Ivan Galamian, in the Principles of Violin Playing and Teaching, said: The building of good intonation rests mainly on the sense of touch in combination with guidance of the ear.  The fingers are like blind people who guide themselves through a sightless existence by touching objects which mark their paths from place to place. [...] The hand learns gradually to orient itself, to find its proper location by the feel of the neck[...] From the hand position thus secured, the fingers in their turn learn to acquire, through their sense of touch the feeling for the correct placement and for proper stretch.  In this they are continually helped, guided and controlled by the ear.

I seriously doubt that any really good fiddle players look at their fingers for targets on the fingerboard.  However, I'll bet there are a lot of them that had to break the habit of trying. Specifically, those that once used finger tape.  As we all know, it is much harder to break a well-worn bad habit, than it is to acquire a shiny, brand new one.  I personally think that using finger tape is intentionally acquiring a bad habit, in an attempt to take a short cut through the long, difficult and sometimes tedious process that defines learning to play the fiddle. In the short-term, it really won't help with intonation, since the correct spot is so tiny that the eyes won't be of much use, and in the long-term will be detrimental to acquiring the muscle memory and ear required to reliably move your finger to the correct location and make the necessary rapid micro-adjustments to the pitch every single time a particular note is required. 

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Speaking of which the book Principles of Violin Playing and Teaching can be had (including shipping) for under $10 here at Amazon: <a href="