Finding problems

[Mathyas]

Hi guys,

I have a serious problem with finding deep-sky objects. Im living next to city so the sky is slightly light-polluted from one side but dark from the other. But i still have problem to find anything at all. Only deep-sky object that i found was M13. Tried to find something like California Nebula, but failed. Tried to look for M97, M109, M108, but again with zero results. I have only 2 eyepieces (standard SW 10mm and 25mm) that came with my telescope(Dobson 8" which i have for 4 days)

Is this common problem, or am i stupid?

[cloudsweeper]

Clusters should be easy, some galaxies perhaps, and nebulae maybe a little harder.  A longer focal length EP might be beneficial, as long as the exit pupil is not too high!

Doug.

[Mathyas]

1 minute ago, cloudsweeper said:

Clusters should be easy, some galaxies perhaps, and nebulae maybe a little harder.  A longer focal length EP might be beneficial, as long as the exit pupil is not too high!

Doug.

I would like to buy 2" 38mm 70° SW. Will it help me?

[Peter Drew]

You're not stupid and it is a common problem. Apart from M13, the other objects you list will be very difficult in light polluted conditions. Try M92, M57, M27, M15, M31, these are considerably brighter.

[BXRO]

Think you need to get your eye in, objects can be very elusive untill you first see them and you know what you looking for, you can then often go straight to then after that. I would recommend the beehive cluster in Cancer for a first look, the double cluster in Perseus or M35 in Gemini so that you can get some idea what your looking for. You really won't want anymore than 35X magnification to see them and do them justice

[domstar]

Hi. Yes I agree with open clusters. It took me ages just to find Jupiter. If you have stellarium, and can find naked eye stars in the finderscope, try finding a dso that is in the same field as a naked eye star. Then you can be (reasonably) sure you have the right place and just wait a while at the eyepiece. Good luck.

[John]

As Peter says above, the objects you list are pretty challenging, most needing dark skies and some special filters to see. Have a look at some of the objects that Peter lists and you should have more success

 

[Charic]

9 hours ago, Mathyas said:

But i still have problem to find anything at all.

Scope only 4 Days old! 

Is your scope fully collimated, aligned and cooled? 

Having these in order will help, as does having the right viewing conditions and a street light pollution free viewing site!

I for one can just make out the small central core of Andromeda M31 from my garden, but from a darker site, M31 totally fills my view, such is the difference between site conditions.

For collimation, either one of these guides will suffice, but read both, to fully understand what you have to try and achieve.

http://garyseronik.com/a-beginners-guide-to-collimation/

http://www.forumskylive.it/Public/data/serastrof/201281510358_Astro Babys Guide to Collimation.pdf

Aligning is just focusing the telescope on a distant tower or similar ( on the horizon will do?) then when in focus, lock the scope tight, then adjust the finder scope to align to the same target, but don't move the scope, just the finder  using the finders ajustment screws. When fully aligned, searching the night sky through the finder with both eyes open? becomes easier using the standard 9x50 finder scope, then if/when you find a target, the image through the eyepiece will also be on target!

The cooling bit is simple, where you store the scope is possibly warmer than when your outside using the scope. Allow the mirror a cooling period of say 30 mins + and the images produced become sharper after a while. Its due to warm air over the face of the mirror, like looking though a heat layer, destroying the basic image. All Newtonian scopes suffer from this, if there's temperature difference between store and in-use.

If you can see the Moon ok and maybe some Planets and/or the Stars clearly, then I will assume your scope is correctly setup, therefore your seeing conditions are letting you down. Whatever the issue, lets hope you get it sorted soon. 

[Mathyas]

2 hours ago, Charic said:

Is your scope fully collimated, aligned and cooled?

Yes. Its collimated and aligned. I leave it outside for like 40 minutes before i go out. Even if i look in the direction of deep-sky objects, i dont even see any signs that im in the right spot. For example. I tried to look at the spiral galaxy and planetary nebula at the merak star in ursa major. I think i was in the right place and tried to search for it, but without any results.

