Camera Interface 5.43

[Forum_2015]

Hello everybody,
a new camera interface is available at the Astroart web site: http://www.msb-astroart.com/

Version 5.43 - August 11, 2015
-------------------------------

* Sorting of object coordinates using a shortest path algorithm.
* Improved precision of deepsky coordinates.
* Plate-solved centering with option for JNow.
* Script command FindCoordinates with custom field size.

The object list can be sorted from the context menu in the "GOTO" page of the Telescope Window, or using the script command Telescope.List.Sort
The algorithm choosen is a "shortest path", modified for starting from lower RA to higher RA. The result you can expect is something like:

P.S.
Until now, which software would you use to sort a list of objects in equatorial coordinates for shortest telescope path? I know that some users did it by hand, because they didn't find a suitable utility or planetarium with a such function.

[Forum_2015]

Fabio,

For me the last three of the 4 items in your list are great. However, the sorting issue is a complex one. If you are doing long exposures, say RGB or LRGB then sorting them does not necessarily give you a good plan for a nights observing as it does not take exposure time into account. This is why I wrote the "plan simulator" into Observation Manager. But for very short exposures done manually it will be a good solution. Before I had the simulator software built in I would often find that mid RGB say 4 x 300sec exposures there would be a meridian flip or reach scope meridian limits. In my case with a very variable horizon the star or galaxy could go behind a chimney, power pole or a tree!
I like to be able to create a plan for the nights observations, run the simulator with a start time and check that I have all the targets in view with no flips and not close to horizon obstructions taking long exposure times, settle times, filter changes, plate solves and actual scope movement times into account. That way I only have to worry about the cloud sensor or lost guide alarm.
I still have the ability to change the sequence to get the most critical targets in the best part of the sky. Sometimes this means a complete slew 180 degrees and then back again.
I have not automated this process of target planning in Observation Manager 9.08 and I am not sure it is practical to do so.

By the way item 4 the new FindCoordinates custom field size is just fantastic for setting up your scope accurately. As long as you can initially set it up to within a few degrees I now have a script to give you audio instructions to adjust the mount. Great feature. I still think AA5 has the best and fastest Plate Solve of any software!

All the best

John
@astrojohn
http://www.astro.me.uk

[Forum_2015]

Fabio,
thanks for the 5.43 interface, really big improvements. BTW object minimum-path sorting was in my to-do list and you solved my problem in advance.
Coming to the observation plan I solved the problem of objects visibility adding to my auto-image script azimuth and elevation limits active when scanning the object list. In other words I set a sort of rectangle in the sky where imaging is allowed; if the object coming from the list scan is inside the rectangle imaging can start, otherwise the object is (temporarely) discarded (but tested again at the end of the current object imaging procedure).
A few script lines as an example:

' ++++++++++++++++ Parameters ++++++++++++++++
Lat=45.85754 ' Obs. Latitude
Long=9.1166 ' Obs. Longitude (East=positive)
'
' Object selection criteria (GEM pointing East)
azi_max=150 ' Object Max azimuth
azi_min=10 ' Object Min azimuth
alt_max=80 ' Object Max elevation
alt_min=50 ' Object Min elevation
'
' .....................
'
' ++++++++++++++++++++++++++++++++++++++++++++
Sub Select_obj
' Object limits compare
azi,alt = EquatToAltaz(ra,de,Long,Lat)
if (azi>azi_max OR azi<azi_min OR alt>alt_max OR alt<alt_min) then
obj_ok=0 'Object discarded
endif
endsub
' ++++++++++++++++++++++++++++++++++++++++++++

The method as an interesting side effect. If I am lazy and I don't want to spend time for building-up the object list in advance, the script loads a big object list including thousands entries. I set the observations time limit to the full night and the script limit selection criteria will do the job for me. Next morning I find in the HD all the sub-exposures taken for so many objects all of them inside the current best visibility rectangle. (BTW I have already added the Telescope.List.Sort command to my script and i will test it in the field asap)

Emilio

[Forum_2015]

Hi Fabio,

Great update, thanks!

Can I just do a quick check that switching on jnow in the goto plate solve has no affect on findcoordinates (and distancefrom) which both still presumably require J2000?

Cheers,
Andrew.

[Forum_2015]

Great, thanks for the confirmation.