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Thank you 👍
One last question, it is difficult to measure exactly 3.67 meters, what is the best a bit longer or a bit shorter of the magic number?

It is completely unnecessary to measure the distance that accurately. If you are taking photos of the sky and there is nothing of interest in the foreground very close to you, you can pick any object, say, tens of meters away in case the hyperfocal distance is 3.67 m that your camera is capable of focusing on. For practical purposes, if you're shooting distant objects, the hyperfocal distance is actually just the lower bound of the distance at which you must focus for your objects to be in sharp focus.

That's great, good to know before next mission.🙂👍