Finger Height

Q: What is your recommendation for finger height during playing? 
I have searched your site but haven’t found the answer (it may be there and I missed it). 
I wasn’t sure if they should be ON the keys or just slightly above? 
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Update Dec. 31st, 2019:
I found a masterclass video showing excessive height in RH fingers: (video)




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Jen's original answer:

Good question.
There is some small controversy about finger height, and I should probably write an article about it.
In my experience I notice two realities:

1. During very fast playing, the fingers remain (almost) touching the key tops when the fingers are "up"
2. During all playing, your finger exchanges are much smoother (C to D; or G# to A) when all fingers are at the same distance from their keys, so they can all act in exacting unison.

Here are some of the problems that lead to misconceptions:

a - Clarinetists do not seem to have the same notion of finger height as flutists; they may be heard to say that if the finger hovers in the way of the hole letting the air escape, the tone quality is affected by the finger's height. This is not true on flute, since there are no holes that do not have keys already hovering equidistant above each chimney.

b - When flutists demonstrate flute fingerings, we necessarily lift all fingers that are "off" very high, away from the keys the flute, to show someone else which fingers remain "down". We do this from the very first moment of teaching the flute to a beginner, so beginners only see their hands with this image in mind, and then put their arms out of sight, and "imitate the fingering they just saw". This leads to the student having bizarre looking fingers held away from the instrument, because that is the last sight they saw. Think about this when you demonstrate fingerings: Show both ways: with fingers on keytops, and with fingers pulled away. Make sure the person learning understand the difference.

c - Flutists can only see their hands in two conditions: While holding their flute in front of them like a clarinet (not blowing it), and watching their fingers move and when playing IN THE MIRROR to watch what they are actually doing with their hands.

After weeks/months/years of avoiding the instruction "use a mirror when you play" or "video-record yourself and watch to see what you're doing", most students correct almost all their posture-hand-finger-arm-head problems when they actually do look in the mirror while practicing. The changes are instant because they have seen it with their own eyes.

d - Finger movement is affected by how the flute balances in the hands. If the flute bobbles when all fingers come off (D to C#) and actually rocks in space, the problem is NOT finger height. This is a multifaceted problem called "hand balance when holding the flute". It is corrected by starting with the chin-plate's coverage, the angle of the headjoint to the keys, the curve of the "hinge" of the left index finger knuckle under the flute on the left, and the use of pressure forward of the right thumb on the body of the flute.
Go to this article here, if  flute stability in the hands is your area of difficulty.

Fingers can become low and curved once balance of the whole instrument between the two hands is solved. (Debost writes on this too.)

e - Finger height is dependent on the speed of the note changes. In a slow pace of note changes, you may not hear any ill effects of different finger heights, and you may have loads of time to bring down a finger in preparation for a fingering (ie: Emmanuel Pahud uses very high finger heights for no particular reason I've every heard explained; I call it expressive!). If you watch a bunch of videos of professionals, gauge their finger height, shape and movement when they are playing super fast sixteenths and thirty-seconds. Slow down the film and look at the shape and movement of their hands. They are like curved paws that almost never leave their keys.
See photos at top taken from videos.

Hope this helps.
Comments welcome!

Best, Jen speedtypin' on first coffee