The challenge of DSOs

[Capt Slog]

Because I felt I had to have some sort of target when I got my scope, I decided I'd 'collect' DSOs.  It's not easy but then I didn't expect it to be.  It can be frustrating though in terms of results.

Last night wasn't the best unless you wanted look at the full moon, and that just added to the already terrible skies I experience on the Notts/Derbys border with the M1 not far away.  But I decided to look for Bode's Galaxy. 

Okay, I can see where it was supposed to be, but there was nothing there to even get a fix on with the naked eye.  I tried to position the scope by extrapolating the line between Phecda and Dubhe, and then had a sweep around.  Nope, that didn't work. 

I had Stellarium already fired up on the PC indoors, so i came back in and took the  co-ordinates of both Dubhe and of Bode's.  Back outside I then positioned on Dubhe, took the readings off the scales, and then moved the scope by the differences I needed (I'm not set up well enough to point directly).  It took a couple of tries, but the second attempt with a little adjustment got me a fuzzy blob in the eyepiece.  I looked at it for some time, committing to memory.  Later back inside, I checked Stelarium ocular view and confirmed I had seen Bodes. (Rather annoyingly, I then realsied that I might have seen two others in the same field of view but didn't know.)

The frustrating bit.  I checked on that really nice table which ranks the Messiers by V.easy to V.Hard in green to red and found that M81 should actually be quite easy.  But this is something which was barely visible for me.  I'll persevere, but I wonder if I have set my sights a bit high.  Just how far into that table am i likely to get with a 6" scope?

[Kyle Allen]

Charles Messier himself only used a four inch telescope when he compiled his catalogue so your six inch will certainly show you all the Messier objects. He wouldn’t have had to contend with the light pollution issues we face though.

The Moon certainly wouldn’t have helped last night - galaxies and nebulae can be rendered invisible by the slightest bit of light pollution. When the Moon is near full try looking at star clusters (plenty of them in the Messier catalogue) or planetary nebulae (you can tick off M27 and M57 pretty easily) since they cut through the light pollution more easily.

And you’ve just inspired me to make a list of all the Messier objects I’ve observed - I’m sure I’ve still got a lot to tick off! 😀

[Waddensky]

Don't do deep-sky when the Moon is full or even above the horizon, the additional background light will make the brightest deep-sky objects very difficult to spot. Wait for a nice, dark night around new moon. You'll be suprised by the difference!

Not really sure what table you're referring to, but all Messiers are fairly easy in a 6" scope - of course depending on your light pollition levels. M81 and M82 are indeed two of the most prominent Messiers, I can easily see them with my binoculars from a dark site. But they are a bit difficult to find because there are no bright stars directly in their neighbourhood. Bright Messier near bright stars are M13, M57 or M42 for example. Try them out to learn what to expect, then go ahead to find more elusive deep-sky objects. Good luck!

[John]

As above, with a bright moon anywhere in the sky, all DSO's are going to look far from their best and the fainter ones (eg: galaxies and nebulae) will be conspicuous by their invisibility !

Star clusters are a possibility under such conditions, provided that they are not anywhere near the moon in the sky. Even those will not be at their their sparkly best.

Under dark skies a 6 inch scope is capable of seeing hundreds of DSO's though so it's a realistic project.

I first spotted M81 and M82 with a mere 60mm refractor. Apart from M31, most other galaxies are quite a bit harder to spot though.

Under darker skies, try this star hop route to M81 and M82 - it works well !

 

Edited December 30, 2020 by John

[Zermelo]

Does your scope have a Telrad finder?
If so, have you seen this?

[Capt Slog]

Thanks for the replies, they are encouraging in that they say what i expected, ie the moon was the problem.

This is the table I referred to...

This is my spotted list so far M31  Galaxy in Andromeda M103 M57 Ring Nebula NGC 869 Double cluster NGC 884 Double cluster M42 Great Orion Nebula M103 M2 NGC 752 (possible) M81 Bode's galaxy I don't try to find them every time I go out, and i see from the Excel spreadsheet I have them in, that it's the work of about 5 sessions to get those.   I don't have a telrad finder,  I'll post a thread about that one day, you'll laugh at what I'm using

Edited December 30, 2020 by Capt Slog

[Mick H]

I agree with others about viewing Messier's around full moon.

A good book to buy is Turn Left At Orion, which will give you seasonal targets.

This was taken from the online source.

 

 

One of my favourites is M13 in Hercules, but not visible until late spring I think.

I use a Telrad on my 8se and it is quite large, you might be better off with a Rigel Quick Finder on your 6" scope.

Edited December 30, 2020 by Mick H

[Pixies]

The first time I went looking for M81 and M82, it took me about 20 minutes to find them. This was with the basic straight finder on a Bresser 8" dob.

