Q1: What is an ICC profile?
A1: https://en.wikipedia.org/wiki/ICC_profile

Q2: How do I make one?
A2:

1. Get an RF IT8.7 target from http://targets.coloraid.de/

2. Scan it at 300dpi 24bit color tif

3. Crop image to the black bars, like this: https://fumovite.hen.usbx.me/filebrowser/api/public/dl/Dlp6XaOP?inline=true

4. Download Argyll from https://www.argyllcms.com/downloadwin.html (Documentation if you want to look through it: https://www.argyllcms.com/doc/ArgyllDoc.html)

5. Extract the zip and add the binaries to Windows' path. If you do not want to add the binaries, skip 5.1 to 5.7, but you always need to move into the bin directory of Argyll to use it. See steps 5.a to 5.c

    Add binaries to path
    5.1 Move the extracted Argyll_Vesion folder to, for example, C:\Tools\
           The folder structure should look like this after moving : C:\Tools\Argyll_V3.2.0
    5.2 Use the Windows search to find "Edit the system environment variables" and open it
    5.3 Click on "Environment Variables..."
    5.4 Find the "Path" variable under "system variables"
    5.5 Click on it, then click Edit
    5.6 Double-click on an empty space and add the path to the Argyll bin directory. Confirm with OK once done
    5.7 Confirm all system properties in Windows by clicking OK
        Now you can run Argyll commands from anywhere using CMD or PowerShell

    Move into bin directory
    5.a After extracting the zip, open a CMD or PowerShell window
    5.b Use the command cd to move into the bin directory of Argyll, for example: "cd C:\Users\User\Downloads\Argyll_V3.3.0\bin"
    5.c Now you can run the binaries by typing their name

6. Open a CMD or PowerShell window (Ignore this step if you followed 5.a to 5.c)

7. Run the following command. Replace the values with what is needed

scanin -v -dipn "C:\Users\User\Downloads\scans\canon.tif" "C:\Tools\Argyll_V3.3.0\ref\it8Wolf.cht" "C:\Users\User\Downloads\Extras\R231102W.TXT"

    scanin  - command from argyll, conerts tif scan to ti3 device value file
    -v      - *v*erbose, shows progress / what it does
    -dipn   - generates *d*iagnostic output, the i stands for some black white magic fuckery IDK, p marks the *p*ixle areas sampled, n adds the sample box *n*ames
    Path to your cropped scan of the target
    Path to the it8Wolf.cht file, located in \Argyll_V3.3.0\ref
    Path to the .txt reference file of your charge. It is included on the CD, and can be downloaded on http://targets.coloraid.de/ when scrolling down. Make sure to pick the one with the same name as your charge number, which can be found at the bottom right of the target, and which includes the W at the End

    If you get any errors, fix them

    This created a .ti3 file in the same directory as your .tif scan and a diagnostic image in the bin directory of Argyll. If anything is wrong in the next steps, check the diagnostic image to see if anything seems off

8. Run the following command. This can take time. It took around 5 minutes for me. Make sure to press enter every now and then cause windows terminal likes to freeze for no reason

colprof -v -D"canon" -qh -aX "C:\Users\User\Downloads\scans\canon"

    colprof - Creates a ICC Profile from .ti3 data files
    -v      - *v*erbose, shows progress / what it does
    -D""    - *D*escription, add whatever you like
    -qh     - *Q*uality setting, *H*igh. Available are ql, qm, qh and qu, for low, medium, high and ultra. Ultra makes absolutely no difference for me when it comes to colors, apart from taking like 40 minutes to finish, compared to 5 at high
    -aX     - *A*lgorithm used, the X uses display XYZ cLUT + matrix, which seems to be the recommended one (From what i found?)
    Path to .ti3 file, WITHOUT extension

If it fails with "-aX", use "-as". Seems to slightly worse results but supposedly failproof

9. Now you have a .icc profile in the folder where your scan and ti3 file is uwu