Capability for Multiple Runs on Same Targets

I have a series of asteroids I want to image. The same asteroids need to be imaged at intervals throughout the night. I have been importing them up to 3 times in the same sequence. Then I have to go in and make each target name unique. I know that is the design of SGP, but I am wondering if SGP can allow the same target names in a given sequence or some way to activate a follow on sequence which can activate a follow-on sequence and so on.

This would be useful for asteroid and comet astrometry as well as CCD photometry of some fast period variable stars.

Best regards,

As the Target sequence ‘SGF’ files are just text based, you could probably write your own target file with the appropriate settings as needed.

It would need a little work deciphering it all, but when done, it could then be made scriptable…

Good idea. Thanks!


I simply clone add a number at the end of each target name. For example, I was running M67 for photometry. M67-1, M67-2, etc.

Hi ewiley,

  Thanks for the suggestion. That's basically what I did. Just was

mainly wondering why there is the limitation of having the target
names all be different. I don’t see any reason for it. Do you know
why Ken and Jerod made that restriction?

  I use the target name to create a folder with my acquisition

files, originally hoping that during the night, and
night-after-night, the fits files would go into the same folder
for the same object. Now, as well as renaming the targets, I have
to merge the folders. Meanwhile, I followed Dr JuJu’s suggestion
and investigated the SGF files. Turns out a couple of simple
macros in Notepad++ seem to get around the problem but I’m not
sure that it won’t cause other run-time problems. As soon as the
weather gets better I’ll do an actual run and see.



Seemed like a good idea at the time? I honestly can’t recall. But you don’t have to output the target name in your file path. You can just remove the %tn specifier and manually put in your own folder.


Hi Jared,

  I am trying to set up SGP for automated asteroid photometry. This

will involve many short exposures of batches of asteroids each
night. The exposures of a given asteroid will be separated by 30
minutes or so with three sets of observations on that asteroid
during the night.

  I use the planetarium program, C2A, to automatically generate a

list of asteroids and positions using its Observation
Planner/Scheduler. C2A has an output text format similar to Starry
Night so I use your import feature to load three sets of the same
asteroids into SGP. I would like to use the %tn to direct the
images of a given asteroid to a folder that has the asteroid name
for all the sets. I know I can output to another folder but I
might have 100 or more images of all different asteroids there
which is somewhat cumbersome to manage.

  I have developed a couple of macros in Notepad++ to modify the

.sgf and get around the error message that happens otherwise. I
haven’t tried it for real yet due to bad weather; perhaps tonight.
Are there any gotchas in doing this that you can see?

Regards and thank you for the great program,


Well, guess what? I just ignored all the error messages and clicked the x at the top of the Target Settings box and SGP accepts all of the inputs. It seems I can do things the normal way (almost) so this is a non-problem for me. SGP does what I want! I will consider the error messages from SGP more as informative messages.