Large binos - are they worth the cost?

[Etoille]

I was thinking about getting some large binos, but was wondering how much detail can you see at 20x magnification and whether it is worth the cost? For example can you see details on planets or their moons? Can you split doubles? I notice also that some of the more expensive ones have interchangeable eyepieces and can go up to 40x but cost substantially more. Again, is the cost worthwhile?

Obviously one can get a cheap pair of 20x50s on a market stall, but I guess these don't really cut it?

[ollypenrice]

I wouldn't use binos for planetary observing or splitting doubles, not unless they were the big ones with interchangeable lenses. The strength of binos lies in widefield observing. At high powers their complex light path through prisms has to compromise their resolution. I have some basic 15x70s and like them, but they struggle to show a clean disc on Jupiter, let alone detail. Nice view of the moon, though.

By the way, Etoille, I live in Etoile!!

Olly

[Etoille]

I wouldn't use binos for planetary observing or splitting doubles, not unless they were the big ones with interchangeable lenses. The strength of binos lies in widefield observing. At high powers their complex light path through prisms has to compromise their resolution. I have some basic 15x70s and like them, but they struggle to show a clean disc on Jupiter, let alone detail. Nice view of the moon, though.

By the way, Etoille, I live in Etoile!!

Olly

This is what I was concerned about. I have a pair of 11x70 and no matter how well you focus them you always get some astigmatism on planets and you can't really tell whether that's the rings around Staturn or an optical distortion. The thing is these are supposed to be pretty decent quality. The 8x42's I have for general use are much better but magnification too poor and even at £250 still distort brighter stars. Both instruments still give some decent views of the sky though, especially large open clusters etc.

I just thought something bigger might do a half decent job of showing planets like Saturn and Jupiter and their moons or the phases of Venus and maybe even the Orion nebula. I'm not expecting a telescope view of course, but I would settle for a reasonably clean view without distortion of the planetary disc so that you could tell what it is rather than just seeing a distorted blob of light would be nice. As you say though, perhaps with the complication of superimposing two already complex optical paths makes this impossible at a reasonable price.

PS, I didn't know there was a place called Etoille. Used to live in Paris for a while though.

[newman]

One of the things to consider is ergonomics. 20x80 or 25x100 are very large, heavy, and unusable from hand. You'll need a sturdy photo tripod or a bino mount. Problem with that is, most binos are for straight-through looking; this causes me neck pains when looking up. With my refractor, I have a 90 degree diagonal which makes observing much more comfortable; but I've found large bino observing to be, quite literally, a pain in the neck. Try before you buy if at all possible.

[Etoille]

One of the things to consider is ergonomics. 20x80 or 25x100 are very large, heavy, and unusable from hand. You'll need a sturdy photo tripod or a bino mount.

Its a good point and yes I had considered that a mount will be neccessary. I already have a sturdy photo mount I could use so long as it would support the weight.

Problem with that is, most binos are for straight-through looking; this causes me neck pains when looking up. With my refractor, I have a 90 degree diagonal which makes observing much more comfortable; but I've found large bino observing to be, quite literally, a pain in the neck. Try before you buy if at all possible.

Again another good point. Most of those on the budget end are straight. Helios Quantum 5 are 45deg but pricey. I have seen these mounts that look a bit like the arm on a large desk mounted lamp but I can't seem to find anywhere that sells them in the UK.

[nckjsmitj]

One of the things to consider is ergonomics. 20x80 or 25x100 are very large, heavy, and unusable from hand. You'll need a sturdy photo tripod or a bino mount. Problem with that is, most binos are for straight-through looking; this causes me neck pains when looking up. With my refractor, I have a 90 degree diagonal which makes observing much more comfortable; but I've found large bino observing to be, quite literally, a pain in the neck. Try before you buy if at all possible.

I've seen a few large bins with the oculars set at either 45' or 90' to counteract the pain in the neck issue. But you'll need to raid the piggy bank, and probably the piggy banks of of several other family members to afford them.

