Hello Michael and Francois,
I have just managed to gather further results (Ca II triplet + O I 8446 region, but O I 7774-76 was left off, my ccd is not enough large), so let me extend this collection with further - mainly - symbiotics:
- Changes to Michael Verlinden's AG Peg
My resolution was typically R~2700 (35 micron slit, LHires III + 600/mm Vis + Orange wratten filter directly on top of the ccd), lower than Michael's R~3688.
BF Cyg was suffered by defocus both (R~2200):
Vend47 is starting to show the Paschen end:
And, the one I was most curious (only 5 x 10 minute, of last covered by veily clouds):
v694 looks to be a good school example to see how the CaII and Paschen end overlap (the notation of H I .... and P 12,13 brought from VSpec via copy/paste), here all in emission.
The only unusual, that all the Balmer serie rather wide (like 500 km/s half width), but Paschen and CaII are so thin that here unresolved (R~2700). Possibly they are part of the outer nebula.
In contrast with BF Cyg, where these lines also play some role.
And finally, an experiment of b Per just to speculate where the 3rd star could show any mark:
However in this b Per case (as most common), the Paschen is showing similar characteristics as Balmer.
To have this material accessible at one place, attaching the zip of my results.
The outcome of my analysis, so far AG Peg and BF Cyg may be worth to followup (BF Cyg in poor quality, due to SNR and Paschen contamination), and rarely (upon special events) all the other stars, otherwise just redo rarely.
I also speculate, that in case we want to setup followups, we may need to have absolute flux (continuum is very hard to determine, and lack of I band observations - better just to select the feature as-is with absolute flux for a simple integration) - however, MILES typically ends at 7400A so any advice appreciated how to gain IR flux!
Cheers,
Peter