alacant

Not so much the primary mirror, rather the silly backfocus; more that half the focal length comes after the secondary. Imagine trying to hold a camera, no matter how light at this distance from the tube, let alone balance the same! Hopefully the sw doesn't have this problem. Yours is looking promising. Good luck and do report back.

Hi Lovely shot. The amount of detail is superb. Love it. Just a thought... With the 533, are you sure it's necessary to introduce more glass? The field is easily corrected in software. Don't know about ps but very easy in StarTools' lens module:

The one you need to begin with is an ir cut. These usually include a UV cut off too. The latter is not needed for your reflector, but neither will it do any harm. Rather than Ha, which will give you monochrome (process in shades of any single colour you like), try a UHC. Links to ir the filters here. UHC from the same source. HTH

Either a clip in filter for your camera or 2" filter + double sided tape:

Hi As @barbulo comments and confirmed on the ground using Siril: drift along DEC. Over 5 minutes, the mount needs to be mechanically perfect, correctly adjusted and with both -very- accurate polar alignment and tracking. Maybe take more say, one minute frames instead? Or you could guide the mount. Cheers and HTH.

Hi We can't tell because we don't know which which adapter you are using. The 200p comes with both 1.25" and 2" adapters. So either This or this.will get you there. HTH

Some ideas: Drill the dovetail plate where you want the bolts to fall Fit a wide Losmandy dovetail plate or. simply... Cheers and HTH

Our cat guy says something like this... Assuming you're in focus with an eyepiece, the camera needs to be between 10cm to 15cm from the rear face of the telescope, probably nearer the latter. You may need an extension tube. HTH

Hi Given the mechanics of an 80ed, I'd say very good. Adjusting from here may make matters worse. For values as close as this, simply reseating the camera or any other part of the train would most likely result in different tilt. If anything, maybe the focus is a little wayward. Best not to use a focusing mask as not all colours coincide in the focusing pattern. To get you close, choose a -not too bright- white star. Look for the minimum hfd value as you rack the focuser.. Now adjust focus -a tiny amount- until the blue halo just begins to disappear.

Hi Amazing amount of detail for such a short exposure. Love it. We'd recommend dithering between frames. If you've around 20 or so, you then stand a good chance of the trails being removed by stacking; use a decent clipping algorithm. Cheers and HTH

Hi I see one frame with elongated stars and another with round(er) stars. Have you had a look at the guide log to see what, if anything, is different between the frames? Over 1000mm, you need only slight protuberances to cause elongation. If not, something is moving during the exposure. EQASCOM already has a capable PEC algorithm, so no need to introduce anything else into the mix. PHD2's PPEC will do a good job of removing the 122s RA oscilation. If you want to get rid of it all, record VS-PEC for 40 minutes when the PPEC guiding has had chance to settle. FWIW, we work the other way around. Before anything else, the mount is stripped, cleaned, rebuilt and adjusted. We then perform a guiding session under INDI to make certain we can eliminate mount mechanics. We find it quicker and with fewer lost frames that way.. We speak from bitter experience! Cheers

Congratulations and well done for having a go with a humble unmodified DSLR. They really are good cameras. Lovely wide shot of a nebula and star field. So much interest and texture is lost by removing the latter. Cheers

Hi Nice shot. To help with noise and other artefacts, don't use camera bias frames. Subtract instead a constant bias offset of 2048. 70d so lose the dark frames. +1 for @barbulo's suggestion for including flat frames StarTools: you've lost quite a bit of data. Go easy with second and subsequent AutoDev. Otherwise, just keep adding to the frame count to make it even easier to process. Cheers and HTH

Hi You've produced some good quality data with which to try differrnt app(roache)s. Here's one keeping the wonderful star-field you captured intact.

