are added) and fast motion (frames are subtracted) and what happens when pan and zoom is added to a video clip from Motion (no frames added) or Pan and Zoom Tool (frames added).

ISSUE

A Premiere Elements user ran into problems coordinating the timecode readings found going between workspaces of Expert, Pan and Zoom Tool, and Time Remapping in establishing a video effect where first and last sections of the video had fast motion, the middle section had slow motion and pan and zoom. What to do?

SOLUTION

The ISSUE presented was first addressed in the Expert workspace by keyframing of the Motion Scale for zoom for the middle section. Then the video was taken into the Time Remapping workspace where the slow and fast motion effects were applied. Although the Pan and Zoom Tool could be used to do the zoom, it was found easier to use the keyframing of the Motion Scale property for a video source.

Considerations and how to for interpreting timecodes between the workflows involved in this situation will be demonstrated by the example offered in the HOW TO to follow.

HOW TO 

STEP 1.  Strategy Planning

Expert workspace of Premiere Elements 13/13.1
Keyframing Motion Scale for Zoom and Motion Position for Pan
(Applied Effects/Tab/Applied Effects Palette/Motion Panel expanded and its Scale and Position properties)

Given a 40 second video clip on Video Track 1. This clip is a procession of children moving from left to right down a church aisle. The child of interest is seen in the middle of the screen in Edit area monitor at 17.533 seconds which is represented in Timeline timecode as 00;00;17;16. The goal is

(a) fast motion 2x and Scale 100% from beginning of the clip to just before the child begins to appear on screen
(b) 1/4x slow motion while the child is on screen and zoomed in
(c) fast motion 2x and Scale 100% immediately after the child moves out of sight

It is in this STEP 1 where the timing is defined which will impact the pan and zoom as well as the fast and slow motion effects in Time Remapping. In this example, it was decided from inspection of the Timeline content in Expert workspace and project goals that

(a) was going to be from 00;00;00;00 to 00;00;16;24
(b) was going to be from 00;00;16;25 to 00;00;18;02
(c) was going to be from 00;00;18;03 to 00;00;40;00

STEP 2. Creating The Pan* and Zoom Keyframing 

In the Edit area with the Timeline 40 seconds video clip selected, place the Timeline Indicator at 00;00;16;24. Refer to 1 and 2 in Figure 1.

With Timeline clip selected, go to Motion Panel expanded, click on Toggle Animation icon. Refer to Figure 1.

Figure 1. Pan And Zoom Using Keyframing Of Motion Scale For Zoom (In Expert Workspace Premiere Elements 13/13.1). To Get This Split Screen View Of the Motion Panel Expanded, Click On The "Show/Hide Keyframe Controls" Icon. In This Screenshot,"Toggle Animation" Has Not Been Activated Yet By Clicking On Its Icon.

Tap the right arrow key to move the Timeline Indicator to the right to a spot where the child just starts to be seen. Then move the Motion Scale slider from 100% to 140%.

Tap the right arrow key to move the Timeline Indicator to the right to a spot further along but not yet at where the child is in the middle of the frame. Move the Motion Scale slider to 183%

Tap the right arrow key to move the Timeline Indicator to the right to a spot where the child is in the middle of the frame. Move the Motion Scale slider to 214%.

Tap the right arrow key to move the Timeline Indicator to the right to where the child just goes out of sight. Move the Motion Scale slider to 100%.

STEP 3. Time Remapping Slow And Fast Motion Effects To  Step 2 Panned and Zoomed Video

Take the STEP 2 panned and zoomed clip into the Time Remapping workspace. Place the Time Zones as follows, but DO NOT apply the dots for the settings for fast and slow motion yet. At this point, the  Time Zones will be represented as

(a) Time Zone 1. 00;00;00;00 to 00;00;16;24
(b) Time Zone 2. 00;00;16;25 to 00;00;18;02
(c) Time Zone 3. 00;00;18;03 to 00;00;40;00

Now apply the 2x fast motion to (a) and (c) and the 1/4x slow motion to (b).

Record the new timecode readings that resulted because of the addition and subtraction of frames that took place when you added the slow and fast motion effects. The addition and subtraction of frames are not bugs but the basis for slow and fast motion effects wherever. The new readings will be (best possible to seconds level in the timecode hours;minutes; seconds;frames)

(a) Time Zone 1. 00;00;00;00 to 00;00;08;11
(b) Time Zone 2. 00;00;08;14 to 00;00;13;10
(c) Time Zone 3. 00;00;13;16 to 00;00;24;15

The child whose who was seen at mid frame originally at 00;00;17;16 is now seen mid frame at 00;00;11;07. And, these new timecode readings in the Time Remapping workspace will be the same when the Time Remapped clip is back in the Expert workspace. Keeping track of these timecode changes impacts instances when editing of the effect produced is going to be considered.

COMMENTARY**

The Pan and Zoom Tool can also be used to set the zoom for STEP 2. But use of the Pan and Zoom Tool requires special considerations for applying pan and zoom effect to video. Refer to
http://atr935.blogspot.com/2014/08/pe12121-pan-and-zoom-tool-and-video-file.html
It was found easier to use the keyframing of the Motion Scale and Motion Position properties for this purpose.


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 *Although Pan is used in description "Pan and Zoom", only Zoom was used in this example.

**Miscellaneous
When applying fast and slow motion using Time Remapping, the image that is shown in the monitor of the special Time Remapping workspace, the feature's monitor displays the Timeline content with prior edits that were done in the Expert workspace. In contrast, when you are applying pan and zoom with the Pan and Zoom Tool, the Pan and Zoom workspace monitor refers back to the unedited original Timeline import.






Work In Progress


ATR

PE: Alpha Adjust, What Is It?

