alacant

Hi everyone The shortest night of the year. Not the best time to lose 20 frames because you'd lost the guide star whilst asleep. Not sure why EKOS didn't recover. Usually it's rock solid. No doubt the INDI devs will tell me what I'd forgotten to do on this occasion soon enough! Stars everywhere; I'm not a fan of the latest remove-most-if-not-all-of-the-stars thing. We used to spend hours recording them. Now it seems we spend hours trying not to record them. Must be getting old! Still at a loss with the colour. Impatience more than anything... Anyway, thanks for looking and do post your -stars or no stars- comparisons. Always something to learn from them. eos700d @ ISO800

Hi everyone Any ideas what this is? nova.astrometry.net doesn't annotate it so I decided 's'. Anyway, it's quite a nice patch. Starting with at astro-dark, it doesn't reach the meridian before sunrise. This looks like a good plan in general; catch it early in the east and let it go all -what's left of the- night at this time of year. Process: not easy to fix the background mess. The colour is all over the shop. Any ideas for stuff like this where it's all gas and dust? Cheers and thanks for looking. os700d @ ISO800

Hi We have the 152/760 f5 which is the same design; 4 elements in 2 groups. A well corrected f10 objective lens and 2 Petzval correctors toward the eyepiece. Wonderfully flat wide field views. If you can extend to the EXOS II mount, so much the better as they're heavy beasts. I think the 127 is near on 8 kg. Cheers and HTH.

Hi If that's what you want to do, then perhaps keep it here? To begin, maybe pick one of your... ... Items and get that going? That way we can prioritize and help get you started along the right lines. Meanwhile, if you can get acquainted with a local astro club, that's by far the quickest way to make a start. Cheers

Ah, OK. I've never noticed it. I was wondering what I'd see if the mirror was warmer.

Hi I've never come across this before. How does a non-cooled mirror -without a fan- manifest itself? Cheers

Hi Is there any way you could leave the mount set up permanently? An upside down water tank, bin or roll off cover for the mount? Put a mark of the dovetail carrying the optics at balance and attach when it's clear? For me at least, it's the difference between imaging and can't-be-bothered! Cheers.

Yeah. I prefer vnc-ing into something which runs everything easily rather than on-the-limit--client server. I think that's me being lazy though. I've witnessed many an ap rpi failure, but few if any problems with something like an i7 with a ssd running Ubuntu. I think that with a 4Gb rpi it maybe possible to run the whole show. Cheers

Do you run everything from the rpi?

I like the large hammer; bench, stage right. Hoping that this will serve as our monthly/quarterly bump. Cheers everyone.

Ah, ok. There's the third thumbscrew at 120° trick but even so, I've never had consistency with it on either an ed80 or a 130pds. Not sure what telescope you have but the items you mention are likely to cost more than the telescope itself whereas the old sw 63mm single speed rack and pinion focusers are much better at holding heavy loads than the ds will ever be. They also bolt straight onto the existing baseplate. Have a look here. Cheers.

What focuser is it?

Now rotate it back and take another frame. Push the camera tight up against the focuser each time.

Hi Easiest -and maybe best- a black shower cap. HTH

Hi How does the flat frame look if you rotate the camera 90º? How do the flat calibrated images look? i'm guessing good since you mention that collimation via the Cheshire looks good. If the latter has cross hairs, then even more confirmation. OTOH, if the stars look distorted, time to investigate. Firstly, be sure to read the collimation myths. then, to help us diagnose, post a shot through a simple central hole collimation cap and also through the Cheshire. (links to) A light frame and a flat frame, the camera you used and its orientation would help nail it if necessary. Cheers and HTH

Yes.

This is with the APASS catalogue and a tweak using dt's velvia.

Thanks guys for your time and comments. Yeah, colour. By far the most difficult bit of the process. For me at least. Rather than use my eyes, I left it to Siril's photometric module. This was against NOMAD data. It could be that different databases give different colour. More variables! Cheers

Hi everyone This was supposed to be a warm up before heading south but conditions were worsening as the slight breeze gave way to pin-drop stillness. Managed 2 hours before the haze got soup-like and so making yet another session with Sagittarius in the no-go zone. I can't get the core stars resolved properly. This was a -poor- attempt using DarkTable's parametric mask, selecting the central bit of the core. Looks promising, but it's gonna need a few more rehearsals. Meanwhile, any other not-based-on-layer-mask-with-2-exposures-or-stretches most welcome. Clear skies and thanks for looking. 700d @ ISO800

Thanks everyone. The dealer will not send a replacement mirror but has sent a return shipping label for the whole telescope. Communication is very difficult with weeks and several messages before a reply is sent. I'm not sure if I should post a negative supplier review. Most of our stuff is second hand or just left here by visitors; I'm not used to taking new items out of the box but for the sanity of you all, I'm glad that this is not the norm. Cheers

Hi everyone Here is the main mirror from a new 203mm reflector. What do we think? Is this acceptable I wonder?

Thanks everyone Yeah, differences in use. I think the locking bolts bearing up -and no more- against the mirror cell is probably the best compromise. Cheers

Before you buy a guide telescope, try with your 130. Attach the camera and see how many stars are visible with a 2 second exposure. I've a feeling you're gonna need something more sensitive. Cheers

Hi The 152s has a f10 doublet as well as the correction elements in the focus tube. To correct any residual colour we used a #8 yellow. Best to try with a camera to see if it's acceptable to you. Visually, it gave the best views down by Scorpio and Sagittarius I've ever seen. HTH

Hi everyone I refer to the screws that you're supposed to tighten to 'fix' the mirror after you have adjusted the main collimation -the ones with springs- screws. I've had nothing but trouble using them; anything other than a light touch and they'll de-collimate the main mirror. My solution has been to fit springs to them but retain the bolt -loosely fitted- to retain the spring. That and fit stronger springs to the collimation adjusters. Anyone using them? Your secret? Cheers