More accurate measurement method
I haven’t tried this yet due to lack of privacy, but it should work.
Tools:
door that opens
sheet of paper
tape
pencil
Open the door and tape the paper on one side at dick level. Mark the paper which edge is up, and also make a small mark on the door so you can later place the paper in the same spot.
Stand with your belly against the doorknob side of the door. Note your foot placement and anything else that will help you to position yourself exactly the same next time you do this.
Stretch your dick out and work down gradually as you kegel checking for LOT. When you find it, mark the paper at the end of your dick. Take the paper off, measure the angle if you like, and tuck it away for future reference.
Next time you want to check LOT, tape the paper on the door lined up with the mark and repeat.
Edit: Of course, this would also work taping the paper on a wall next to a door jamb, or even on the side of a refrigerator. Be creative.