Simplest way to do bias, darks, please

Situation. New user. Have setup a couple of systems, and run a few sequences, on the fly, successfully. Have never looked at DragScript.

I can’t see how to do bias and darks. Autoflat worked easily, was intuitive. But, otherwise Voyager seems to insist on communicating with the mount, having a specified target, and platesolving to the target.

I don’t need any bells and whistles, just need to do the simple thing. Cool the camera to a specified temperature, shoot a specified number of frames at a specified exposure, gain, and offset, download and store the images in a file. I’d prefer to use sequence (which I pretty much understand), but if using DragScript is the _simplest_way to do this, so be it. I would like to see exactly what the DragScript would look like.

I’ve searched, but didn’t find what I needed. Perhaps my search was defective, if so, I apologize.

Last point. This needs to work when I just cover the lens (some scopes) and when I pull the camera and cover it (my RASA).

Thanks for your help.


sorry but the sequence was born to do light session not bias and dark only, for this reason it try to add info to FIT header coming from telescope and throw an exception.

For Bias and Dark you must use the DragScript Precompiled Script dedicated to this task, just personalize it. I remember to you that DragScript is not a language or script… its just a drag and drop system to compose the Voyager actions. You dont need to write code.

Attached and image that explain how to do:

Here the link to the wiki explain:

If you want to use the Sequence tool solution is to clone your profile, open the cloned one, change the mount with a simulator and then use the sequence you have created.

All the best

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I tried the sequence approach. Cloned my lights profile, left camera as before, set mount to “virtual array” (I presume that’s what you meant by simulator), changed everything else to none.

Connected the camera and the virtual array mount. Created a sequence, identifying the exposures as bias. OK’d the sequence and executed it.

Gave me an error that it wanted target coordinates. Gave it a random target (M15) and tried again. Gave me an error that “This is a virtual mount… operations forbidden.”

So, I’m stuck.

Now questions on the DragScript approach. What does the 25 in bias25 mean? I have no desire for a time limit, just a number of exposures. I presume I can omit the line with the time limit, and set the block to repeat n times? If I want to do just bias, I presume I can omit the 300 and 900 lines?

Once again, I’d connect just the camera and the virtual array. I presume I set temperature, gain, and offset somehow in “Commands”? Then somehow execute the DragScript?

I’d still prefer to get the sequence approach working. That I understand.

Virtual Array is dedicated to Multi telescope array for professional isnt a simulator.
You must choose a simulator from one of ascom.

Bias25 is the name , 25 is the temperature of camera to remember at which temperature are done the bias, you can choose what name you want, you can erase all the block of time or dark no needed.

Once again virtual mount is not a simulator.

All the best


See this:


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Hello Peter your suggestion is on to-do list … a long list but will come.
Thanks for reminder.

All the best


Thanks, Leo. That worked. I just needed to know exactly this: Use the ASCOM mount and set it to Simulator. Put a dummy target in.

Those would be obvious to a more experienced imager. But were something I’d never done before.

Peter: I saw the request, and agree. AutoFlat worked great. Unfortunately the request didn’t deal with my immediate concern, so I posted.

No hurry, Leo. The work around works fine.


I used this method and for gain/offset set it was showing to use the native driver which i did for my ASI183MM. When I connected the camera it had gain 53 and offset 10 however the FITS data of the taken DARKS and BIAS show instead GAIN 0 and OFFSET 0 value. Do you know why and how to fix it?


Hello Seba,

in Dragscript you must specify the offset and gain in the configuration of the block or DragScript engine will use 0 .

All the best

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Hi I’m just getting slightly familiarized with Voyager after playing with SGP and NINA for a while and the dark/bias vs lights vs flats thing seems a little awkward for me as well. For example the file naming doesn’t work quite the same so it’s hard to have all the lights/darks/flats end up in the same subdirectory organized by target.

There’s also a bug of some kind where I move to the zenith to take the flats with a Pegasus FlatMaster and it thinks it’s still pointing at the target and keeps warning me that I need to do a pier flip when the telescope is all the way on the west side of the pier and not even tracking.

I think it would make more sense to have a single kind of sequence where flats would just be another event type where the exposure could be determined automatically. That would work really well if there was ever an option for determining the light frame exposure times automatically too. It seems like the same rules for adjusting the flat exposures based on differences between filters would be useful for lights as well. One might want to target a particular background sky brightness or something like that so you would get shorter exposures in light polluted areas and longer ones with darker skies.

In general it would be really great if there was a higher-level way to configure a sequence, so that I could just pick which filters in my filter wheel I wanted to use and it would be smart enough to know that I needed light and flat events for each filter, and then based on the exposure times for the lights and flats (perhaps determined dynamically as mentioned above) it would shoot darks with matching exposure times.

