What would a good size Ep be for viewing andromeda and nebulas
As the title says I'm after Ep information I really want to view andromeda galaxy and would like do know what kind of Ep would be good I have a 32mm 2" wide view Ep would a higher mag be better like a 15mm? I also after info for nebula viewing too
For my 10" dob, 35x magnification (34-35mm ep) is the optimum to be able to see it at it's best. The higher magnification you go, the dimmer the gas/dust is. A 32mm ep will be a little dimmer (37.5x magnification), but visually you would not really tell the difference.
Either way, it is some 190" across (3.1 degrees in the sky), so you won't get the whole thing in your ep. Maybe at most 2 degrees? Generally, your finderscope can see 5 degrees.
FYI, it's transit at the moment is about 4am. So that will be when it is at it's current highest in the sky, but that is still very close to the horizon.
Hope that helps,
Joel
Last edited by JoelyE95; 29-07-2015 at 09:45 PM.
Reason: Corrected an error
Personally, M32 (the Andromeda Galaxy) is not that exciting. In a moderate scope you really mainly just see the core, hints of the halo and M31 and M110. Lots of more interesting targets IMHO.
Best thing to try for with M32 is getting it naked eye, which can be a bit of a challenge down here in the Antipodes or in binos, I have nabbed it in 10x50s and it was a more interesting object than in my old 12".
As for eyepieces, what ones do you have at the moment? My usual advice to beginners is that unless there is something seriously wrong with the eyepieces that came with the scope, try using those first before spending $$$ on new ones. Several reasons for this:
1 some beginners simply find that astronomy is not for them
2 the low power EPs supplied are usually of reasonable quality and will give fine views without spending money
3 using the supplied EPs will give you a quick education in what the effects of increasing power are if you have a range of EPs.
4 having used them you can make a better informed choice based on your own experience rather than what some one else thinks.
Personally, M32 (the Andromeda Galaxy) is not that exciting. In a moderate scope you really mainly just see the core, hints of the halo and M31
Malcolm
The Andromeda Galaxy is M31. M32 and M110 are the companion satellite galaxies.
Thanks for info. My scope I got 2nd hand with no eps I have a 2" 32mm wide field a 12mm cheapo and a 9mm plossl. I'm thinking on the weekend of looking at a decent brand 15mm plossl maybe. I always have a 2x barlow
Personally, M32 (the Andromeda Galaxy) is not that exciting. In a moderate scope you really mainly just see the core, hints of the halo and M31 and M110. Lots of more interesting targets IMHO.
Best thing to try for with M32 is getting it naked eye, which can be a bit of a challenge down here in the Antipodes or in binos, I have nabbed it in 10x50s and it was a more interesting object than in my old 12".
I agree that a dob is not necessarily the best instrument for this object. M31 is an excellent target for small scopes and binoculars. What you want is a decent exit pupil combined with a wide true field. If feel only then can one appreciate its shape and enormity, and it's certainly more interesting than any of those marginal edge-of-averted-vision fuzzies that DSO-hunters obsess about
I attach a shapshot of M31 as seen from about 44° South, in NZ's South Island just before it set behind the mountains. That view was pretty special through the 60mm refractor - half a galaxy sticking out from behind the ridge. You should have no trouble seeing it from Vic.
Thanks for info. My scope I got 2nd hand with no eps I have a 2" 32mm wide field a 12mm cheapo and a 9mm plossl. I'm thinking on the weekend of looking at a decent brand 15mm plossl maybe. I always have a 2x barlow
Recommended good buy for all users are the 15mm and 20mm GSO Superview (SV) EP's. Many on here have and use them and bang for buck they are excellent. I have both, I'd recommend the 20mm if you just get one. But with a decent 2x barlow and both you have a good range of magnifications for a reasonable price.
Sorry did just check bintel and saw both come in 1.25"
Back to my earlier question would I be better off looking at andromeda through my 75mm newt than my 10" dob?
