Set a camera in quicktime using applescript - macos

Question

I know there is probably a very simple answer to this. I'm trying to setup an Applescript application that when activated will launch quicktime, open a new movie recording, set the camera and audio, start the recording and then end the recording and save it after 30 seconds.
I currently have a script that is doing everything except setting the camera and audio source. Any tips on how to select a certain camera and audio source using applescript?
Thanks!
Here is the code as it stands now..
--Set some Variables
--Max length of recording
set maxrec to 20 --in seconds
--Ending Message
set EndMsg to "Thank you for participating in this project. Your video has been recorded."
--Begin Loop
repeat
--Get the person's name
repeat
display dialog "What's your name?" default answer ""
set theName to (text returned of result)
if theName ≠ "" then exit repeat
end repeat
--Set the date
set theDate to current date
set y to text -4 thru -1 of ("0000" & (year of theDate))
set m to text -2 thru -1 of ("00" & ((month of theDate) as integer))
set d to text -2 thru -1 of ("00" & (day of theDate))
set h to text -2 thru -1 of ("00" & (hours of theDate))
set mm to text -2 thru -1 of ("00" & (minutes of theDate))
set dateStamp to (y & "-" & m & "-" & d & " " & h & mm as string)
--Create a folder for the person
tell application "Finder"
set p to path to movies folder from user domain
try
make new folder at p with properties {name:"Video Clips"}
end try
set p to (path to movies folder from user domain as text) & "Video Clips:"
make new folder at p with properties {name:dateStamp & " " & theName}
set thePath to result
--Establish the final name of the movie
set fileName to ((thePath as text) & dateStamp & ".mov" as string)
end tell
--Open New Recording, start and stop it
tell application "QuickTime Player"
set newMovieRecording to new movie recording
set windowID to id of first window whose name = "Movie Recording"
delay 2
tell newMovieRecording
--Set Camera to Blackmagic
set current camera of newMovieRecording to Blackmagic of video recording devices
start
end tell
set theSeconds to maxrec
repeat theSeconds times
display dialog theSeconds buttons {} giving up after 1 with title "REMAINING TIME"
set theSeconds to (theSeconds - 1)
end repeat
tell newMovieRecording
stop
end tell
--save and close the recording
set newMovieRecordingDoc to first document whose name = (get name of first window whose id = windowID)
tell newMovieRecordingDoc to save in fileName
set SavedRecordingDoc to first document whose name = (get name of first window whose id = windowID)
tell SavedRecordingDoc to close
quit
end tell
--Display "Thank You" Message
tell application "System Events" to set frontmost of process "Video Booth" to true
display dialog EndMsg giving up after 20 buttons {"Continue…"} ¬
default button 1
end repeat
Here is the error I get right now when I run it.
error "QuickTime Player got an error: Can’t make Blackmagic of every video recording device of document \"Movie Recording\" into type specifier." number -1700 from Blackmagic of every video recording device of document "Movie Recording" to specifier

Answer 1

use the current camera and current microphone properties of your movie recording object. Just replace item 1 with the appropriate device:
set current camera of recording to item 1 of video recording devices
set current microphone of recording to item 1 of audio recording devices

Answer 2

I had accomplished this by doing it manually
tell application "System Events" to tell process "QuickTime Player"
#To open dialog to show available cameras
click button 3 of window 1
#To select our device
click menu item "your_camera_name" of menu 1 of button 3 of window 1
end tell
With this the dialog will open and you will select your camera from the list...
Taken from another answer I made:
https://stackoverflow.com/a/45454785/3685973