A person with 'perfect pitch' doesn't have to first register C in their head. They just know the exact pitches of ALL 12 notes in the scale as well as the octave they fall in. In other words, if a person with perfect pitch were taken into a room with a piano (blind-folded), and you just play ONE note for them, they would be able to easily recognize & name the exact note you played. The method of registering C in your head first, and then mentally going up F is using 'relative pitch'.

My former voice coach, Judy Davis:
http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2001/01/31/MNL1260 03.DTL

had me purchase a 'pitch fork' tuned to concert A or C & carry it around and listen to as many times during the day. To this day, even though I don't have perfect pitch, I do have concert A & C pitch solidly in my head now, and can identify any other (12 semi-tone) notes of a scale by recognizing the interval relationships between C & other note(s) heard. This method of pitch recognition is referred to as: 'Relative Pitch' recognition, and important skill that ALL musicians need to develop. Tommy, whether you have perfect pitch or use relative pitch skills, pitch recognition is an essential skill that ALL musicians need to learn and to keep honed. - Scott. Here are the basic intervals that all musicians should be able to easily recognize (both ascending & decending):

Unison
Minor 2nd
Major 2nd
Minor 3rd
Major 3rd
Perfect 4th
Tritone (flatted fifth or augmented 4th)
Perfect 5th
Minor 6th
Major 6th
Minor 7th
Major 7th
Octave


To help with interval memorization, here's a link to songs that contain these intervals (first two notes of the melody):
http://www.people.vcu.edu/~bhammel/theory/resources/macgamut_theory/songs_interval_recognize.html

Have fun.


Scott