AKB

I've done as much checking on the cables as I can. Even took the lid off the controller to check the connectors there. There's nothing wrong I can find with the cables, so I am left with the conclusion that it must be the RA channel of the controller. I will be send it to Lucas to check.

Good to know. Your procedure is very much what I had been doing for the last 18 months, until this happened. What, then, should be required to “correctly initialise the mount”, seeing as its blinky now?

Velcro!

Have done all the diagnostics I can, and I think that I’ve narrowed it down to the controller itself. I’ve exchanged emails with Lucas Mesu and I’m planning on sending him the SiTech box to check things out. Complicated by the fact that Royal Mail isn’t sending parcels abroad at the moment. Other couriers seem outrageously expensive…? Lucas tells me that he’s never seen one go wrong before… In the meantime, I’ve ripped all the kit out of the observatory and replaced the mount with my Avalon M-Uno and just my C9.25 Hyperstar for EEVA use. Tonight’s the first one I could see any stars, but I had to go out to visit friends, so haven’t yet done a PA on the setup. I doubt that I’ll get the Mesu running for the rest of this season, but perhaps I’m just being pessimistic. Thanks for asking! Tony

Apparently no change with loading a backup file. Looking very much like controller/cables. 😢

Much appreciated, Peter. I will give #1 a go tomorrow. I have tried #2 already, swapping both the drive and the encoders with the connectors you mentiond. The other axis slews when I do that. I've also sent a message to Lucas Mesu to see how familiar he might be with this problem. Will let you know how the config files goes... Thanks again, Tony.

Thanks again. I’ve applied to join, but not yet been approved!

Thanks. I’ll try there too.

@whipdry @Jonk Thanks both for the suggestions. I’ve just given it a go and it shows the same symptoms without a handset attached. I’ve also posted on the groups.io forum, so we’ll see if that brings any joy. Appreciate the help anyway. Tony PS: this is after having put the controller itself in the airing cupboard for a while to see if moisture there was the issue!

I swapped the motor drive plugs going into the Sitech box, and now the other axis shows this behaviour. Almost definitely a controller issue, then ... ? I see from here https://www.siderealtechnology.com/store.html that a new Servo Controller 1 is $400. 😟 So I'd have to be sure that's the issue. Ideas welcomed!

Help! Turned on the mount (Mk 2) last night and the RA started slewing immediately until it suddenly stopped (some encoder limit??) It does this every time if I manually turn the RA back to its usual park position. The controller LED 1 blinks and the app shows "blinky" mode. The servo obviously works, and perhaps the encoder, since it does come to a stop. Perhaps a Sitech hardware issue? Any advice / suggestions for further diagnostics welcomed. Are new Sitechs easy to acquire? The thought of having to ship something to Europe is dire in this post-Brexit world. Thanks in advance. Tony

Is this you @gorann ? https://apod.nasa.gov/apod/ap221221.html Congratulations! Tony

Thanks Olly. Yes, lights on cameras, who would have thought? I think that some these days allow you to turn them off with a 'stealth' mode. Less of an issue, in general, when you put them at the other end of the scope.

Any "best practice" advice available on this? I've gone as far as a semi-circular route with the power and USB cables going down opposite arcs to keep the diameter of the obstruction as low as possible. Anything further to consider? Great image, of course! Tony

Not sure of the size, but for the ultimate in flexibility in attaching to a Hyperstar, this modular system has everything including variable length spacers… https://www.firstlightoptics.com/baader-filters/baader-ufc-universal-filter-changer-system.html …alas, also the ultimate in costs, I suspect.

I would say A. Effectively from the top of the basic Hyperstar assembly.

This shows that I can get collimation closer, but also very clearly demonstrates the curved cable form that I posted earlier in the thread. When in focus, this means that the diffraction spikes from the cables are very effectively suppressed... definitely worthwhile doing. The diagonal chip measurement here is 23mm (it's an ASI294-MM.)

FYI, this is a quick snap I just made for collimation. Not well collimated, butthe correct spacing and you can see that the images are much more uniform...

Well, this looks like progress! For the defocussed image, I’m a little concerned about the strongly ellipsoidal nature of the off-centre stars. I’ve not noticed that so strongly on mine before. Wondering if that might be a spacing inaccuracy? Or perhaps it’s normal for a C8? Beats me how you found any stars at all this evening! All cloudy here.

This only works, IMHO, if the screw you chose was aligned with lowest point of the optical ‘tilt’? From a practical point of view, a little leeway for all three of them helps. From what I’ve read here, your practical expertise exceeds many who might be happy to call themselves ‘engineers’ (which, BTW, seem barely to be technicians these days. Although, I give you, that the term engineer has a much higher standing in Europe than in the UK.)

Not quite the technique I’ve used. For me, with the scope pointing to zenith, the short locking screws can be relaxed and then the Hyperstar lens just sits on the three long adjustment screws. Then it’s just the same as for adjusting a Newtonian. A rich star field will mean that it doesn’t matter that adjusting the collimation moves the image, since there are always stars near enough to the centre. You also get a feel for how things vary off centre. For me, again, with a relatively small chip, it’s pretty good across the field.

I use one of these for cable routing https://www.firstlightoptics.com/adapters/buckeyestargazer-cable-router-for-front-mounted-cameras.html clips nicely onto the rim of the scope

Several things to note: Collimation is most easily accomplished by pointing the scope to the zenith. This way, gravity helps to keep the hyperstar actually resting correctly on the (long) collimation screws. The short screws should be loosened and the collimation achieved with the long ones... then tighten up the short ones. For focus I have used a Bahtinov mask in the past, but now rely on an autofocus routine which usually nails it. If we have a good night tomorow or soon after, I will try to capture an image with a mask for you, if that's any help, so that you can see what it should look like. When collimating I simply use a rich star field with defocused image which gives a lot of points to check the alignment on all over the field of view. I'll get an image of that too. If you want a comprehensive discussion of tuning the hyperstar, then have you seen this: https://www.cloudynights.com/articles/cat/articles/the-amazing-hyperstar-a-guide-to-optimize-perf-r3013 It's an interesting read, but I wouldn't suggest that you even consider much of this until you have the basics sorted out. Tony

Hi there. I have a C9.25 with a Hyperstar that I use all the time (for EEVA.) In fact, this evening I was out there collimating it for the start of a new season (not having touched it since April!) What seems to be the problem?

Worked for me too! Thanks.