INTRODUCTION*

Premiere Elements 4 through the current version (13/13.1) each have "Alpha Adjust" as a choice under its keying video effects. Never noticed it before. Then a Premiere Elements Mac user asked about "Alpha Adjust" as an alternative to Videomerge for green screen project. Premiere Elements Mac does not have the keying video effects of Green Screen Key, Blue Screen Key, and ChromaKey as does Premiere Elements Windows. And, so far the best alternative for Videomerge in Premiere Elements Mac has been found by many to be Difference Matte.

Alpha Adjust turns out to be an alternative for setting the Opacity that is found in Properties Palette  (version 10 and earlier) or Applied Effects Palette (version 11 and later). The Opacity found in either Properties Palette or Applied Effects Palette locations is referred to as a "Fixed Effect".**

Opacity applied as Opacity in Applied Effects Palette "Fixed Effect", See Figure 1.

Figure 1. Clip Opacity Applied Using Applied Effects Palette/Opacity Panel Expanded In Premiere Elements 13/13.1.

Opacity applied using Alpha Adjust keying video effect, See Figure 2

Figure 2. Alpha Adjust For Opacity Application To Clip In Premiere Elements 13/13.1 Fx Effects/Keying/Alpha Adjust.

The Alpha Adjust keying video effect includes controls for Ignore Alpha, Invert Alpha, and Mask Only. Both ways of adjusting clip Opacity appear to give the same result, but......

ISSUE

What is supposed to be gained using Opacity applied using the keying video effect named Alpha Adjust versus Opacity applied from Properties Palette or Applied Effect Palette?

SOLUTION 

Which Opacity to use depends on the rendering order wanted in Timeline or export.

The key points for deciding which Opacity to use....

• Rendering order (apparently in Timeline and in export) affects how opacity interacts with visual effects where the alpha channel indicates transparency

• The rendering order goes Video Effects first, the default panel options in Properties Palette or Applied Effects Palette next, and then alpha channel adjustments. And, there is a top to bottom ordering of the list in each of the these categories.

• According to this rendering order, Alpha Adjust/Opacity from fx Effects/Keying would be done before Opacity from Properties Palette or Applied Effects Palette.

• The Adobe recommendation is "If you want opacity to render earlier or later than certain effects, or if you want to control additional opacity options, apply the Alpha Adjust video effect".
  

The above key points on the use of Alpha Adjust can be found in the description in the Adobe Premiere Elements document on Effects Reference and the Adobe Premiere Pro document named "Adobe Premiere Pro Help / Compositing, alpha  channels, and adjusting clip opacity". Although the latter reference is targeted for Premiere Pro users, it is interesting reading for the Premiere Elements user. 

COMMENTARY

To answer the Premiere Elements Mac user's question about using Alpha Adjust for green screen effect.....No way is seen to use Alpha Adjust as a color key replacement for any of the program's green screening tools, such as ChromaKey, Green Screen Key, Difference Matte, or even Videomerge. However, Adobe writes

Alpha channel‑based keying effect

The Alpha Adjust Key effect lets you invert or turn off a clip’s alpha channel or convert areas without transparency to a mask.

But, that is all for clip once it has an alpha channel (transparency). The imported green screen video does not until color-based keying effect is applied to the clip.

Example....

Given clip with purple snow flake image on a solid green background. There is no transparency in that clip. If the clip is on the higher track, the whole image on this clip will be the only one seen.

Figure 3. Purple Snow Flake On Solid Green Background.

If the Alpha Adjust is applied to the clip in Figure 3, there is no way for Alpha Adjust to convert selectively the green to transparency leaving just the purple snow flake on a transparent background. However, the whole clip can be taken to total transparency by moving the Alpha Adjust Opacity slider to 0%.

If instead Green Screen Key is applied to the clip in Figure 3, the green color can be converted to transparency (represented by black) leaving just the purple snow flake. See Figure 4.

Figure 4. Green Screen Key Applied To Clip Shown In Figure 3.

When a plant background image is placed on a track directly below that of this purple snow flake surrounded by transparency, the image below will show through that transparent area in clip on the upper track and be seen.

Now, if the Alpha Adjust is applied to the clip which has had its green replaced with transparency using the Green Screen Key, the opportunity is gained to interpret the alpha channel (transparency where green color was) in the clip using the Alpha Adjust controls of Ignore Alpha, Invert Alpha, Mask Only.

Consider the example of this purple snow flake on its transparent background (from Green Screen Keying) on Video Track 2, and plant background image on Video Track 1. The following shows the effects of changing the Alpha Adjust controls at a fixed Alpha Adjust Opacity setting.

Alpha Adjust Opacity 100%, Ignore Alpha, Invert Alpha, and Mask Only options each Disabled.

Alpha Adjust Opacity 100%, Only "Ignore Alpha" Enabled

Alpha Adjust Opacity 100%, Only "Invert Alpha" Enabled

Alpha Adjust Opacity 100%, Only "Mask Only" Enabled

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*An offshoot of this study was going over the ways to export a Timeline content with transparency and maintain that transparency in the export. The following expands on our previous writings on this matter in the more recent versions of Premiere Elements.

An Example Given For Premiere Elements 13/13.1
Publish+Share
Computer
QuickTime
and under the Advanced Button/Video Tab of the preset selected, the essentials are:
Video Codec = Animation or PNG
No check mark next to Render at Maximum Depth
Depth = 32 bit

Publish+Share
Computer
AVI
and under the Advanced Button/Video Tab of the preset selected, the essentials are:
Video Codec = None
No check mark next to Render at Maximum Depth
Depth = 32 bit
 

**"Fixed Effect" details can be found in the Adobe document "Adobe Premiere Elements Help/Effects Basics".



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