Now, it takes me about 30 seconds, with a Telrad and a big RACI finder. Hell, I can even see then in the finder on a good night.

 

These things take practise and experience. Having a finder setup that works for you helps, too. But with all of this manual finding, you are slowly learning the night sky. Soon, you'll be offering sagely advise to noobs, too  

[Marvin Jenkins]

Hi Capt Slog

What a great endeavour you have embarked upon. Already mentioned, lots of moon really limits DSO hunting.

Don’t forget that some of Messier’s finest are naked eye objects like Pleiades. I had to laugh to myself when reading your OP. You mention M1 being close by, and I thought you were referring to the Crab Nebula but then realised you meant the motorway!

Get informed about the phases of the moon if you are not already (I have a free app on my phone) and happy hunting. Also, be aware that some Messier’s are seasonal.  As you can see from my signature I am 109 of 110 and keep kicking myself that I missed M68 in Hydra. Now I have to wait till early summer and it will most definitely cloudy.

Keep up the good work

Marvin

[Marvin Jenkins]

As an edition look into the Caldwell catalogue. 

[Spile]

On 30/12/2020 at 17:59, Capt Slog said:

I don't have a telrad finder,  I'll post a thread about that one day, you'll laugh at what I'm using

Not with my bad back I won't  - please share!

[michael.h.f.wilkinson]

Over the years, I have bagged all of them, and the majority with binoculars (granted, 15x70 bins). I picked up a large number with my old 6" F/8 Newtonian, but often from fairly dark skies. I also use a RACI (right-angle correct-image) finder scope to star hop to targets, rather than relying on setting circles. 

[domstar]

Well done on your decision to go for the Messier catalogue. Doing the same thing really suited me. It helped me focus on a session and gave me direction and a lot of satisfaction. I have a 4 inch refractor so you'll be fine with a 6 inch scope if your skies are dark enough. Bodes Galaxy and the Cigar are great, but I still find it a bit hit or miss to track them down. It's not an easy star hop. As for the brightness (or dimness) of the galaxies- your eyes will get used to that (on mooonless nights). Things that seem to be just short of invisible will seem a bit clearer with practice. 

Good luck with your endeavour. 

[Capt Slog]

22 hours ago, Spile said:

Not with my bad back I won't  - please share!

Okay, you asked  , but I doubt my solution will ease your back!

first a bit of reasoning and preamble.

I didn't want to spend a lot on my new hobby until I was sure I could actually get into it.  I'd looked a while for telescopes, second hand partly because what I liked seemed to be out of stock everywhere and there were bargains to be had if you looked hard enough.  I eventually managed to pick up TWO telescopes for £60, a 150 Skywatcher on an EQ 3-2 (?) mount and a 4" Bushnell, on Facebook Marketplace.  Very chuffed indeed.

I bought a couple of cheap Plossl eyepieces and I was off.

One of the first nights in the garden, I found it very difficult to position the scope at areas where there were a lot of stars.  Cassiopeia was one I recall, i could see it but as soon as i looked through the finder, there were many more stars visible and they were the wrong way round, i couldn't work out what I was looking at.  It was obvious I was going to need a telrad or similar.  But they aren't cheap (and I am) and I wasn't going to spend effectively the price of my scope, well not yet at any rate. 

 

So I came up with this...

It's exactly what it looks like, a piece of aluminium tube.  The black tapes attach two neo magnets, and these fasten the tube to the scope and I can move and position it in seconds.  I first find an easy target, then move the tube around until the target is centred, then I'm set for something else.

When it looks like this...

...I'm sort of at 'no parallax', and despite it's crude appearance, it's close enough to do the job.  It gets me on the right target so that the proper finder is easy to use.  I did experiment by adding an LED to the tube, to give ring of light, but my skies are never dark enough that I can't make out the tube against the sky.

I will make something more sophisticated in time.  I'm looking at using a piece of optic fibre in a fine tube to give a 'red spot' type sight.

[Spile]

I like it and came up with a similar idea, using a bit of duck tape and tube...

[Roy Challen]

M81/82 are impossible from my town centre location, with or without optical aid, due to severe light pollution. I know exactly where to look, but have never seen them. It used to be frustrating because photographically, even from my garden, they're easy targets. As I now only concentrate on planetary and the occasional double stars, it's not an issue. I save the DSOs for bins and dark sites.