I have a small Nat geo 75mm newt with a few cheapo eps it came with. Would that be better to view andromeda
Probably not. If those included EPs are anything like the ones that came with my NatGeo Aldi dobette, they are utter junk. You will need an actual eyepiece for this exercise. A plossl or wider, and maybe about 15x of power. Not sure about the focal length of your newt, but I suspect none of the eyepieces you have for the other scope would work. The 32mm would be the most likely candidate, except the newt probably won't accept 2". With the gear you have, the 32mm in the 10" is your best bet I think. Failing that, a pair of 10x50s if you have access to one. Some finder scopes can work well too. Reasonably dark skies are mandatory if you want so see more than the core, regardless of what you use.
One or two darker features of M31 you can probably tease out more easily with the dob, but to me it's the overall appearance that makes this object special. And low power is the way to go for that.
Mirko I don't touch the eps that came with the Nat geo. Saturday I'll be visiting bintel and getting a 20mm 25mm and maybe a 6mm for planets. At the moment I only have a good 32mm and 9mm
From the title of the thread its obvious Adrian is after a low power wide field eyepiece to view M31 and other extended objects within the field of view. That's fine.
However I want to add a little on what can be observed within M31 as a couple of posters have alluded to the fact that M31 is a fairly featureless target and best viewed in binoculars, or a smaller telescope to maximise the FOV and frame the target. That's fine if you don't want to see much detail in the target and frame it as an extended object within the FOV.
There is in fact a wealth of detail and features to be observed within the structure of M31 in telescopes of 10" aperture and larger. The critical thing is dark transparent skies and good seeing.
There are several dust lanes within M31 which are very easy to see in a 10" telescope. In bigger telescopes a few more dust lanes become apparent. I am also attaching a map of M31 which appears on page 16 of the Night Sky Observers Guide. This shows over 40 individual targets within M31, including globular clusters, open clusters and stellar associations. The quality of the photograph, by todays standards, is very poor as it was taken years ago on film, but as a map it is accurate.
Several of the targets on the map are visible in a 10" telescope under good conditions by a skilled observer, including NGC 206, G76, G233, G252, G280 and C107. I have observed 15 of the targets listed on the map in my 14" SDM and over 20 of them in my 18" Obsession. It takes patience, perseverance, very good conditions (ie. good seeing combined with good transparency combined with dark skies) a good telescope with good optics and a bit of skill.
Importantly, you need to change your approach to observing these types of targets as they are extra galactic. The same thing applies to a slightly lesser degree when observing targets within the Magellanic Clouds, but they are much closer than other extra galactic targets, being 175,000 and 200,000 light years away compared to M31 which is 2,500,000 light years away. Many of us are accustomed to viewing globular and open clusters within our own galaxy. This is pretty easy as most of them are bright < mag 10.0 and fairly large where their dimensions are measured in arc minutes. For instance 47 Tuc and Omega Centauri are 30' and 36' across and both naked eye targets. Extra galactic globular clusters and open clusters are measured in arc seconds. Most of the targets on the map are between 1" and 4" wide. Consequently you need good seeing (tighter than the size of the target) to be able to determine them as non stellar. Whilst they are not resolvable in amateur telescopes, you can determine most of them as non stellar. The other thing which is really important is to use medium to high power. This helps to resolve them as non stellar by expanding the apparent size of the target and it also helps to improve the contrast. To properly observe detail and structure within galaxies you need to crank the power up. In my 14" I will often push the power up to somewhere between 250x and 350x and in my 18" scope I will push it up to 350x to 500x.
At 500x, you are not seeing, like, 95% of the Galaxy, are you. A bit like looking at Omega Cen and saying you are observing the Milky Way.
Joking aside, that map is great and will come in handy next time I look at it under good skies. I'd agree that what John says will provide lots of fun for the OP.
Bottom line: Any size scope will show some interesting aspect of this magnificent object..
