wimvb

So, how many dust particles does it take before performance is affected? Imo, return the scope for a full refund, then buy one from a reputed dealer.

I assume that your camera doesn't allow you to change lens, and you can't use it with a telescope? To advise the best way forward, you will need to do some planning. With your current camera, a tracker mount (tripod is just the legs which the mount stands on) such as one of these is the most logical next step. https://www.firstlightoptics.com/star-tracker-astronomy-mounts.html Even if you invest in a telescope and more suited camera later on, you can learn a lot and have fun while being under the stars. Star trackers such as these, can handle up to a small telescope with a dslr. Otoh, if you have a large budget, that will open up for a completely different setup. A motorised equatorial mount with telescope and camera (dslr or astro camera). Anyway, invest also in this https://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html

Dust in your light path is just like any other obstruction, it will decrease the light throughput (aka dust bunny if it's close enough to the sensor) and spread light by diffraction. Both effects will decrease contrast. If it's as bad as your pictures show, I would never be happy with this scope and contact the dealer for a replacement or a refund.

Aladin can cure that problem. 😁 https://aladin.u-strasbg.fr/

👍🏽 Just remember that polar alignment using the polar scope will get you in the ball park, but you need to refine it. Both NINA and PHD have tools for that. Aim for a polar alignment within a few arc minutes.

Correct. Just do a good polar alignment.

+1 for Telescopius. You can create your own catalogs with favourite objects.

I stand by my previous suggestion. 🙂

Diameter of mote/aperture =distance from sensor/focal length Where all units must be the same. Diameter of mote = nr of pixels across x pixel size. Motes that are smaller are usually on the camera cover glass. This mote is very likely on the filter.

Stf tries to apply a best histogram stretch based on black level, white level, and image statistics. Any noise reduction will change the numbers that are used for the stretch. But you can always change the stf by opening the stf tool and moving the sliders. You may have to zoom in on the stf tool.

Excellent image. Use the camera at a constant temperature and gain setting. This will make calibration and stacking easier.

Thanks, Göran. LEDA numbers are the same as PGC (principal galaxy catalog) numbers. It's just that the SIMBAD database uses LEDA and not PGC. If you get bored, you can read up on this: https://www.aanda.org/articles/aa/abs/2003/47/aa3772/aa3772.html

I just googled "Lynds Dark Nebula catalog". This came up as the third hit. http://www.ukcloudmagnets.co.uk/wp-content/uploads/2019/05/Lynds-Dark-Nebulae-Catalogue.pdf

IC 365, also known as Arp 213, is a spiral galaxy in the vicinity of the better known "hidden" galaxy IC 342. It is located in the constellation Camelopardalis (the Camel). The galaxy appears red in colour, because, like IC 342, it is situated behind the dust of the Milky Way, at a distance of approximately 50 Mly, about five times further away than IC 342. IC 356 therefore appears smaller and dimmer than it's neighbour. The spiral arms and dust lanes in IC 356 are very faint, and took some experimenting during processing. Scope: Sky-Watcher MN190 on AZ-EQ6 with OAG (ASI290 mini) Camera: ZWO ASI294MM Pro with Optolong 31 mm LRGB filters Data: RGB: 3 x 40 x 2.5 mins L: 115 x 1.5 mins Total integration time: just shy of 8 hours Most of the data was collected during gaps in the clouds in late december, with the moon all to bright. I had to toss all the data of a second night because of moon light and thin high clouds. All processing was done in PixInsight. This image was difficult to flatten, as my Green and Blue filters suffer from internal reflections. I have now turned the filters around, and test flats seem ok.

Never mind the clouds. The boxes alone would be an environmental disaster.

You probably caught quite a few more Lynds objects. First four columns: LDN number, Barnard's number, RA, DEC.

Great result for only 80 minutes. But as you already said yourself; it could do with more data. LDN1407

Start with using the guiding assistant and use the recommended settings. Also make sure that everything is bolted down firmly, ie no movement between guidedcope and mount at all, and no finder guider in your finder shoe on the scope.

Very nice HH! I guess some astrophotographers do it in their sleep (me included, although not in the garage).

UGC 5247, PGC 28225, LEDA 28225. Not much additional info on this galaxy. It doesn't seem to be part of any group or cluster. Located some 150 MLy distant according to SIMBAD http://simbad.u-strasbg.fr/simbad/sim-id?Ident=UGC 5247

Maybe we should call this the santa nebula. Great image, btw

I still had your image open in PixInsight, and reduced the stars a little.

I use PixInsight. Don’t know if PS has a plug in that removes banding.

My thought was: wouldn't want this on an eq mount. Imagine the meridian flip.

I had a go at your image, and maybe, just maybe, there is a hint of Barnard's loop. There is a very faint red arc left of the flame nebula. But the data is too weak, and as Olly already wrote, to bring out emission nebulas, you need a modded camera. Nevertheless, this is a very nice image. You can try improving the star shapes by stopping down the lens. This will create star spikes, but should give a somewhat better image quality. Right of Rigel, there is a very faint Witch Head nebula, just visible in your image (at least in the processed image on my screen). To bring out this faint signal, you need more integration time, and meticulous calibration, especially flats. If you take flats at a later time, this will risk leaving dust bunnies, but that doesn't seem to be a problem here. Flats will help with the vignetting. And if you guide, dither. Move the camera slightly between exposures, some 12 - 15 pixels at least, in a random direction or spiraling pattern. Stretching also brought out narrow horizontal lines (vertical in the rotated image), that could not be removed by Canon Banding Reduction. This could be bad pixel rows, so you might want to examine the single subs. If they are in all your images, you might consider investing in a new camera.