alacant

Hi We allowed our trial of pi expire;) But anyway... Converted to fits and composed in Siril. Just 2 minutes' processing gets us to this, so looking promising as I think the files may have lost something in conversion. HTH

Mmm. Any better? This is around 23:30... I think the OP should be able to find something in that area.

Hi Recalibrate south, near the equator around say, an hour of the meridian. e.g. ~midnight tonight; anywhere in the 'V' on the top bit of Virgo would be good. Check 're-use calibration' in case you restart during the session. Now slew to your target. That's it. HTH

Stars are without the sw spikes and the telescope holds collimation at all angles, not just the one at which you collimated. Fewer gradients.

Primary mirror. Neutral silicone sealant. A generous blob to coincide with the SW cork. Gouache. HTH

Infinity? It depends on the camera. E.g. most Nikon dslrs will not reach infinity with metal only adapters when using older lenses.

JTOL for similar price point alternatives. There's a Zeiss 200mm on eBay ATM which would be simply mount to camera and go. It's flat, even over full frame. Yes, there's an all metal infinity focus contax to eos adapter for a few € extra. HTH

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There are three other culprits in the push-pull system holding the focuser to the base;) Suerte

With our 130s, so do we (it is however NOT an option for many of our other reflectors), but it looks as though the OP may have flat frame issues, so best to go the official line whilst trouble shooting, the clue being that '...made the vignetting much stronger...'. If you have a short dew shield, you're more likely get away with it. Do you still have the rubber 'O' rings in the focuser? Saludos

Hi If you image with it in place, then you should take the flat frames with it in place. That will probably solve the issue. Otherwise... The biggest improvements for us was a black shower cap over the 1º mirror end, uprated springs, matt black secondary spider+focuser barrel and removing the 1º mirror clips.

Hi everyone. Software marathon. Same image. 3 apps. Can't decide between noise, fat stars or just plain colourless! This is ~3h so there's hope that another 3 may bring something a little less lifeless. I don't think the no-name AliExpress cc helped much. Thanks for looking. --- --- --- --- --- ---

You don't say what focuser you have, but assuming it's the original, then we'd recommend removing rubber the 'O' rings; a recipe for flexure under load if ever there was one. But hey, we're looking at bottom of the range gear. Unless you're looking for perfection and you're going to perform all the necessary modifications, I'd stay as you are. The stars look fine to my eyes.

It looks as though you're too far. We use 53mm cc to sensor distance with our 130pds'. This corresponds to the correct focal length of 650mm. Unless the prescription has changed, the GPU needs the following spacing, depending upon focal length: https://www.bintel.com.au/product/skywatcher-f4-aplanatic-coma-corrector/

Hi Does your 130 hold collimation at all tube angles? We've never seen one which did out of the box. A good test is to inspect frames either side of a meridian flip. A gpu and a heavy camera at that distance from the tube, with the primary loose in its cell makes loss of collimation inevitable, especially with the supplied focuser and mirror cell. Both easy fixes. Cheers

We found 2 issues with the baffle: It makes for fatter stars It does nothing to prevent lateral movement of the mirror as the mount tracks. Our optics guy tells me the former be due to the difficulty in producing a perfectly defined circular knife edge aperture. Most 3d printers leave the baffle with an irregular 90° edge which no amount of matt black will cure I don't think the advantage would be the extra speed, rather the improved star shapes and the ability to hold collimation through all angles. Although of course, every photon you can lay your hands on can't be a bad thing. If you have a cheap refractor, there's a good case for stopping down the aperture. With a reflector, there's nothing to be gained by doing so. Why have a 120mm reflector when you could have a 130mm for no extra cost? Our advice is to go with the silicone. Keep the mirror clips in case you decide to ship the telescope. Cheers and HTH

... and blackened? As too, edge of secondary mirror, spider vanes and nuts which hold the focuser. Matt black. Do the spikes change size or position? Remove the rubber 'o' rings from the focuser. Mirror sealed to its cell? Look down the tube for anything shiny. finger prints etc. But TBH, I wouldn't worry. It's a lovely image. Cheers and HTH.

Nada Brute force and ignorance is the name of the game here!

'Oh, look. It's been done with Topaz.' 'Oh, look. It's been done with StarNet++.' Which maybe could be said of other apps too, but to a much lesser extent. No need to invent or remove stuff though. Any tricking of the eye can be used to advantage using data which is actually in the image you took, as demonstrated admirably by @jager945's algorithms. Arnheim covers this in his masterful 'Art and Visual Perception', 1974 [1]. If I may quote an abstract: Cheers [1] ISBN-10 ‏ : ‎ 8420678740 (Spanish, but translated into most other languages)

Mmm. Did you use Gimp sharpening on your image?

Gimp is nice and the gmic thing gives a vast array of tools, however IMHO, its sharpening can't compete with modern methods of signal processing If you haven't already, try StarTools' SVDecon;)

Nice. The main issue I have with Siril -and I admit to not having looked much into why- is the detail. Almost certainly my lack of patience though!

Correct. Because you haven't stretched it. It is your job to bring it to life by moving it away from where it is. Remember that selecting AutoStretch from the dropdown does nothing to the data. There's also a handy Auto button on the Histogram window if you're feeling lazy. Notice that in both examples, the Linear mode is chosen. But be careful. Do as much as you can first WITHOUT stretching. Here is an example using non colour balanced dslr data from a dark sky:

To decide upon the answer to this question may cost you the price of a round of drinks [1]. If you be so prepared, read on cautiously... Go along to an astro club meeting. Between them, the members will have all the combinations you are thinking about, including those which have been suggested. You can see and try stuff first hand. Read all you like, but in the end, there really is no substitute for hands on. Cheers and HTH [1] Just be careful not to become interested with too many of them;)