Sequence questions

I tried to do my first sequence in voyager last night and it failed to platesolve and to autofocus at the beginning of the sequence. ASTAP is definitely installed correctly and the path to it is set in the voyager settings. As for autofocus, I successfully added 2 vcurves to the profile and did test AF runs on all 7 filters so I am not sure why its failing.

At first I had the seq platesolving setting set to use Luminance assuming that if I started with luminance and manually did an AF run to get into focus Voyager would center the target, switch to the narrowband filter specified in the actual sequence, and begin imaging. That didnnt seem to work. Starting with an in focus scope (lum) the platesolving to center target and kept getting “Plate Solving Error: Solve Failed Error reading image file”. Voyager kept retrying and eventually got to where it was supposed to be (I think).

Then it switched to the first narrowband filter in the sequence (Sii) and attempted to run autofocus but gave the error “Find Focus Star: Star NOT Found”. I know there is a suitable focus star in the field because the field is wide and I manually did an AF run with the same filter earlier. It appears Voyager then retried autofocus but with the Lum filter instead, failed a few times and gave up. I would greatly appreciate anyone who could help me work this out.

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Try to get everything working reliably ad hoc before using in a sequence. In my experience ASTAP is a very reliable plate solver and fast with it.

No issue binning 2x2 for focus runs and for narrowband it’s advisable. You may also want to force Voyager to pick brighter focus stars.

The unable to read file is a strange one as it seemed ok later on. Leo may have to chime in on that one.

Not sure on your mount but you may want to add some settle time after a slew.

2 v-curves is a little on the low side, try 8 or 10

I thought I did have everything working reliably. I can take a sub and platesolve it manually in the onthefly tab. Also there should be settle time after slew inset it to 20s in the setup mount tab. That has worked well for me in other software. As for the autofocus it seems like voyager doesn’t like to run AF too far outside of the CFZ. That is understandable however without offsets it’s unavoidable since there is a large offset between the rgb and narrowband filters. Changing between Lrgb and running AF works fine but going from an LRGB to a NB filter also fails because the star is too far from focus.

This is not true, Voyager do not know CFZ and work for HFD. All the applications using vcurve in non linear zone of focus need to start near focus or routine will not work. But Voyager have also a real vcurve method for focus on a single star, this allow to be executed also in case of not closest focus at beginning. Also is important to choose the right magnitude interval for type of filter.

I wasn’t implying Voyager should know the CFZ, I’m just saying that if the scope is too far outside of the CFZ autofocus will fail. It gives the error that the starting HFD is too high. If I focused the lum filter and then wanted to focus HA for example I had to manually move the focuser so that the steering HFD on HA is lower and the autofocus runs. I won’t be sitting around to do this though as normally I leave the rigs unattended during imaging so I’m just trying to figure out a solution.

This is already not true … if the filters coming from the same brand or have the same tickness.
Use different brands of filters at same type with different tickness is something really to avoid during the setup choice also because the backfocus change.

Voyager do not use Offset , just in Voyager Array version.

If you have same brand this is something doesn’t happens … if you filters coming from different brand you must separate the sequence narrow to broad in Voyager. If the problem is just the plate solve you can ovveride the filter to use in plate solve in Voyager and changing timing directly in sequence.

I do see that offsets are in the array version and I did purchase it I just am not at the point of using it yet because I am still at the stage of getting each individual rig working in voyager. Using different brands of filters has never been an issue in the past because all other software I used had offsets so I’m just looking for solutions to adapt to Voyager.

Voyager not use offset ! Array use offset if you need for technical reason due the complexity of operations but not for filters related questions.

Yes I understand Voyager doesn’t use offsets but Array does. I’m just not at the point of using Array yet so I’m trying to adapt to Voyager.

In a major of setup using different tickhness of filter is a big error … offset or not … for who have a backfocus you must respect it. I suggest you to check if you are in this situation.

Solution is separate narrow from broad and use for narrow override of plate solve with a filter f the same tichkness and right binning and exposure lenght

Otherwise … if you are running LocalField focus … switch to single star RoboStar autofocus that allow bigger difference in focus point.

Previous imaging software I used easily dealt with different thickness in filters. I have learned that Voyager does not so I’m just here looking for solutions so that I can adapt to Voyager. Once I have Voyager working properly on both rigs I’ll be moving too Array and since Array does use offsets the difference in thinness shouldn’t be an issue.

I will try this, thank you.

Also, I think I know the source of the platesolving issue. My mounts driver was not synced with pc time so the mount most likely wasn’t pointed in the right place when trying to solve. Have corrected issue and will try again.

Using ASTAP as a blind solver would solve that.

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Im using ASTAP as blind solver already. I’m 99% sure the issue is sync time because when mount time is wrong it will think things are in the wrong position in the sky. I’m just not used to having to manually sync time during startup. These are new mounts.


You could always determine what the close focus positions are then use dragscript to goto those positions before the autofocus. The trouble with this method is that filters with the same focuser position would have to be done together (same sequence); this may mean you have to use a few sequences and hence complicate your workflow. The purest and easyiest method would of course be having filters the same thickness.


My LRGB filters are of the same brand and my narrowband are of the same brand. Neither group are perfectly parfocal but they’re close enough that when switching between LRGB or NB focus will be close enough that robofocus can run successfully. So I’ll just do broadband and narrowband as separate sequences. When one seq is done I can use your drag script idea to move the focuser to a point where autofocus will successfully be able to run with the next group of filters.

Fortunately Array uses offsets so I will be able to operate as I did pre-Voyager but I’d like to get a good handle on the base version before resuming my tandem operations.

Thanks everyone for chiming in. I can see how powerful this software is, it’s just always a task adapting to new software.

I stand to be corrected but I believe that only Slaves in the array use focus offsets.

In general with Voyager the question is not Can I do it but which way should I do it.