Hi I see the triangular stars are noticeable by their absence:) For an eq6 at 1000mm focal length, good. If you really can't live with the elongation, read on. Otherwise, just correct in software. DEC: sudden spikes: This is caused by something mechanical/cable/wind/animal; the DEC motor is not running before the spike. PHD2 tries to correct, but the magnitude of the pulse causes DEC to overshoot: You could try lowering aggression and DEC backlash, but in the end, perhaps the best cure is to dismantle and re-build the mount. If you've ever witnessed the inside view of a low end sw mount, new or otherwise, you'll see why. RA Before dismantling and rebuilding, try PPEC with a fixed peiod of 122s. Unfortunately though, unless DEC issues are addressed, this is likely to make the elongation narrower, so more noticeable. A few last bits: - Do you still have the rubber flex inducing washers (7 off) in the focuser? - Although unlikely due to use of an OAG, steel sw tubes are nortoriuos for flex. Maybe consider adequate support. - It seems you now have the primary mirror cell performing. If not ...etc. - are you certain you have the 120mm after an ir-cut filter? Cheers and HTH

- Enable NFC on the 7200. - Hold your 'phone near the card slot. - Open the app. I'm sure others will recommend their own favorite, but meanwhile this is Nikon's official version. Use the same app to connect from further afield using e.g. your home network or from anywhere over Internet. That's it. Cheers, welcome and HTH

Hi At that focal length (guessing around 1000mm?) any wind, people (and cats) walking near the mount and mechanical imperfection no matter how slight, will cause odd shaped stars. That you have differing star shapes on different frames suggests a combination of factors, so it's unlikely to be only the one you suggest; The mount and associated mechanics -e.g. camera-focuser, dovetail and guide telescope connections have to be better than perfect to give your guiding software a fair chance. The good news is that imperfections such as these will be minimised if you have sufficient frames and use a good clipping algorithm to stack them. It's also a good idea remove any outliers before stacking.. Be ruthless! To help with the latter, Siril has a plot making it easy to de-select frames. Finally of course, stars shape (star shapes?) can be corrected using the psf algorithms present in modern astro-processing apps, some better than others. Just be careful not to overdo it. Cheers and HTH

Hi This is typical of the old d4 firmware. Make sure you're using the latest version. Capture: Dither at least 10 pixels after every frame Our method using Siril: 1. 550d so lose any dark frames you may have used. 2. Pre-process with a fixed bias offset of 2048 3. After pre-processing, apply horizontal banding reduction with highlight protection to the whole sequence before registration.. 4. Stack using a clipping algorithm. Sigma 3,3 is a good starting point. -> super clean image ready for processing Cheers and HTH

Thanks for your comments. We couldn't agree more. Much good data is wasted by the current trend of star removal. This seems to go hand in hand with over-processing. Just because current apps have myriad of try-it-and-hope-for-the-best type modules, doesn't imply obligation to use them all. By way of example, 'de-noise' (seemingly present in all astronomical image processing apps) is one of the main culprits. Especially when applied at maximum volume to the whole image. Stars yield texture and interest. We spend €thousands to enable us to take images of the night sky, then remove one of the most interesting components! Disclaimer: but hey, we're here to have fun, and make art. If at the end of it, you're satisfied, that's all that counts. One visitor was so delighted to see his mount finally respond to guiding corrections that he spent all night just looking at the graph. One man's satisfaction is another... etc. Cheers

Hi everyone Not sure if a UHC filter was the right choice for this. It does however seem to have controled haze from last night's gibbous moon. Gave up trying to do anything with the stars. The more you try, the more edited it looks. Anyway, thanks for looking and do please post your DSLR experiences with this target. Thinking it maybe worth another go without filters. eos700d + gso203 ~5h @ ISO800: siril 1.1.0 git, st 1.8.525-2

Hair dryer, blunt blade and patience.

1.4x12x15 mm: (wire OD L) Fit six. 3 replacements and a further 3 passively over the locking screws. Leave the latter loose. AliExpress: lots of 10 for €sensible. Whilst you have it on the bench, we'd recommend removing the mirror clips. Just our works-for-us approach but HTH anyway.

Hi Is there a reason you can't focus manually using e.g. live view?

Hi A new m10 ratchet bolt? Around €2. HTH

Hi Our cat guy says this one. Solid and with a choice of prisms: You'll also need the imperial to metric adapter. M48 recommended, as extension rings in this size are readily available to adjust the 0.7 to sensor distance. M54 less so. If you're EU, they'll ship from within. HTH