This guide includes step by step instructions on how to use a HEX editor to modify the game files to support your aspect ratio of choice. It also contains a FOV fix and how to unlock the framerate cap.

I have been waiting a long time to find a fix for this game as it was the only thing keeping my from really getting into it. I finally came across a post by "LIKE TV SHOW" who may or may not have discovered this fix here.
https://gtm.steamproxy.vip/app/287700/discussions/0/1762481957304931257/
Unfortunately the post is lacking in how you actually go about applying the fix which inspired me to put together a proper guide that actually works with the current version of the game. I play on 3440x1440 ultrawide 120Hz monitor and it is Glorious!

First you will need to have a HEX editor if you don't already.
I personally like HxD which you can download here[mh-nexus.de].

Download this FOV fix from github MGSV-TPP-FoV repository courtesy of "Will mon".
https://github.com/AltimorTASDK/MGSV-TPP-FoV/files/2237953/fov_for_114.zip

STEP 1
Start by running HxD or what have you.

STEP 2
Click "File" and "Open"
Here you need to find the game folder in your steam library.
Mine looks like this. "\Steam Library\steamapps\common\MGS_TPP"
From the game folder you need to select the "mgsvtpp".
You should now see colums of hex values.
Do not select "mgsvtpp.exe.bak" as I have no idea if editing that file will have the same results.
Reference this screenshot to verify that your game is the correct version and you have selected the correct file to HEX edit.

STEP 3
Press "CTRL F" to open the search window.
Select the "Hex-values" tab and click "All" under "Search direction".
Search for the hex value "39 8E E3 3F" which is the value for a 16:9 aspect ratio.
"39 8E E3 3F" is found in three locations.

First HEX edit should look like this once complete. This example is for 3440 x 1440.


The second HEX edit should look like this once complete.


The third HEX edit should look like this once complete.
You can verify you have found the correct locations by looking at the Offset(h) column on the left.
Once the value has been entered the Single(float32) value will change on the right.
All 3 need to be changed to the value that matches your desired aspect ratio.
In order to find the other 2 locations you may have to select "Forward" under "Search direction".
If for some reason your desired aspect ratio is not below just leave a comment with your desired resolution. I will add it for you.

STEP 4
Once you have changed the HEX values at all 3 locations click on "File" and "Save".

5:4 - 00 00 A0 3F
4:3 - AB AA AA 3F
3:2 - 00 00 C0 3F
16:10 - CD CC CC 3F
15:9 - 55 55 D5 3F
16:9 - 39 8E E3 3F
1.85:1 - CD CC EC 3F
2.39:1 - C3 F5 18 40
2.76:1 - D7 A3 30 40
3x5:4 - 00 00 70 40
3x4:3 - 00 00 80 40
3x16:10 - 9A 99 99 40
3x15:9 - 00 00 A0 40
3x16:9 - AB AA AA 40
21:9 (2560x1080) - 26 B4 17 40
21:9 (3440x1440) - 8E E3 18 40
21:9 (3840x1600) - 9A 99 19 40
32:9 - 39 8E 63 40
32:10 - CD CC 4C 40

STEP 1
Extract the the zip file that you downloaded from Github to the main game folder here.
\steamapps\common\MGS_TPP
Alternatively you can extract the zip file anywhere you would like to keep it.
Then copy the ".dll" and ".cfg" files to the game folder.
STEP 2
Change FOV in fov.cfg which you extracted to the main game folder.
The FOV fix defaults to 125.

Note: The files in this fix were designed for version 1.14 of the game but they seem to work just fine with version 1.15.

STEP 1
Open the program files folder where you installed steam and look for the following.
\Program Files (x86)\Steam\userdata\79795185\287700\local
Note: The second to last number "79795185" is unique to my Steam profile. Everyone should see a different number than mine.

STEP 2
Open TPP_GRAPHICS_CONFIG with notepad.
Alternately you can run a file search for "TPP_GRAPHICS_CONFIG" on the same drive you have Steam installed.

STEP 3
Look for the line "framerate_control" : "Auto"
Change it from "Auto" to "Variable"
Now save changes.

STEP 4
Right click on TPP_GRAPHICS_CONFIG and select "properties".
Check the box that says read only. This will make sure the game doesn't revert the changes.

Note: Unlocking the framerate will only work if you have V-sync turned off in the game settings otherwise you will only see a max of 60 fps.

The following screenshots are 3440x1440 (21:9) with a FOV of 110.

Title Screen

Cutscenes & Cinematics



Standing

Crouching

Crouched Aiming

Prone

Prone hidden

Horseback

I am aware that there is an issue with the markers moving around funny when using an aspect ratio other than 16:9. This is not game breaking or immersion breaking for me so I doubt I will be putting much effort into finding a solution.So far I can only find cheat engine tables. If anyone has any ideas besides cheat engine let me know.

I would like to give a special thanks to the people that helped make this guide possible.
"LIKE TV SHOW" for possibly finding the latest hex edit.
Will "mon" for the latest FOV fix
and"SMX87"for being a royal pain in my side because he loves MGSV that much!

This is how MGSV was meant to be played!