N.

[Mr Q]

Another issue to address is the exit pupil size of larger (objectives) - young eyes can dilate to the size of these large aperatures (6-8mm) but as we age, our capacity lessens. At age 64, my eyes can't dilate beyond 5 or 6mm even after an hour of dark adaption so the light gathering power of say, 15x125 is wasted for me but maybe not for a 20 year old.

[Moonshane]

I cannot see the point. If I were considering something like this, I'd go for a refractor and a pair of binoviewers. Probably cheaper, better and more flexible. That said, I was even unsatisfied with a 90mm f5.5 refractor I bought so bought another 6" newt which gives far superior views.

I don't get on with binoculars for astronomy, no matter how big or small. not enough power for planets and more hassle than a scope (for me anyway).

[BinocularSky]

Just a few points:

* I love binoculars for astronomy. Anything up to about 15x70 is essentially grab-and-go (even if monopod-mounted). My big binocular takes all of 10 minutes to set up on its parallelogram, and is excellent for the larger DSOs. Very convenient and easy to use.

* Binoculars for planets? Wrong instrument!

* Eye-pupil dilation: very much an individual thing. Mine (age 62) are a bit over 6mm, but I've known 40-yr olds who only get 5mm. However, I find that an exit pupil of around 3mm is generally right for me in the light-polluted skies of southern England (bigger than that, and my astigmatism becomes obtrusive).

[Etoille]

Some very interesting comments here.

I've never really found exit pupil to be much of an issue on a scope except a high powers where eyepieces of 4mm and below become a real pain. However with my current binnoculars I did keep this in mind which is why I purchased a pair of 11x70's which give an exit pupil of 6.36mm, deliberately sacrificing a bit of magnification for the greater exit pupil against a pair of 15x70's. Unfortunately I'm now stuggling to hold these for more than 5mins which I why I was thinking about something mounted which then led to me thinking that I might as well go bigger.

But then there appear to be other considerations. For example, I was considering a 20x90 rather than 25x100 (exit pupil 4.5 versus 4) but for that particular model is fixed at x20 mag. A much more expensive model is 20x100 (exit pupil 5.mm) but also comes with a second pair of eyepieces at 40x which would give an exit pupil of only 2.5mm. Is there any point to push to this magnification? Another option I'm considering is a pair of 20x110 giving an exit pupil of 5.25mm. These are considerably more expensive than the first option, but less expensive than the second, and again fixed at 20x. I am probably tending towards these latter ones but am still wondering whether its worth the cost and whether I should be content with what I already have.

tetenterre, I note your comment that binos are the wrong instrument for plannets. There is no question that a decent frac is far superior here and my wife already has one of those... I also note your point about the monopod. Maybe that's a better way to go for grab and go purposes then getting a bigger instrument which would probably need a tripod or parallel mount. Are 20x110 (7.1kg weight) too heavy for a strudy (heavy duty pro photo) monopod?

[BinocularSky]

Are 20x110 (7.1kg weight) too heavy for a strudy (heavy duty pro photo) monopod?

Never tried it, so I don't know for sure, but I imagine it would feel very unstable because usually the monopod will not be perfectly vertical.

[Etoille]

Have seen a nice pair of Helios Apollo 15x85's on Uk Astro. I'm tempted as they fall within my price range but wondered how much difference would there really be between a 11x70 and 15x85 (other than the weight)?

[Ags]

I've thought about big bins, but I think my ST80 at 16x magnification gives the same widefield view...

[Phil Fargaze]

I once had my 20x100 bins pointed at a comet alongside an 8" dob and I decided that the bins had the best view. They really do perform well with faint large field objects. Plus they are great for taking on holiday.

[Etoille]

I cannot see the point. If I were considering something like this, I'd go for a refractor and a pair of binoviewers. Probably cheaper, better and more flexible.

