wimvb

Yes. Have a look here. It's an extreme example, but it shows the technique quite nicely. https://pixinsight.com/tutorials/NGC7023-HDR/index.html#High_Contrast_Small_Scale_Structures

This past galaxy season I tried to go deep. We moved to a darker location last year, and I built an obsy. So despite the bad weather, I was able to do more imaging than before, resulting in a few images like this. Members of a Swedish astroforum helped me identify some of the "faint fuzzies". They also directed me to simbad. Just passing it forward.

Cliffhanger. 😋

I use Simbad and search either by id or by coordinates. To find pgc galaxies, I replace 'pgc' by 'leda'. http://simbad.u-strasbg.fr/simbad/sim-fid Once I find something, I use the Aladin light link for a visual search. In Aladin I activate simbad.

http://simbad.u-strasbg.fr/simbad/sim-id?Ident=Leda+2571076&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id

The yellow ones are a mixture of quasars, "active galaxy nuclei", and plain galaxies. Some probably a few Gly distant.

Quasars are tiny things that you can hardly see. Until you go looking for them. 😉 Btw 2MASX J15110350+1003419 for nr 3841448 near the bottom. A galaxy with redshift 0.03376. "Only" 444 Mly distant.

SDSS J150958.95+094939.2 -- Quasar?? For the one labeled 4450482 near the top. I did a simbad coordinate search. In fact, I think that most of these are qso's

Duly noted and corrected.

Not even close to yours @Datalord's but otoh only 1 hour of data. If I add 5 hours of L, and a decent amount of rgb ... There's a reason this galaxy wasn't discovered until 2005. 😋

This image makes me even more determined to add colour and more luminance to my UMaI image. I like projects like these, with physics in action on a grand scale.

That "smudge" is a galaxy some 380 Mly distant. The dwarf galaxy is slowly being ripped apart by our own Milky way. According to (one) theory, galaxies form by accumulating matter and stars from dwarf galaxies. So, what we're seeing here as a cluster of stars, are the remains of an ancient galaxy.

If you have zwo cameras, zwo filter wheel, and zwo off axis guider, you don't need any other spacers than those supplied. Zwo have done the calculations for you. https://astronomy-imaging-camera.com/product/zwo-oag

Galaxy hunter is more like it, for me at least. But yes, the Explore Scientific 6" is labeled as such. Here's the MN190 with the 150pds, which is about the size of the ES comet hunter.

Not atm. But there is one at flo. The "lens" in front is a corrector plate which holds a slanted mirror. Since there are no spider vanes, there are no star spikes. Because of the mirror, chromatic abberation is almost nonexistent. MN stands for Maksutov Newtonian.

I would feel comfortable with f/4 or above. But I have some experience with collimation, and I wouldn't care too much if stars weren't perfectly round in the corners. It depends on what you feel ok with. For me, the limit probably lies at around f/4. Filters otoh, especially narrow band, will have poorer performance in fast systems. The better ones may work down to f/3 at best. Below that, the light cone becomes so steep, that the filter characteristics are noticably affected. There is no one firm limit between fast and slow, and what is considered fast, depends also on the telescope model. A f/5 rc or sct would be considered a fast one. A f/5 newt not, even though they are equally fast. With a faster optical system, you can shorten the single sub exposure time. After all, more light per unit time is collected on each pixel, either because of a larger aperture (yay!) or because of a lower "resolution". But I think that if you do a search on astrobin, you most likely won't find a substantially shorter integration time for "faster" systems. My guess is that people will still use the available time, but get better (higher snr) data.

A slower system with two cameras any day. F/2 requires special filters, and you'll be adjusting/tweaking the system so much, you won't have time to do any imaging.

Great catch. These dwarfs are really difficult, I tried the Ursa Major dwarf a while ago. You've done very well.

I love mine. They had a bad reputation as being heavy (but aren't compared to a sizeable refractor), having a poor focuser (skywatcher have fixed that) and being difficult to collimate (not if you leave the secondary where it is, and they hold collimation well). They actually have a lot that speaks for them; a large aperture for their focal length, a focal length that is just in the sweet spot for todays cameras with small pixels, no faffing with flatteners or coma correctors, no critical spacings. If I had the funds, I could imagine buying an eq8 (or a mesu) and another MN190 for a dual rig.

I think I have the best of both worlds, a 7.5" apo-wannabe, a MN190. (Or is that the worst?) 😋

If you hold a lense in front of your eye, and move it slightly, the image doesn't move much. Thank the gods for that, because otherwise us spectacle wearers would have constant headaches. Otoh, if you move/wiggle a mirror slightly, the reflection wiggles double the amount, because angle of reflection = angle of incidence, and image wiggle = sum of incidence and reflection.

Very likely. And with the eq3, the machining is very critical. The mount doesn't have bearings in the ra axis. Its smoothness depends solely on the machining and right amount of "chinese gunk", aka grease. As long as you know the limitations of this mount, and stay on the safe side, it's a wonderful tool. But I maintain, promoting it with a 150pds (750 mm newt) as an entry level AP setup (as skywatcher does), is plain wrong. Maybe at some point in the not too distant future, I'll get an 80ed with an osc camera, and revive my eq3 which I haven't used for a couple of years.

Great first. As said by others: more data never hurts. Longer exposures probably means you have to consider guiding. But if you keep the camera gain high, you can avoid guiding (for a while at least) by using short exposures. But that means lots of subs. For processing, I suggest concentrating on only one software package untill you know that inside out. Then add another if the need arises. In your case, you'll find more information online for image processing in PS than GIMP.

My rig is in an obsy. Mains to the pier where I have a 12V 150W Meanwell power supply. Distributer box, usb3 hub, and Rock64 computer on top of my scope. Before I built the observatory, I had that same power supply hanging off the tripod. All mains plugs away from moisture in a plastic box. I agree, 240 V power supplies and outdoors are not a good combo. Having to dry dew off a lense is one thing, having to wipe it off a power adapter is quite another. But a sturdy plastic box with lid goes a long way.

That should be quite enough for an heq5 and a camera. I wonder what makes a rigrunner so special that you can't use a 240/12 V adapter with it.