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My name is Ant, and...


Ant
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I haven't had an image since April 16th.

Till last night. :)

It didn't go well... My usual imaging laptop decided to stop working with ASCOM, so whilst during setup it was fine and i waited for it to get dark, as soon it got dark and I went out to align on a star and everything just wouldn't work. So that laptop got thrown (literally) into the back on the car.

My main laptop however worked ok.

I have issues with funny stars with my scope in certain configurations, I cannot work out whats causing it. It's not the camera/fw/oag/filters as I didn't get it on another scope. But if I remove the FW carousel I don't get it... very strange. I've had the scope apart and everything seems to be OK. I was hoping that maybe just taking it apart and putting it back together would help but it hasn't.

I think the next step is a laser collimator to check the collimation of the focuser. But that involves money, and thats a bit short on the ground at the moment.

This image is of the elephant trunk, 4 x 20 minutes, no flats, no darks, no bias. Stacked in DSS, processed in CS5.

I really didn't enjoy being at the scope again, which is a shame...

Ant

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Commeriserations Ant - most frustrating when you wait so long to get out there and then things go wrong :( I've got guiding problems ATM with PHD and ASCOM - PHD can no longer move the mount, though CdC and EQASCOM work fine - very odd! Apart from the funny shaped stars, that's quite a good image :) I think your scope problem is showing in rather soft focus as well though.

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Commeriserations Ant - most frustrating when you wait so long to get out there and then things go wrong :( I've got guiding problems ATM with PHD and ASCOM - PHD can no longer move the mount, though CdC and EQASCOM work fine - very odd! Apart from the funny shaped stars, that's quite a good image :) I think your scope problem is showing in rather soft focus as well though.

The softer focus may have actually hidden the issue slightly... But when I set the focus (fwhm or whatever it is) was down into the 1.5 region, I've had better but seeing may have rubbish last night.

Personally I think that the focuser is shot - I'm not a fan of crazy fords - the vixen I had had a good R&P and it was great!

Cheers knobby, hopefully soon.

Ant

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Welcome back to the planet of the living Ant :)

Have you checked for the same problem on an identical scope? Maybe it is just that combo you have that doesn't want to play nicely together?

It wouldn't be the weight reduction of the assembly by removing the carousel that helps the focuser cope better would it?

What laser do you need? Want to borrow my hotech?

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Hi Ant - I do empathise with you as I was in a similar position... I got my mount out for the first time in maybe 10 weeks on Wednesday night - Took me ages to set up and then my goto couldn't find my first three chosen Ha targets (or maybe it did, but I couldn't see anything resembling a nebula on screen). I eventually got M27 totally filling the frame and the guide graph was as flat as a pancake, so off I went - The first sub came in and 1 minute later the mount rebooted. I managed to restrain myself from throwing the whole lot in the hedge and packed away instead. Not an enjoyable night at all...

Although Tim's offered anyway, you're quite welcome to borrow my 2" Hotech and Farpoint collimator too - I'm amazed at your FWHM value(s) though. Where I live I don't think I've ever got below 2.5. I know it's dependent upon quite a few things but even so...!

I think you're right - Although maybe focus / transparency may be part of the issue, the image seems to show teardrop shaped stars falling from top right to bottom left. Silly question, but is this shown on ALL subs or just the resulting stack?

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Aren't teardrop shaped stars normally associated with backlash?

Glad that you got out Ant, but it's a real pain in the butt when things just don't go well, it is really demoralising. I hope that you can soon get it sorted and feel happy with how things progress.

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I've had the issue ages, thanks for all the pointers (and offer of loan).

FLO is sending me a hotech laser thingy, so I'm sorted on that... :)

It's not a weight issue as I have once empty slot in the FW, if I image through that I do not get it... Also I know that it isn't backlash... On bright enough stars I get the issue with 10s, 1m or 10minute subs (left, middle and right below respectively).

dodgy-star-set.jpg

I am considering using the ed80 without filters with the 300D - might try that tonight, and buying a cheap second hand ST80 or ST102 for narrow band imaging.

But any suggestions on the issue will be fully investigated.

Cheers

Ant

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It's not a weight issue as I have once empty slot in the FW, if I image through that I do not get it...

Sorry Ant, I am such a rank amateur, but if when you image through an empty filter wheel slot you don't get it, but the minute you use filters in the filterwheel the funny shape stars happen. I would start thinking that the carousel isn't sitting square in the filter wheel perhaps. I don't know how you'd check that or even go about soting that issue as you can't really wedge anything as that defeats the filter wheel being used as naature intended.

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Hi Sara,

I've had another scope and just move the H9/FW/OAG/SCA in one piece the other scope and the funny stars went away...

So the latest thinking is that the focuser isn't sitting square in the tube and that the funny stars are caused by a reflection from the filter - it's really the next thing to check.

Ant

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And you are only getting this at certain scope orientations or does it happen no matter where you are pointing the scope?

Can you remove the filter wheel but manually screw a filter into the imaging train? That would determine whether it was due to the filter wheel not sitting straight or a reflection problem due to the focuser...

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Next time I'm out I'll take an image at the zenith - or as close as I can get to it before the FW/Lodestar hits the legs...

I'll also image in the East for a little bit and then swing round to the West and see if the orientation of the BLIP changes.

That's something that I hadn't thought of :).

Ant

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