forum.xda-developers.com/showpost.php?p=79775335&postcount=730

P3v12
For Android 9 (Pie) - Q Developer Preview issues are not addressed

P3v12_GoogleCamera_6.2.030.apk
Re-based the mod on 6.2.030 for the version with Time Lapse & included support for the Pixel 3a
Most settings from the previous APK were ported but some confusing or non-essential options were removed
Add option to enable 4k Time Lapse (thanks Arnova8G2)
Add Portrait Zoom setting to choose between Pixel 2/3 default (1.2x) or Pixel 3a default (2.0x)
Manual Exposure Slider & Manual ISO Slider are split into 2 options. Manual ISO remains 'experimental' in the sense it doesn't always use the ISO you specify. Manual Exposure Slider is for HDR+ Enhanced or Night Sight.
Added a Lib Loader by KoopahTManiac. It provides a faster and easier way to apply custom libs while reducing APK size. When you first launch GCam you may want to go to P3 Mod Settings>Custom Lib>Get Updates then choose a lib you want (Stock may be a good starting point). After the app restarts, go ahead and swipe it away from recents and this will stop the persistant message box until you change libs again.
Savitar ZA v2: Flatter tonemap, stock Noise Reduction, stock sharpness
Fi v2: Stock tonemap, reduced Noise Reduction, stock sharpness
Fi v4a: Flatter tonemap (Savitar ZA), reduced Noise Reduction, stock sharpness
I have not tested esz libs at this points
I would like to thank all contributors and people who have helped me thus far, and the testers!
Arnova8G2, back.rider, BSG, Charles_L, eszdman, fu24, KoopahTManiac, miniuser, namok, san1ty, savitar, scrubber, SerJo87, Toylan009, Urnyx05, xtrme

Q: "I already have a Pixel, why do I need to use a GCam mod?"
A: Here are the added benefits of Camera P3:
All Pixels:
Custom Lib options to reduce black crush, improve details, and/or increase clarity
Ability to choose 4K Time Lapse quality
Ability to choose zoom level in Portrait Mode of 1.2x or 2.0x (for the rear camera)
Ability to choose to enable HDR+ Enhanced for Portrait Mode
Option to have quicker access to Night Sight by "permanently" adding the little message at the bottom regardless of measured light (admittedly it disappears if you capture a photo in regular mode)
Option to increase shutter speed and frames in Night Sight for potentially "better" Night Sight photos
Option to disable the "Learning AWB" in HDR+ Enhanced/Night Sight
Option for manual shutter speed & ISO
Face warping is completely disabled
In addition to the above, these are the added features for specific devices (when compared to the stock app):
Pixel 1:
Portrait Mode (only when a "human face" is detected, does not work on objects/animals like Pixel 2, 3, 3a)
Removes the HDR+ mode reset on launch or when leaving settings
Synthetic Fill Flash (brightens faces when there is a strong backlight)
Motion Photos & Top Shot (if you have the correct Google Photos APK installed)
HEVC option
Photobooth
Adds focus button in Night Sight (Auto/Near/Far)
Tracking Autofocus in Photo mode
Super Res Zoom sharpening algorithm
Pixel 2:
"Learned Depth" for Portrait Mode which provides, usually, a more accurate depth detection and more pleasing bokeh
Synthetic Fill Flash (brightens faces when there is a strong backlight)
Top Shot (if you have the correct Google Photos APK installed)
HEVC option
Photobooth
Adds focus button in Night Sight (Auto/Near/Far)
Tracking Autofocus in Photo mode
Super Res Zoom sharpening algorithm
Pixel 3:
-Adds 60ps option to top bar in Video mode
Pixel 3a:
Synthetic Fill Flash (brightens faces when there is a strong backlight)