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Best Binocular Choice For Observing The Andromeda Galaxy?

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#26 gwlee



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Posted 24 November 2020 - 01:46 PM

The great galaxy in Andomeda has many facets, it has many secret treasures to reveal. With its extent of several degrees and large dust lanes and companion galaxies as along with faint globulars and nebulae, no one instrument is sufficient for enjoying good old M31..


It's always surprised me how close it's satellite galaxies NGC 147 and 185 are to M31. 147 is about 330,000 light years, that's only about twice as far as M110 is from M31. 


The great galaxy has something for every instrument.



Yes, I viewed andromeda this season using 7x50 and 10x50 binoculars, 72mm and 92mm refractors, and an 8” dob using only one instrument each night and progressing from the 7x50 to the 8.” Each session was 2-3 hours.


I found there wasn’t much difference between the views offered by the 7x50 and the 10x50, or between the 10x50 and the 72mm at this site, so next time, I don’t think I will include the 7x50 or the 72mm in the rotation. 

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#27 ihf


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Posted 20 December 2020 - 10:59 AM

I had a chance to look at Andromeda again under bortle 1/2 skies. The canon 15x50 still showed it better than kowa 6.5x32, but I would have preferred more view than the canon provided. Good reason to have multiple binoculars!

#28 j.gardavsky



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Posted 20 December 2020 - 05:59 PM

Hi ihf,


I was considering the 20x100's for their slightly wider fov but most reviewers said that the 25x100 are a better choice. Something to consider. Dark skies are a must to allow for better contrast ratio. I think Andromeda is 3 or more degrees in length but it would be photographic. Not sure how much length can be seen in the visual? Perhaps someone can provide the data.


I agree that the framing makes for a better viewing experience.


Things to ponder.


Hello Don,


here is a comparison on how the M31 is framed through the 25x100 and 20x100 binoculars,




Among all of my binoculars I have ever had, the best views have been through the old 25x100 FB, showing the outer spiral arm between the M31 core and the M110 dwarf, the NGC 206 Stars Cloud, and a hint of the dark lanes.


The 25x100 are very good galaxies hunters, and there are hundreds of galaxies within their reach.




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#29 daniel_h



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Posted 20 December 2020 - 08:41 PM

agree w jon and mark, my 15x60 4.6 deg is about right for me, but have seen in both 15x70/16x70 -all do a decent job. i have nice dk skies - i reckon under 4deg is selling the extended obj a bit short - also helps with definition detail if you have some black space around imo

i don’t like it with mono, re telescope vision, doesn’t work well for me

#30 Jawaid I. Abbasi

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Posted 20 December 2020 - 11:01 PM


You've not made any reference to the darkness or brightness of the sky you intend to be observing from.  What you'll see will depend more on the darkness of your sky than it will on the binoculars.  If you don't have a dark sky (and most people don't), you'll likely be disappointed in your views -- regardless of the binoculars.


Furthermore, there are plenty of telescopes around that can also show M31 and its companions in just as wide of a true field as an "ideal" pair of binoculars.


Here's a sketch of M31 (and M32, and M110) as observed visually -- from a dark sky -- with a mere 1-inch aperture at 20x with a true field of view of about 3.3 degrees:


"Things" were not as bright nor as easy to see in the eyepiece as they appear in the sketch; but all that appears in the sketch was, nevertheless, seen.
Any pair of binoculars (or telescope) that can provide a similar true field of view at a similar magnification will be able to show a similar view -- if used beneath a dark enough sky by an experienced enough observer.
In other words, getting the "best" view  will require more than just having the right equipment -- something that most people tend to ignore -- until they attempt that first view and are rewarded with disappointment.
On the other hand, perhaps you have a dark enough sky and enough experience . . .
With all that being said, under a dark enough sky, any pair of binoculars will provide a very nice view of M31 and family.  I like the view with my 8x42 binoculars; but my view with 20x80s (3-degree field of view) is preferred.  While my 25x100s (with their 2.33-degree true field of view) is even more awe-inspiring and impressive, even though M31 extends beyond the field edges.
I have three different telescopes that can provide true fields of view of 2.6 degrees or wider -- with apertures ranging from 80mm (true field up to 4-degrees), to 130mm (true field up to 3.1 degrees) to 152mm (true field up to 2.6 degrees) -- all can provide some very nice views of M31-32-110 -- from a dark enough sky.
From a dark enough sky, the binocular (or telescope) hardly seems to matter.  On the other hand, if the sky is too bright, the view is likely to disappoint -- again, regardless of the binocular (or telescope).