Maybe i was looking at the wrong spot?

[wookie1965]

I too struggled to find deep sky objects until a a friend who is a lot more experienced than me told me to go for clusters and double stars, only the brightest galaxies can be seen from light polluted skies (M81,M82,M45,M42) to name just a few. get a good map. Since i have done this I have seen countless objects and renewed my love of this hobby.  If you want to see deep sky objects you need get out of town in dark skies hope this helps. 

[cloudsweeper]

Check that the exit pupil is around 3 or 4mm - divide EP focal length by telescope focal ratio.

If the figure is too high, there will be poor contrast in polluted skies, making it hard to spot faint objects.

Doug.

[happy-kat]

Also objects can't be seen if looking straight at them but only sight with averted vision. It's like your peripheral vision sees the object and then disappears when you look straight at it. This is how m57 is for me.

[sockgoblin]

it also helps if you appreciate just how faint these objects are. Sometimes they appear as a very very faint grey smudge easily missed or dismissed as a floater or bit of mist or cloud. As you look at the area for a longer period of time the details tend to begin to pop out.

The quality of the sky varies even in light pollluted skies some nights are better than others

I have seen the Ring Nebula as a very faint disc but I only suspect that I can detect the ring and then only with averted vision. I can see two of the Leo Triplet galaxies as round blobs but cant see the third. I can see the Whirlpool Galaxy as two faint ovals but cant see much of the spiral arms.

In my skies galaxies and nebula are underwhelming and quite frustrating ,and if my only targets can make for a disappointing night, but clusters, doubles , planets still have that wow factor.

A good book that has realistic images of target and finder maps is the  Illustrated Guide to Astronomical Wonders by Robert Bruce Thompson and Barbara Fritchenman Thompson

[sockgoblin]

I also have an 8 inch dobs and I found the best additions to help locate objects were

A pair of 8 x 40 binoculars.

---A telrad finder

---A Right Angle Erecting Viewfinder ( gives a more comfortable upright view )

---A 32mm  eyepiece ( but you could use you 25mm EP)

---The Pocket Sky and Telescope Guide ( I also have the Jumbo sized one , same maps but easier to read)

Later I added some setting circles but best to use starhopping first to learn the skills.

Planning before the session is important use the Sky guide to locate some bright stars near to your target and decide which route you are going to take to the target. I use the Telrad to aim the scope to a bright star near to my target then use the Finder scope to starhop to where it should be then the 30mm Eyepiece to finally nail the target

You will get better , the first few sessions were difficult but it will come to you.

[Nyctimene]

Your problems seem to be related to the low surface brightness of the objects on your list, as Peter mentioned above. The visibility of these objects suffers very much in light polluted areas. M 97 and 108 can be very tricky even for experienced observers. I'd suggest you to start with open clusters and globular clusters, e.g. M3, M13 (which you've spotted), M 92, M44, M 67; later on M4 and M 80. If you want to spot galaxies, try M81/82. Make yourself familiar with the terms of surface brightness, and try to get  information on this for your observed objects. I'm using the Night Sky Observer's Guide (very recommendable), as Stellarium and SkySafari don't give the values.

Sockgoblin's list of additions above is spot on!

Try to take your Dob to a dark sky area; here's a map:

https://www.lightpollutionmap.info/#zoom=12&lat=6384022&lon=990748&layers=B0TFFFFF

Take yourself time, a LOT of time, keep asking here, and enjoy the journey!

Stephan

[Davesellars]

Personally, I don't think M81/M82 is an easy one to star-hop to for the beginner.

What finder are you using?  Star-hopping, like paying out for GOTO needs a bit of investment - not only in time but in the tools.  But, with time you'll be finding objects quicker than any GOTO system    A RACI 50mm finder for me is essential as is something to point to a star or area in the sky in the first place like a Telrad or Rigel Quickfinder  A star chart showing sufficiently low magnitude stars and enough detail is also critical.  I use SkySafari on an iPad, others prefer to use a paper map.  There are quite a few options and some you can download and print out for yourself.

