Twilight Flats


#1

I would like to hear from anyone who uses SGP for twilight flats. I get the distinct impression, based on my initial tries, that the Wizards are more suited for light panels, but I might be wrong based on my initial trial. My thought is to set up a sequence with flats, but before filling out any exposure values use frame and focus to determine exposure, then run one series (say my B-filter), pause, figure out the exposure for the next filter (say V-filter), then proceed. My motivation for not using a panel is that I need flats for a near-IR filter and my EL panel emits very little in the near-IR spectrum. IFY, this is for a remotely controlled observatory.
Thanks, Ed


#2

When I do twilight flats, I do frame and focus until I get the adu I want for each filter, then keep the sequence window open and increase the exposure as needed (mostly for Sii Ha Oiii).

If one were so inclined, they could probably calculate a sky brightness level gradient to set up the sequence as targets for each filter, then events with different exposure times. I’ve never tried this. Because taking 10 flats each for 7 filters isnt that big of deal so might as well do them manually.


#3

Thanks for the reply, that sounds like a good strategy to me and I will try it next opportunity.
Ed


www.mainsequencesoftware.com