Most of my students, find drawind the hands more challenging than drawing the face! Here are some of the basic lines and mesurements to help you study the hand, as we see them in our iconography courses. I hope you will find it usefull. Any questions, opinions and suggestions are welcome as they help me improve, so I am leaving the comments open for you!
Εδώ θα βρείτε το μάθημα στα Ελληνικά.
Arhontia Karakosta Iconography 
Hello, I have never really measured the angles. I don’t think of it as an exact science like geometry, I do it mostly “by the eye” as we say here in Greece. Mayby you could print my sketch, and measure yourself anything you feel necessary to help you.
Very clear and precise.
Thank you for sharing your skills!
Very kind of you!!!
Very good! Thankyou
Hello
Can you provide the angles between fingers in the blessing hands sketch?