Hi Nick, Andy,
I should log on more often!
My last attempt with V392 Per was on 6th – very dim and almost swallowed in twilight. Low altitude meant that I had nearly 50% of the ‘scope’s aperture obstructed by the bottom of the shutter of my observatory too. I feel fortunate that I got any kind of image as I could only detect the faintest ghost in the guide camera image and it was more luck than judgement getting any light from this object through the slit. Only the Ha complex was detectable, but it is and here is the result, alongside the rest in an Excel normalised stack.
Andy, Thanks for the tip about verifying response curves. I need to work at this aspect a bit more. I’m sure I am not getting atmospheric bands out well – the BASS method of picking and spline fitting to smooth an initial response curve doesn’t get the detail of these for me (and tends to become unstable when I try).
The above graph is normalised and plotted so that the pedestals either side of the Ha peak are 10 units apart and the Ha central peak is 100 units relative to the pedestals. It seemed easier to do this in Excel than in BASS, but I don’t end up with a set of spectra I can submit. I need to get to grips with the BASS way of doing this (I think I understand the basics of how to do it). Indeed one of my next tasks is to read up about preparing spectra for submission to e.g. the BAA database.
Cheers,
John Savage