Well, my wife already has the Evostar 120 but a binoviewer with two eyepieces would set me back at least £250 which is going on for the price of a pair of binnoculars. Still it might be worth considering.

I've thought about big bins, but I think my ST80 at 16x magnification gives the same widefield view...

Yes, I could also get the ST102 or the ST120 or even one of the Acuters which would double up as a terrestrial instrument, or for a bit more the Celestron C5.

You have both given me food for thought.

[Etoille]

I once had my 20x100 bins pointed at a comet alongside an 8" dob and I decided that the bins had the best view. They really do perform well with faint large field objects. Plus they are great for taking on holiday.

Would that still have been the case in a 15x85 pair of bins?

[Ags]

I wouldn't go for the C5 or even the ST120. The C5 has such a long focal length it cannot get anywhere near the widefield view of bins, while the ST120 is starting to get a bit big in my opinion (but smaller I suppose than the evo 120 you are familiar with).

[Phil Fargaze]

It`s hard to say if the 15x85 bins would have managed a better view than the dob, probably not but it kind of gives you an idea. I checked the details of my observation and it was comet Lulin back in March 2009. There was a nearly three quarter moon nearby and I was in a light polluted London suburb with transarency med/poor. All that considered, it was a fairly severe test and the comet was on the border of detection.

[Etoille]

It`s hard to say if the 15x85 bins would have managed a better view than the dob, probably not but it kind of gives you an idea. I checked the details of my observation and it was comet Lulin back in March 2009. There was a nearly three quarter moon nearby and I was in a light polluted London suburb with transarency med/poor. All that considered, it was a fairly severe test and the comet was on the border of detection.

Phil, thanks for checking and your feedback. I had wondered which comet it was. Your comment made me think about Holmes p8 which I 'discovered' while out with my wife scanning the sky with 11x70 bins. Having confirmed what the bright object was, I took a closer look with a Meade LX90 scope that I had at the time, yet, set against the background, it somehow looked better (and brighter) in the 11x70 bins!

I decided then that that the bins were a worthwhile purchase. Haven't seen anything as exciting since then, but I still enjoy scanning the Milky Way with them every now and then as well as observing other larger objects.

This actually makes me think about practicalities, since to view Homes at the time, I remember having to look almost straight up at the Zenith which I presume could be a problem with larger bins?

[pel]

These ones look very cool -

http://www.vixenoptics.co.uk/Pages/astro_binos.html

[Etoille]

These ones look very cool -

http://www.vixenoptics.co.uk/Pages/astro_binos.html

Yes, indeed, but currenly too far beyond my budget...

I am looking at these however:

http://www.astrobuysell.com/uk/propview.php?view=56197

As good a price as that is, I note I can also get Celeston's from Amazon at half that price - but then they are also half as light. They seem to get good reviews, but presumably not in the same league as the Helios?

[Grunthos]

I used to own a Celestron but then bit the bullet and bought a Helios from ABS (marketed as Garrett).

I ended up gaving my Celestron to a friends kid. A week or so ago I borrowed it back to do a comparison with the Helios/Garrett I now have.

Tbh the Helios puts the Celestron to flight. Can't believe I used it for so long.

Am totally converted (or is that spoiled?). I'll never go back

[BinocularSky]

Am totally converted (or is that spoiled?).

I call it "cured":D

Seriously, it is impressive how these budget binocs can bring otherwise-undreamed-of stuff available to us; but once you have experienced what it could be like, you are spoiled.

[Phil Fargaze]

With the big bins you will have have them on a tripod, so objects near the zenith are kind of out of reach. What I tend to do is have the tripod extended as high as possible but even then a little bit of `yoga` is required.

[BinocularSky]

With the big bins you will have have them on a tripod, so objects near the zenith are kind of out of reach.

... unless you use a parallelogram

(On the batphone, so probably riddled with weird predicted text.)