Before I keep forgetting to put this here for you:
You can measure your screen distance once properly, and then set yourself up a little system to keep track of changes in distance. As per a great post in our group:

There you go.
There’s also plenty more on measuring, over in the wiki.
For a million more tricks and ‘shortcuts’ (there are no shortcuts) and helpful insights and community, support endmyopia with one of our awesome courses.
Cheers,
-Jake
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