Ideally it would also be easier to apply the same sequence to one or more targets based on a variable or list which might be supplied by an external script. Even more ideally it would be nice if everything in DragScript had javascript (or python or perl or whatever) bindings so that every parameter of every action could be computed using any logic I want and also so it wouldn’t take about 15 clicks/drags/keystrokes just to do the equivalent of “x=0” in the middle of the script somewhere :slight_smile:

In the meantime one really simple suggestion while I’m at it: If I change the number of times to repeat the events in a sequence the Repeat checkbox should get checked automatically by default. Or better yet just get rid of the Repeat checkbox since you can just set the number of times to 1. I’ve forgotten to check the box at least a couple of times only to have the sequence end after just a few minutes when I wanted it to run for hours.

Also one question for anyone using TheSkyX: Is is possible to suppress the dialog box that reminds you to cover the telescope when shooting a dark and then uncover it when shooting another light? This will make Voyager hang waiting for TheSkyX and you will never even see the dialog box if TheSkyX is minimized (and Voyager minimizes TheSkyX automatically on connect which at first made me think it caused it to crash :slight_smile: ).

The statefulness of TheSkyX in general seems like a really hard thing to control in such a way that you can guarantee that Voyager can control everything correctly. For example I’ve gotten into a state a few times where Voyager can’t seem to find the photos that it takes for plate solving using TheSkyX’s camera control. I think it might be related to the “automatically save photos” settings in the focus tools tab as opposed to the take photo tab. It causes all plate solves to fail in Voyager which in turn causes precise pointing to fail which in turn causes sequences and focusing runs with AcquireStar to fail.



Dear Steve, i’m starting to answer to all you observation but i understand you have some problem on setting up all included in TheSkyX setting that are not a Voyager question but your way to do the thing that for us is not in the right way.

So Voyager isn’t SGP or NINA, i think if you found what you ask in this application why you want Voyager to become like them.

Voyager is different in better or worst mode.

Clear skies
Leonardo Orazi

Hi Steve,

I control darks/flats/lights from Voyager directly, TheSkyX acts as a dumb camera control interface. If you want to take calibration frames using SkyX then there is no way I know of suppressing the dialogue; SkyX is in control at that point.

As for plate solving, I use The SkyX automated image link (even if not using that programs imaging interface. It is super fast, especially the allsky blind plate solve.

I’m out shortly but can forward more detail in the morning if needed.


Like most Voyager users (I suspect) I’m trying to move from a more manual workflow to a more automated one. Right now I’m just trying to automate a telescope right outside my house but starting later this year I’ll be using a remote observatory almost all the time.

I like a lot about Voyager but no application will be the best in every single respect so if App A has 20 features you prefer and App B has 3 features you prefer it’s natural to hope that App A adopts those 3 features from App B.

Apps almost always improve over time since there isn’t time to develop every feature for v1.0 and sometimes when you add new features they start off as fairly separate things and then later on they can be refactored and integrated more seamlessly.

I certainly prefer the approach where all the control is done from a single app (whether it be Voyager or SGP or NINA) and everything else is just an ASCOM driver or whatever that you don’t interact with directly. I switched to Voyager and TheSkyX at the same time when I got a Paramount so I’m trying to get used to having two different applications that each have their own state and can fight over various settings which can be very confusing. It seems like I need to interact directly with TheSkyX in the process of getting things setup such as when doing a T-Point calibration, rough focus, getting all the settings right for plate solving to work correctly depending on which telescope/flattener/reducer/extender/camera I’m using, etc. Then I switch over to Voyager to automate everything from there.

I’d rather I didn’t need to use TheSkyX at all but I don’t seem to have a choice with the Paramount. I was just pointing out that depending on what I was doing in TheSkyX in order to get the basic functionality working, it seems like it’s possible for it to be in a state where Voyager won’t work with it. Voyager is very good about setting all the options the way it needs them in TheSkyX but there may be one or two that are missing which can cause problems like whatever was causing Voyager not to find the pictures it was asking TheSkyX to take. TheSkyX was definitely taking the pictures and saving them but I think they weren’t being saved with the names that Voyager was expecting.

Then there was the other issue I mentioned where TheSkyX likes to keep track of whether you have the lens cap on or not and remind you when to put it on or take it off. Unfortunately it doesn’t really know whether it’s on or off, but when the last frame you took is a Dark and then Voyager asks for a Light, it will assume you have the lens cap on and pop up a modal dialog box asking you to uncover the telescope. It won’t take the picture until you dismiss the dialog box. If TheSkyX is minimized then you don’t see the dialog box and everything is stuck. I was asking if anyone knows if there’s a way to turn off that dialog box or maybe there’s a way for Voyager to control TheSkyX so that it won’t display that dialog box when Voyager requests it to take the photo.



Dear Steve, Voyager doesn’t have problem to manage TheSkyX and a lot of users (also me) use it from years in Voyager, sometime i must go over the TSX developer and do patch to some changing but is natural. So probably you want to do something that isnt possible to do or not necessary or simple cannot be done. I think isnt so many correct coming in the forum and talk about issue that doesn’t exist or are a bad mode to use integration or are a misconfiguration. Some setting aren’t reachable from Voyager and you must operate directly in TheSkyX.

You are on trial I think … like all the things that we dont like just dont continue with the trial if you dont find in Voyager a right solution.

So please if you have problem with Voyager using support mail to solve your problem with Voyager.