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The link above sh0uld work lee

Done it a couple of times already but I will try again.

very nice, see you put ptfe on your colimation bolts 👍

I've been using astro sharp last week or so and it seems good. I'm a noob but might be worth a try?

Thanks for the info! So I understand the gain; and u understand the clipping part but forgive me for sounding dumb I’m totally clueless in regard to “aim for 3000 ADU average”. What exactly is that and how would I determine that I’m averaging that 3000 number?

Watch the video and disassemble it in stages like he did and check the various sets of securing screws. Good luck.

Awesome thank you so much that’s great info I’m going to do some searches this evening!

Planetary Nebulae are worth the effort of finding as they look very impressive with a big Newtonian. Here's one of my favourites, the Eskimo Nebula (NGC2392), observed in early March with an 8" Newtonian with x1.7 Barlow, x400 gain (50%), 77 x 15s frames.

Thanks Ian. I will try again tonight with the clutches. I found a replacement motor with encoder etc, new, but I don't want to fork £100 if I am missing something with the clutch etc.

What he said^^ lly

Out of curiosity, which 135mm lens did you use? Mark.

So I succumbed to temptation and purchased the Martin Pugh 27 hr LHaRGB dataset from Chile taken with a Planewave CDK 17. I'm not sure whether I should have done this, but for added effect I added in the 8.5 hrs of Starbase RGB data to give 35 hrs total integration. I think I have sated my appetite for this galaxy, at least as far as using third party data goes.

I can connect my CPC 800 XLT to CPWI without any problems, however if I connect my celestron auto focuser the focuser is recommended but the mount no longer communicated with CPWI.

Downloaded and tried Graxpert for the first time today. The noise reduction and everything else works very well for me (standalone Windows version). Why not add sharpening and star reduction as well? You know you want to 😃

What he said ^ 🙂 It matters most how the telescope supplied to you works and that there is sufficient redress if it does not work as expected. Steve

Apologies, I was thinking catadioptric was another term for a spherical mirror If I find a very cheap one locally I know what to look out for now ty

I had intended to have a go at the Owl Nebula this session, however rather embarassingly after half an hour's searching I was unable to find it in the eyepiece.🤣 Instead I tried to improve on my previous attempt at M82. This is 800 x 400ms exposures, at 60% gain. And here's a bonus pic of procyon and its spectacular diffraction spikes:

Catadioptric has refractive glass element in optical train next to mirrors - usually as front aperture corrector - making tube closed. Sometimes this element sits inside focuser or in front of secondary - but then you'd have very short tube (Bird-Jones design) or Ruten Maksutov type (but you have newtonian, so it's not that). If it's a longer tube - greater chance that it's spherical mirror. Fast telescopes and spherical mirrors don't get along. If it's F/8 or slower - then it might be spherical.

Thats fine, however I think over companies offer a minimum value (tolerance), instead of offering an actual value.

The tilt adapter would sit between the camera and diagonal. Typically the camera screws into one side of the tilt adapter and a 1.25” nose piece would screw into the other. The nose piece is then inserted into the diagonal. You have two potential issues. 1) the asi120 is prone to newton rings. Even with a tilt adapter there are comments on other forums where even the maximum tilt in the adapter wasn’t enough to remove them. 2) I haven’t seen a tilt adapter that fits a mini version of the asi cameras. That’s not to say there isn’t one, I just haven’t seen one. Like Elp, I am of the opinion that flats will not calibrate out Newton Rings this is because they appear in the flats too. To capture flats I would point the Lunt towards the centre of the Sun, remain in focus and put an opaque plastic bag over the front of the scope secured by an elastic band. Something like a crumpled sandwich or freezer bag works but it needs to be clear/whiteish. Pull the bag tight. Then adjust your exposure time so that the histogram peaks around the 50% mark and capture your frames, say 100 in SER format. In Autostakkert you can create a master flat and open the SER file. Autostakkert will then stack and produce a master flat in tiff format which you can then load into Autostakkert to calibrate your images. Hope that helps. John

Hi Elp, yes filters in the B600 diagonal.

This is the Gassendi crater and the Mare Humorum. Taken with my TAL 2M, ASI120MC-S ( 1 x 2 minute video using ASICAP ) and processed with PIPP, AutoStakkert and Registax with some tweaking in GIMP. I had hoped to use a 2x Barlow to get a more detailed view but the seeing was very "wobbly" and I didn't think that the image would be as good. I also like the composition of this one with the view of the whole Mare and the transition from bright sunlight at the top right to dark shadow at the bottom left.

Ty for this. I meant more how would I know from looking at it? Big aperture shorter tube length would suggest not spherical/catadioptric? Or the opposite? Or neither me trying to collimate it would be something I'd only try on a non spherical newt? Only for the possibility of imaging with it.

I've used 4 and the best one to avoid the most frustration and have a pleasant PA experience is the WO one bar none. If you're patient they do come up for sale used quite often. Second would be the ioptron one.

Does anyone have an (Excel) example for accurately calculating the equation of time value through a whole year? Less accurate example attacheed. Thanks! Anton (www.astronomy-morsels.ch) Equation of Time V1.0.xlsx