Updating "Date Created" after copying files - windows

Question

I have recently used iCloud for Windows (10) to download all pictures from iCloud onto my local machine. I then wanted to create a backup so I copy-pasted all (15'000) pictures onto an external hard disk.
I noticed that because of the copy-paste action, the "Date Created" has -- in hindsight obviously -- been changed from the date that the picture was taken to the date / time of the copy action.
Since the copy-action and before I noticed the change of date, I have put many hours into putting pictures in subfolders, etc. I would now like to put the original date/time back into the metadata.
My idea is to make a dirlisting of the iCloud original archive, returning filename, md5 hash, and Date Created. I then want to write a script (Powershell?) to find the matching file in my subfolders, and update the date.
A few questions:
Does this seem like the best approach?
Is there a better way to copy photo's in the future, keeping the original Date Created?
Any help into the right direction whether this is a good idea with Powershell, would be greatly appreciated.

Answer 1

Manually changing timestamps using PowerShell
To change the Date Created, Date Modified, and Date Accessed file properties using PowerShell, I'd recommend checking out this website here. It explains how to change the Date Created/Modified/Accessed file properties for a single file, for all files in a given folder, or even for a folder itself. For example:
For a single file:
To set the date created time for "filename.txt" to 5 December 2012 at, say, 9:57:05 PM, you'd write:
(Get-Item "C:\Users\Path_to_file\filename.txt").creationtime=$(Get-Date "05/12/2012 21:57:05")
Similarly, to set the date modified, you'd write:
(Get-Item "C:\Users\Path_to_file\filename.txt").lastwritetime=$(Get-Date "05/12/2012 21:57:05")
and for date accessed time:
(Get-Item "C:\Users\Path_to_file\filename.txt").lastaccesstime=$(Get-Date "05/12/2012 21:57:05")
You can event set properties to other properties. For example:
To set the date created equal to the date modified, you'd write:
(Get-Item "C:\Users\Path_to_file\filename.txt").creationtime=$(Get-Item "C:\Users\Path_to_file\filename.txt").lastwritetime
For all files in a folder named "Test":
Get-ChildItem -force 'C:\Users\Path_to_folder\Test\' * | ForEach-Object{$_.CreationTime = ("3 August 2019 17:00:00")}
Get-ChildItem -force 'C:\Users\Path_to_folder\Test\' * | ForEach-Object{$_.LastWriteTime = ("3 August 2019 17:10:00")}
Get-ChildItem -force 'C:\Users\Path_to_folder\Test\' * | ForEach-Object{$_.LastAccessTime = ("3 August 2019 17:10:00")}
Note that the -force parameter ensures that hidden files are also included. Also, keep in mind that if you want to change each picture's timestamps to that of its own corresponding image (i.e, if you want to intelligently automate the process), you'll need to write a script that takes care of each separate case.
Copy files while preserving timestamps (and more)
The simplest tool to use is Windows' own, built-in tool: robocopy. See Microsoft's documentation on the robocopy command here. You just run the program via the command prompt (with administrator privileges).
For your needs, suppose you have images and videos in their original form (the ones that have all the correct timestamps, etc.) in the folder "Original", located at "C:\Users\Person\Desktop\Original", and you'd like to copy all those images and videos to a folder located on your external hard drive, at "D:\Pictures\Copied". The following command would probably work best:
robocopy "C:\Users\Person\Desktop\Original" "D:\Pictures\Copied" *.* /e /copy:DAT /dcopy:DAT /mt:16 /j /xjd /xa:s /r:1 /w:0 /log:"filename_path.txt"
Each argument is explained in detail on Microsoft's documentation page for robocopy, but I'll explain them here too.
The 1st argument specifies the path to the source folder. Please note that there are no trailing backslashes! If you include a backslash at the end, robocopy won't understand the input.
The 2nd argument specifies the path to the destination folder.
The 3rd argument can actually be multiple arguments. Here, the *.* specifies the file or files to be copied. Since wildcard characters (* or ?) are supported, *.* matches all files in the source directory (i.e., everything will be copied). *.* is the default parameter, so if you want all files to be copied, you don't even need to specify this parameter. If you want to copy, say, all files that end in .jpg, you'd write *.jpg. Or, if you want to copy, say, just two files file1.jpg and file2.mp4, you'd write those out explicitly, one after each other, as such robocopy "C:\Users\Person\Desktop\Original" "D:\Pictures\Copied" file1.jpg file2.mp4 /e /copy:DAT /dcopy:DAT /mt:16 /j /xjd /xa:s /r:1 /w:0 /log:"filename_path.txt".
The 4th argument /e copies subdirectories. This option automatically includes empty directories.
/copy:DAT specifies which file properties to copy. Here, D, A, and T means that the file's Data, Attributes, and Time Stamps properties will be copied. Refer to robocopy's documentation for more details.
/dcopy:DAT same as /copy:DAT except for folders.
/mt:16 creates multi-threaded copies with 16 threads. You can specify an integer between 1 and 128.
/j copies using unbuffered I/O (recommended for large files).
/xjd excludes junction points for directories.
/xa:s excludes "System" files.
/r:1 specifies the number of retries on failed copies. Here, it's set to 1. The default value is 1,000,000 (one million retries)!
/w:0 specifies the wait time between retries, in seconds. Here, it's set to 0, so 0 seconds are spent waiting.
/log:"filename_path.txt" writes the status output to the log file.