A simple script to DEFOCUS with a specific offset

[Rodney Howe]

I'm new to ACP and not familiar with writing scripts. Any advice on how to create a script to do the following:

Set the focus reference to the Luminescence filter, take a short focused exposure with the Blue filter, then a short focused exposure with the Visible filter, then DEFOCUS with a set offset, .e.g +1000, and take a duplicate longer exposure on the defocused V filter . Repeat this 3 times, etc. on the same star.

Any help would greatly appreciated.

Rodney

[Jim McMillan]

Hi Rodney,

The next 2 paragraphs are taken from ACP's help file:

#DEFOCUS Moves the focuser the given number of integer steps away from proper focus just before acquiring each subsequent image. The focus position is restored immediately after acquiring the image, but this directive does carry from target to target, so unless changed, the focus will be moved away from proper focus before each subsequent image. This does not affect pointing images. For example: #DEFOCUS -150

This should not be used when you have an internal or off-axis guider and the image exposure duration would result in guiding being used. Doing so will obviously defocus the guider, probably not what you want! If #defocus is specified, the "aggregate exposure" algorithm will not be used to determine whether guiding will be used, only the individual exposure interval will be considered.

In other words, you only need add this directive to a Plan versus writing a script. (BTW, help for writing scripts is also in the Help file. Or, do what I do...just steal code from existing scripts is need be.)

I hope that helps.

Jim

[Bob Denny]

Hello Rodney!!

I'm glad to see you made it in and have ACP going. I'll let Stephanie know you're OK. I'll still call you today as she promised. But your question (which is really an ACP one, so I am going to move this to the Pre-Sales section since you're still evaluating) has an answer:

In your observing plan, include a directive #defocus nnnnn which will do the defocusing. I'm not sure I understand what your objective is, but to take the series of images you outlined. There is no concept of "setting the focus reference", you select a filter and take images. ACP handles the details. Let's say "short" is 30 sec and "longer" is 120 sec:

#sets 3         ; Repeat this plan three times
#count 1,1
#interval 30,30
#filter B,V
#defocus 0      ; Harmless if already 0
FM Cas   00:14:28        +56 15 11
#count 1
#interval 120
#filter V
#defocus -1000
FM Cas   00:14:28        +56 15 11

The info on making plans is in ACP Hep. Acquiring Images Automatically, Making Observing Plans. You can throw a #waitfor nn to wait for nn seconds, allowing you to pace the three cycles of images.

Edit: I see Jim Mcmillan answered while I was working on your answer. Thanks Jim!

[Rodney Howe]

I'll try this. I still have to learn enough ACP to get everything hooked up.

R.

Hello Rodney!!

I'm glad to see you made it in and have ACP going. I'll let Stephanie know you're OK. I'll still call you today as she promised. But your question (which is really an ACP one, so I am going to move this to the Pre-Sales section since you're still evaluating) has an answer:

In your observing plan, include a directive #defocus nnnnn which will do the defocusing. I'm not sure I understand what your objective is, but to take the series of images you outlined. There is no concept of "setting the focus reference", you select a filter and take images. ACP handles the details. Let's say "short" is 30 sec and "longer" is 120 sec:

#sets 3         ; Repeat this plan three times
#count 1,1
#interval 30,30
#filter B,V
#defocus 0      ; Harmless if already 0
FM Cas   00:14:28        +56 15 11
#count 1
#interval 120
#filter V
#defocus -1000
FM Cas   00:14:28        +56 15 11

The info on making plans is in ACP Hep. Acquiring Images Automatically, Making Observing Plans. You can throw a #waitfor nn to wait for nn seconds, allowing you to pace the three cycles of images.

Edit: I see Jim Mcmillan answered while I was working on your answer. Thanks Jim!