There is no such thing as one correct placement of any finger on the violin, since every note we play is in a context, and the context is always changing. If we are playing in E major we usually like our 1st finger B high enough to agree with the open E-string, however when playing in D major the 1st finger B will be flatter, in tune with the open D-string below.
The placement of the finger will change again if we are playing a high raised 7th, for instance in the key of C minor.
So the finger needs to be available to move, to adjust however minutely to each new intonation scenario that comes along.
At times we need to compromise for instance when playing the arpeggiated chord in the Mendelssohn cadenza (bar 339) of open G, E on the D-string, B on the A-string and open E. The 1st finger scale degree here has to make a compromise between tuning high to the E-string and low to the G-string.
Intonation - Introduction
- for Harmonic and Melodic (expressive) intonation
- for Concerto in E minor by Mendelssohn