sjavery

I should have added that if you want to make dawn flats, you cannot just add this on to the end of a normal sequence. After the normal imaging sequence has finished, Sequence will close the roof. It will not automatically re-open the roof even if the dawn flats box is checked. Therefore, if you want to avoid a roof collision you need to wake up in time to open the roof manually! Stephen

Having retired at the end of 2013, I decided I needed a new hobby, so installed (with the help of Rupert from Astrograph) a new ASA system at the E-Eye facility near Fregenal de la Sierra, Spain. The system comprises an ASA400 F8 RC scope having a native focal length of 3200mm, fitted with a 0.69x reducer, converting the system to 2208mm/F5.52. The scope is supported on an ASA DDM85 Premium mount with an ASA bent pier. My camera is a Moravian G4-16803C1 with KAF-16803 sensor, and has a Moravian EFW-4L-7 50mmx50mm filter wheel equipped with a set of Astronomik filters: a deep sky RGB set and 6nm Ha, SII and OIII NB filters. I am running ASA's own software: Sequence, Autoslew, Autofocus, coupled with Maxim DL for camera control. The hardware comprises a small PC running Windows 10, a Dragonfly, and an AAG Cloudwatcher. Accordingly, the system is fully remotely controlled from my home in Sussex, UK. My main interest is in deep sky astrophotography. I am processing my data using PixInsight. As might be expected with a relatively complex new system, there were a few teething problems, but now everything works very well and gives excellent results.

I regularly use Sequence to make Dusk flats. It works well if you know what to do. A few points worth noting: 1. As soon as you check the "make dusk flats" box, a window will pop up asking for the configuration file which should be used (and which you must have set up previously). If the sun angle has reached 0 degrees, the scope will start to slew immediately after you select the configuration file. Therefore, you need to open the roof before selecting the file! Sequence does not automatically open the roof in this mode (for some strange reason....). 2. The START @TIME and RUN NOW keys play no part in taking flats. As already stated, the scope will start to slew as soon as the dawn flats box is checked, the config file is selected, and the sun has reached 0 degrees. (It would help if this was stated in the User Manual!) 3. The configuration file is set up under the settings window. The exact parameters will obviously depend on what filters are installed. In my case, I have L,R,G,B,OIII,Ha,SII. I find that for dusk flats the correct order is SII,Ha,OIII,R,G,B,L and the opposite for dawn flats of course. My NB filters are 6 nm. I find that if I set 5 flat exposures per filter the timing works well and I get a full set of flats. 4. Using a front illuminated CCD, RBI may be an issue. If you normally use pre-flash, you should turn it off for sky flats and then use dark optimisation for calibrating the flats. At least, that works for me. Stephen