Hi,
I just finished a big batch of apatite analyses, the following is my routine for apatites in carbonatites and phonolites (so you may want/need other elements) on a JEOL 8900. Overall, I go with approach 2.
Analytical conditions: 15kV, 10 nA and a beam diameter of 15 µm
Element setup:
LDE1: F
PET: Ca, P, S, La, Ce, Cl
TAP: Si, Mg, Na, Sr
LIF: Fe, Mn
Counting times: 60/30 (Pk/bkgr) for F and Cl, 40/20 for Fe, all other 30/15
PFE specific settings:
Measurement options: TDI (but I only use it for F in the end; TDI also on the standards), Asynchronous mode, pick background position and models from a good wavescan
Analytical options: Halogen correction
I usually re-calibrate every six hours at least the apatite standard (Durango) to track any drift. I also carbon coat the standards together with the samples if possible.
Another good paper to read is also: Marks et al. 2012: The volatile inventory (F, Cl, Br, S, C) of magmatic apatite: An integrated analytical approach. Chemical Geology 291, 241 - 255.
I hope this helps. Enjoy your apatites!