spectro-aras.com

Thank you Joan and Francois, I will prepare a series graph then.
So far we have only 3, big question if someone could do a 4th some more days later (I'm a weekend observer).

All the best,
Peter

It was a very hard capture this time, for various reasons: The object was very low in the end, had breaks for technical difficulties (usb moved, focus shift) and this is a sum of all the 3 parts.

Simbad didn't find A0535+262 just "HD 245770" or "AO 0535+26" at similar position and mag 9.5. Yesterday I did a 3 x 5 minute series (ref: 125 tau), and 5 hours later made 8 x 5 minutes series (ref: 136 tau), curious if I can find variabilities. _hd245770_20150207_686_917_psomogy...

It was an edge case to guide on slit (1.5 sec) from which I'd estimate between 11.5 - 12 mag:

I also tried it but clouds came (2 x 30 min succeeded only), dependent on cosmic rays removal:
At least the SNR can be read visually.
AAVSO tells it was around 13 mag.
Ref.star: HD 53609

Updated firmware (3.42 -> 3.44, got from support telling this is a known issue been fixed) solved the problem completely! (Right before I checked the lines are still there, so it was definitely the upgrade.) Uploaded now the proof of the fix (median filter of flat - flat). flat_after_upgrade.png I t...

Francois, not much data in aavso yet, looking at more days LCG generator it must have fallen quickly towards 12.8 mag.
I expect more data should be available soon by local variable observers.

Thank you Olivier for the help, I will adjust to the dust line before next observation and will do a retry. This time the vertical gain correction did not help, maybe I will give a try it on the next session. The SNR should be already good, taken 21 flats (8 sec) + 15 bias + 21 flat-darks with expos...

Robin,

I've created new topic on 414EXM now and put there some material.

Flat produced by ISIS, normal view, it is quite ordinary I think: flat_isis_atik414exm.png Having enlarged the dynamics (see bars for interval, linear), you can see the strange column pairs: flat_problem.png To make visible all, I did a box median [11 x 1] and deducted the flat itself: flat_problem_...