What are "bright" DSOs, really?

[josefk]

Though the descriptions are OK my tongue was firmly in my cheek when posting @SwiMatt

To your original question if i sort my observing notes by 'calculated surface brightness' in MPSAS (quite imperfect in lots of ways but better than nothing) and then "eyeball" the list, then there are several hundred entries for Planetary Nebula, Open Clusters, & then Globular Clusters before even bright Galaxies make an appearance...(or not as the case may be 🤣) The first bright galaxies then in the list are with only a few exceptions Messier objects. 

Obviously thats a very subjective comment based on what i attempt to observe but it chimes with what others have posted above.

Edited June 1, 2023 by josefk

[SwiMatt]

15 minutes ago, josefk said:

Though the descriptions are OK my tongue was firmly in my cheek when posting @SwiMatt

Hahaha yes, the dry writing made it hard to convey that I was also answering tongue in cheek!
 

Quote

To your original question if i sort my observing notes by 'calculated surface brightness' in MPSAS (quite imperfect in lots of ways but better than nothing) and then "eyeball" the list, then there are several hundred entries for Planetary Nebula, Open Clusters, & then Globular Clusters before even bright Galaxies make an appearance...(or not as the case may be 🤣) The first bright galaxies then in the list are with only a few exceptions Messier objects. 

Obviously thats a very subjective comment based on what i attempt to observe but it chimes with what others have posted above.

I guess the main point of my question (which has been answered now) was whether a beginner in typical city location with limited aperture (say anywhere between 90 and 150 mm) is limited to see the moon, the planets and 3-4 smudges, or whether the number of (averted) visible smudges was in the tenths or even hundreds. Whenever I read "you can see the moon, the planets and the bright DSOs" it sounded like the former, but it seems like lots more can be done even under polluted skies. And I expected lots of subjectivity, but the general answer seems to be "you can see lots of stuff, with time, experience and a bit of luck".

[josefk]

33 minutes ago, SwiMatt said:

"you can see lots of stuff, with time, experience and a bit of luck"

100%

[Elp]

Remember where you saw it first:

[Elp]

Id say from my bortle 7 via my C6, closed clusters like M13 are S10A.

[jetstream]

6 hours ago, F15Rules said:

Q. "What are "bright" DSOs, really?"

A. They are easily visible small grey smudges, as compared to barely visible, wispy grey smudges.

🙂

Dave

Lol!👍

A faint fuzzy is a faint fuzzy no matter the aperture. Oddly enough I really enjoy bright DSO in my 24" ie ones that are bright in my 10" - the difference is staggering.

[jetstream]

7 hours ago, SwiMatt said:

But I would disagree that spotting at this level remains a tick exercise

Well I agree with @Piero- I still do tick exercises, but eventually one starts to realize that the tick list is endless lol the bigger aperture and the darker the skies the list becomes so large ....

During my 'tick" phase I did discover some objects that have become favourite go to mainstays ie the IC1318 complex, the "Little Veil" nebula complex, SH2-94, the Foetus neb and Hickson 55 plus so many more.

As far as observing under LP skies and with small aperture, it really is a tick exercise IMHO.

[FenSkies]

3 hours ago, SwiMatt said:

I guess the main point of my question (which has been answered now) was whether a beginner in typical city location with limited aperture (say anywhere between 90 and 150 mm) is limited to see the moon, the planets and 3-4 smudges, or whether the number of (averted) visible smudges was in the tenths or even hundreds. Whenever I read "you can see the moon, the planets and the bright DSOs" it sounded like the former, but it seems like lots more can be done even under polluted skies. And I expected lots of subjectivity, but the general answer seems to be "you can see lots of stuff, with time, experience and a bit of luck".

My very much beginner experience with a basic 90mm/910mm achromat, is that the smudges are at least in the tens under my variable (apparently Bortle 5) skies. M1, The Crab Nebula, is just about visible with direct vision (once found) under crystal clear conditions with a 90mm but I have only found it three or four times in as many years. M81 and M82 are easy, as are the main globular clusters and many open clusters. M103 can be a little jewel box on a good night. The Leo triplet of galaxies are not  difficult with direct vision. M57 is easy and shows a little colour at 90mm. Owl nebula, surfboard galaxy, star clusters in Auriga etc.