CTF Correction in EMAN1
EMAN's model was outlined in the [attachment:EMAN1999Ludtke.pdf 1999 paper introducing EMAN]
This model was confirmed accurate with experimental data in the [attachment:GroEL2001Ludtke.pdf 2001 paper on GroEL at 11.5 A resolution]
The derivation of EMAN's CTF correction model was in [attachment:CTFIEEELudtke.pdf a rather obscure IEEE proceedings paper]
Finally, you can the updated details from the 1999 paper in [http://blake.bcm.tmc.edu/eman/eman1/ctfc/ctfc.html the static EMAN1 documentation]
EMAN2 is going to use a new model for easier CTF correction...