Do not need to add much more. As SKETCHER already mentioned that a dark sky is a must to really see.

I have seen it from 1" instrument to 12" instrument but seeing in the darkest sky is completely different experience.

#31 Maljunulo



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Posted 21 December 2020 - 02:27 PM

If anyone mentioned Fujinon FMT-SX 10X70 iI missed it.


The best view I ever had was during the Great Northeast Blackout of the 1960s, using a not-very-good pair of 1950s 7X50. (Stellar, or some such?


It almost filled the field from one side to the other.

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#32 Rich V.

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Posted 21 December 2020 - 03:03 PM

If you're looking to see the entire galaxy framed inside the FOV, under dark skies the 4° FOV of a 16x70 frames things nicely.  My 3°  22x70s go deeper but the framing gets tight.  The darker the skies, the bigger M31 gets and the wider FOVs help.


A 100mm bino or BT shows more detail, of course, but going below 3°, you have to pan back and forth to see the whole galaxy.


Again, what's best is personal but I like having different options to choose from.



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#33 Peacock


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Posted 21 December 2020 - 06:53 PM

The best view I've had of the Andromeda Galaxy was with a 15x50 Canon Stabilized in northern Queensland (-17 latitude), where M31 rises to a reasonable altitude, much better than in Victoria, where I live.


I remember seeing M31 in rural northern Victoria at -35 latitude with 8x42 binoculars and the view was quite disappointing simply because of the extinction effect.

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#34 CAAD9



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Posted 29 December 2020 - 05:51 AM

This is a perennial question that I agonise over...


in my stable the choices generally fall to the following 3:

1) 10” dob (fl 1200) using 41mm Panoptic giving just over 2 degrees of tFov and comfortable stable views and decent aperture - but obviously 2 degrees leaves a lot of the galaxy behind.

2) Fuji fmt-sx 16x70 giving 4 degrees of tfov, captures the whole galaxy and m32 and 110, no real details on 31’s spiral arms and since I only have a so so photography tripod not always the most stable views nor very comfortable viewing.

3) canon 18x50IS giving 3.7 degrees of tfov, even less aperture such that companion galaxies don’t pop the way they do in Fuji’s and forget about any detail in spiral arms. Very comfortable to use.


All in all I think my favourite views are from the Fuji 16x70. In my observing that has been the best compromise between capturing the whole object and showing detail.


Having said all that, my favourite ever view of Andromeda was with a 20” dob (not mine) and 21mm Ethos EP. Only about 30 arc seconds fov (I think,I’m not really sure) but the detail in the spiral arms was deeply moving.  I could not drag my eye away from it.  Aperture fever anyone?

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#35 jprideaux


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Posted 30 December 2020 - 04:20 PM

If Andromeda is up and the sky clear and I'm planning on going outside, I always grab my Canon 10x42 IS binoculars.  I then find Cassiopeia and use the "larger triangle" as a pointer to where to look.  Then find the "smudge" and marvel that it is a whole galaxy outside the Milky-way. (and people only realized that about a 100 years ago)  I never seem to get tired of seeing it.


Yes, it is much better in a very dark sky.  It will also be brighter with larger binoculars.  If you go too big (in aperture), though, you can't fit all the distended parts in the field-of-view.  Although if your skies are not that good, you can't see those distended parts anyway.


Although I have some larger straight-through binoculars, I tend not to use them that much because of the neck-strain when looking at something a bit higher in the sky.

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