[theropod]

I’ve been reading the thread with great interest. Those of us with narrow FOV scopes can, and do, have all kinds of issues with getting targets in the EP. I just yesterday hung a 50X9 RACI illuminated  dual crosshair Celestron finder on my C90 Mak, and induced a winter storm advisory (snowed yesterday) and have only roughly aligned it to a distant (>2 k) lone pine. The old straight through finder became a pain during 1,2 or 3 star alignment, not least of which was silly thick crosshairs, and the 90° view will save my old creaking neck. I did have to narrow the distance between the mounting screw slots to fit the tapped holes in the C90, but my chainsaw file fit the slot well, and it made short work of the soft cast metal that the finder’s base is cast. I had to start the screws and leave them loose so that I could apply torque evenly to the Phillips head screws. I thought about a locking compound on these threads, but don’t want to have to apply heat/ chemicals to my little scope to get that compound to release should I need it to. Maybe just the torque I evenly applied will do the job. I detect no flexing or rattling. I still need some night time with my dual crosshair EP in my main scope to zoom in on a particular star, then make the same reticle type finder match. The Celestron “springy” adjusting system still relies on a O ring in the front ring, and I may drill, tap and install adjustment screws to replace it. It isn’t hard to do, if one is methodical. I also may leave well enough alone, and stop inviting a new glacial maximum.

[wobblewing]

Nice thread,  I'm glad you posted this - I'm going through the same pain!

We have Skywatcher Hertitage 150p on dobsonian mount....  Only been out a couple of times due to cloud.. but it's been very bright moonlight so have struggled to find anything.. Just about got a mush for Orion's Nebula.. and bagged The Seven Sisters... that's it so far... couldn't find Andromeda!  No problem viewing the moon 😄

 

 

 

Edited January 3, 2021 by wobblewing

[Tiny Clanger]

26 minutes ago, wobblewing said:

Nice thread,  I'm glad you posted this - I'm going through the same pain!

We have Skywatcher Hertitage 150p on dobsonian mount....  Only been out a couple of times due to cloud.. but it's been very bright moonlight so have struggled to find anything.. Just about got a mush for Orion's Nebula.. and bagged The Seven Sisters... that's it so far... couldn't find Andromeda!  No problem viewing the moon 😄

 

 

 

Hah ! I had the exact same problem: heritage 150, suburban back garden, , M31 fail...

Then one summer night (I can't get up to check which night in my observing log sorry the cat is asleep  on my lap ,  and she doesn't appreciate being disturbed) I went out without my 'scope and settled down on a camping mattress on the lawn to look for meteors ... after a couple of hours averted vision accidentally showed something grey fuzzy and vague roughly where M31 should be, so I got the binoculars and there was the blighter !

Next night, filled with confidence I trained the 'scope at the fuzzy thing .... and a ridiculous pantomime of averted vision seeing it, then use of the RDF requiring looking directly at it, then having no idea if the red dot was near the grey fuzz because averted vision plus RDF is (for me anyway) impossible , and repeat ... In the end I gave up, and got the binos out just to prove to myself that the thing was still there in the sky.

And that's when I decided a 6x30 RACI was a must have ...

 

Edited January 3, 2021 by Tiny Clanger
terrible syntax and punctuation

[wobblewing]

Glad I'm not the only one then 😄

 

[gilesco]

As I peruse the sky these days looking to decide whether to set up kit or not I often spot M31 as a fuzzy bit of sky when it is crisp and good. I guess you only notice it when you know exactly where it is and when you've viewed it before through a scope etc.... once you know what to expect to see it becomes easily recognisable.

[wobblewing]

BTW Which finder did you go for , to fit it to the Heritage 150p dob?

[Tiny Clanger]

2 minutes ago, gilesco said:

As I peruse the sky these days looking to decide whether to set up kit or not I often spot M31 as a fuzzy bit of sky when it is crisp and good. I guess you only notice it when you know exactly where it is and when you've viewed it before through a scope etc.... once you know what to expect to see it becomes easily recognisable.

Yep, it's always there for me now, a constant reminder that persistence pays off ,  and  buying a telescope is not enough, time and patience play a big  part.

4 minutes ago, wobblewing said:

BTW Which finder did you go for , to fit it to the Heritage 150p dob?

6x30 skywatcher RACI, , it cost  about £35, to add it to the dob I got a £5 shoe from the far east and stuck it on the solid tube near the pivot , so putting it on or off doesn't mess with the balance.  it's quite heavy, having a solid metal bracket. I used sticky pads to fix the shoe on, one day I will feel brave enough to drill the tube and bolt it on properly ...

The RDF mount on the front of  the 150 is not a standard shoe, so  I've left the RDF on there, it's still very useful for lining up objects I can actually see ...

Heather

[wobblewing]

Thanks for the tip!

 

[Tiny Clanger]

By the way, I've posted this before , but you may have missed it : a pdf downloadable messier log which rates objects by their difficulty in both binoculars and 'scopes:

http://astrowolf.at/wp-content/uploads/2015/10/Objektkatalog_Messier.pdf