alacant

Hi No, you can keep the existing rings. They just need a much wider spacing. A (at least) 50cm long Losmandy width dovetail with a rigid box section to tie the top of the rings keeps the tube rigid. You can make the plate from 500 x 15 x 100 mm aluminium plate. We use 60 x 20 rectangular box for the top rail. You local window-frame supplier will get them for you; a round of drinks works wonders;) Don't forget to also replace and add extra proper mirror springs and seal the primary to its cell. We only suggest the eq6-r because the one's we've witnessed just work with the minimum of fuss. iOptron mounts don't. I hasten to add, that is just our hands on experience in Spain. I'm certain that there are good iOptron mounts which just work too. HTH

Hi Another gso203 f5 user here. We had to invest a little time to being it up to imaging standard but the effort is minimal. I'm sure a similar investment on your pds would yield similar results. E.g. no Newtonian we've ever seen uses adequate mirror springs nor supports the tube with an adequate dovetail. I think we're more limited by seeing than the quality of the optics anyway. Here, it's only once or twice a month that the seeing will hold guiding at 1000mm, but when it does, you notice it. I'd lean toward bringing your pds up to speed, wait for the steady nights and spend the budget instead on an eq6-r. Cheers

Hi everyone Good seeing with steady stars aided by EKOS' excellent SEP multi-star and rms values between 0.4 and 0.6 all night, goes some way to showing that having expensive telescopes isn't the be all and end all; we're more dependent upon the state of the atmosphere than on the quality of the optics. That's something I never used to believe, but these days I'm almost convinced; I don't think this would have been as good with a more turbulent atmosphere. Certainly not with my processing patience! Thanks for looking. Any thoughts on seeing and stuff most gratefully received. 700d + gso203 f4.9. siril startools. 28 x 5min ISO800

Our moon guy uses this, but sorry, I've no hands on with it. I'm certain there'll be more economical -and lighter- items suggested herein. HTH

'... flex' So I believe you have the collapsible tube. So... Using a T2 adapter and nosepiece, see if your camera reaches focus. If it does, do nothing. If not, to enable focus to be reached, extend the telescope as normal. Now loosen the clamps holding the extension rods and push it back from whence it came a centimetre at a time until until camera comes to focus. Mark and clamp at that position when you want to do photography. Cheers and HTH

Hi We find it easier -and more economical- to simply clamp the tube a cm or so shorter. Any eos T2 ring will do. Cheers

Hi Yes. Well done. You could also see the 'non-centred-ness' on your curvature plots. Did you try with the focuser at differing extensions? If so, and the laser remained central, you're good to focus (sorry!) attention on the ff spacing. Cheers

Good luck and do please post your image. We're particularly interested in dslr stuff with beginner/affordable/unusual imaging equipment. It's not the gso you may think, rather their most basic offering. Useless out of the box, but a small investment -mainly in time- soon brings it up to imaging standard. Cheers

Hi everyone TBH, for nearly 5 hours, I'd expected better. An earlier attempt from the same session of around half the number of frames wasn't much different. Still thinking... Cheers and thanks for looking. eos700d on gso203

Hi Try the phd2 internal así driver as well as indi-asi. But anyway, best to post the indi and phd2 logs. Then we'll have a much better chance. Otherwise, we can only guess. Any reason you're using phd2? EKOS has en excellent guider so no need for third party apps. Keep it simple? Cheers

3 off. Move the tube rings too of course so as to give some wiggle factor. Adjust until a laser collimator in the focuser is exactly central in the objective lens; use a circular, centre-marked paper mask to see where the beam hits the lens.

Loosen the grub screws on the focuser retainer (the silver coloured ring) and reseat it, tightening in small increments. That usually does it. Cheers

Hi No need to have clear skies. Check every bit of your method using the EKOS simulators. On your actual profile, don't forget the check the dither box. Yes, very much so. the 18Mp eos sensor responds well to the dither. Nice clean images, easy to process. Cheers and HTH

Lovely shot. Don't forget to lose any type of dark frame, dither around 15 pixels between each exposure and stack with a clipping algorithm. That should kill the banding and reduce a lot of noise. Cheers and HTH.

Lose the Baader (tilt-prone) adapter and go with the m48 connection instead. This needs to be at least 58mm from the sensor. To check collimation and tilt you really need to execute the modifications we mentioned. Cheers

If it's the Baader cc, astigmatism. The cc needs to be closer to the sensor. Tilt, yes. The GSO does not hold collimation out of the box. There's other stuff, if you can confirm the id of the cc. Cheers

Hi Maybe even better, do a few nights real time sitting next to the telescope with a laptop. A €100 refurbished Dell from eBay is fine. You can then always vnc into that if (when?!) it gets too cold.

Hi We supply remote and some our own stuff on the ground. We use mini-pcs at the telescope running Ubuntu 20.04, Kstars and EKOS. It's as bulletproof as we know, especially over the network. Maybe give yourself a bit more umph with a decent pc rather than the pi?

The shadow of the mirror. HTH

Not really enough information, but a few pointers... We think it's local light pollution casting a shadow. Do you use a light shade/dew shield? Our guess is that whilst flat frames will cure the dust and vignetting, they will not cure the secondary shadow. But you won't be processing anywhere near as aggressively anyway, so not to worry.

Small amounts are fine. Post a shot - looking centrally down the focuser - through your Cheshire crosshairs

Telia. Try: https://docs.google.com/document/d/189O1EzG4VDspu-okPl5rIYlmp1JSgepeKN58NmrF-GI/edit?usp=drivesdk

Remember that other than reflection, the secondary has no optical properties. It's just a flat mirror. Correct offset is inherent when the secondary is correctly centered on modern Newtonians. You don't need to set it. Be sure to read the collimation myths. Both telia and seronik tell it exactly as it is. Cheers

Not nearly as much as the mirror clips.

Flat glass glass is cheap to replace: https://a.aliexpress.com/_uyFNrV We too have damaged primary mirrors but don't notice any image deterioration. If you do, @vlaiv's idea of the pirate patch to the rescue. Good luck anyway.