Can you measure a dual angle drilling without using pro sect scale. Like if you don’t have one
If you are wanting to get a layout off a drilled ball, you could use a flexible tape and get the pin to pap, mb to pap and pin buffer measurement (assuming you have the pap marked and the vertical axis line to measure the pin buffer used). You then can plug those numbers into the above converter to get the dual angle layout.
If the PAP isn't marked then you'll have to locate it and mark the vertical axis line. Which can be done with a flexible tape if your careful and know what your doing.