Your failures on those galaxies will be two-fold - not knowing how to see faint objects and most probably you're looking in the wrong place.  For a very faint object, you need to know exactly where it is.  It takes time to train the eye to see faint objects and even more to be able to see detail within those fuzzies.    With those objects you listed you're trying to run before you can walk as with 8" aperture they're most likely going to be at the limit of vision if the LP hasn't drowned them out completely.

It would be useful to know the lowest magnitude star(approximately) you can see naked eye.  With this you can then at least choose objects that are suitable for your skies and aperture.

When you begin to learn to star-hop to objects.  Choose objects, not only that are reasonably bright (globular clusters as mentioned are a good choice) but also that are reasonably near a bright star that you can see naked eye.  Look at the chart work a out a route to the object using other stars (patterns of stars) that you'll be able to distinguish through the finder.  Take it slow.  If you fail, go back to the start and try again.

Galaxies: for easier ones that are closer to stars that are reasonably bright (so a nice obvious start).  I'd recommend M65 and M66 in Leo.  M51 is also reasonably bright and a very short easy star hop from Alkaid in Ursa Major.

[ronin]

Very likely you are the same as everyone else has been at some time. Aiming a scope is not the easy simple thing that it is described as. DSO etc tend to try and hide as much as possible also.

If not already done then align the finder as well as possible, however you may just as well find the finder not easy to use, The supplied one is often a straight through item and many find those difficult. You have to put you hed on the tube and sight along it.

Search out a few easy DSO's, Stellarium, F4 and set the DSO magnitude to 6 or 8, good practise for the not easy DSO's. Also remember they do not look anything like the Hubble images of them.

Suggest you have a few possible ideas to go look for but mainly just use the scope, find those big red stars - they stand out when you sweep across them. M1 could be waviong a flag and you would miss it. 4 days with a dobsonian is not long, I would expect that you need 2 weeks of getting to used to moving it around the sky from star to star and object to object before you become "comfortable" with it. Then things should be easier and better.

Not sure if I would say get an eyepiece or two, you will eventually want some, so maybe consider a wide Plossl (30-32mm). Half a reasonable idea as the extra field is useful, and the supplied items are basic. Your decision but this hobby is meant to be fun, and seeing thing is really the fun bit.

Can you point the scope at the rear end of Leo and a bit more away from the body, there are lots of galaxies there, all you see is lots of small disks (I mean SMALL) but it is a field full of them and gets something under your belt.

Ursa Maj is fair for some, a few around the srtars of the pan/plough. Basically find star and hopefully the faint dim galaxy may be in view. Still suggest just getting used to the scope and I think that will be a while yet.

[JOC]

1 hour ago, ronin said:

Still suggest just getting used to the scope and I think that will be a while yet.

Agreed - I've used mine around 10 times so far and the only nebulous looking faint grey fuzzy I've viewed is M42 in Orion and you can't really miss that one if Orion is up there as on a clear night you can practically see it with the naked eye.  I tend to think there is a bit of a black art to viewing faint grey fuzzies.

Edit:  Should that be a 'grey art'?

[Macrob1]

On 4/27/2017 at 00:24, JOC said:

Agreed - I've used mine around 10 times so far and the only nebulous looking faint grey fuzzy I've viewed is M42 in Orion and you can't really miss that one if Orion is up there as on a clear night you can practically see it with the naked eye.  I tend to think there is a bit of a black art to viewing faint grey fuzzies.

Edit:  Should that be a 'grey art'?

From a southern sky observer I agree that Orion is a good place to learn. M42 is more than a grey smudge whereas the nearby M43 looks like a star to me but if you use a UHC filter it becomes a fuzzy. There are also some good clusters in Orion and nearby eg. NGC1980, 1981, 1977 and I reckon a good  open cluster is hard to beat.  Not too much scope slewing needed in this region to see some really nice objects.