If you just want Sky Trak game to display in 4:3 on a 1080P display. Since the game does not let you specify a specific full screen resolution we found this method to force it into 4:3 aspect ratio. I would recommend you do this while actually in the game itself and not the menus as the game HUD/info seems to be cropped/trimmed as you resize the window.
- Launch SkyTrak and press Alt+Enter.
- Drag/resize the SkyTrak game window in an approximate 4:3 square shape
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3.Press Alt+Enter again to full screen SkyTrak which should now keep the aspect ratio previously set.
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If you want to have all windows applications to be forced to a 4:3 resolution (not ideal if connecting a second 1080P monitor/TV)
- We used Custom Resolution Utility by Toastyx (1.4.2) to add a custom 4:3 resolution. (https://www.monitortests.com/forum/Thread-Custom-Resolution-Utility-CRU)
- Once installed we used it to set a resolution of 1400x1050.
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Hope this helps.