Here are some general notes on bino’s that may be of help.
Classification:
Bino’s are classified by the diameter of the (front) lens, called the “objective lens” and their magnification. So,
Magnification and diameter of lens:
7x50 gives x7 magnification with a 50mm diameter objective lens.
8x42 gives x 8 magnification with a 42mm diameter objective lens.
8x24 gives x 8 magnification with a 24mm diameter objective lens.
The 50mm bino will be able to “grab” or “gather” more light as it is bigger than the 42mm and 24mm bino.
x10 magnification can be difficult to hold steady as the image will appear to wobble unless we use a tripod or rest our elbows on a wall or table.
At the eyepiece end – where you look through:
The next important attribute is the “exit pupil”. This is the small circle of light you can see at the eyepiece when holding the bino’s up to the bright sky. Why is the exit pupil important? Well, our physical eyes have an iris that expands in the dark and shrinks in the light. In a healthy young person, the diameter of the iris when fully opened is approx 7mm. In a middle aged adult, it is only 4 or 5 mm due to the ageing process.
For 7x50 bino’s the exit pupil is 50/7 = 7mm (approx).
For 8x42 bino’s, the exit pupil is 42/8 = 5mm (approx).
For 8x24 bino’s the exit pupil is 24/8 = 3mm
Image brightness:
Therefore, the 7x50’s will produce a bright image that will match the aperture of your iris on a dark night.
The 8x42’s will only illuminate the central 5mm of your eye’s 7mm iris aperture.
The 8x24’s will only illuminate the central 3mm of your eye’s 7mm iris aperture.
Eye relief:
This is a measure of how close you will have to place your physical eye to the eyepiece to see a fully illuminated image. If you need glasses to correct your vision, then long eye relief is good. I understand that if glasses are simply for e.g. close up reading, then they need not be worn for looking through bino’s as they are not correcting for optical defects such as astigmatism?
Notes:
WARNING – never, ever look at the Sun through bino’s or any optical instrument – you will be blinded immediately.
Traditionally, 10x50's or 7x50’s are classified as good astronomy bino’s because of their light grasp (50mm) and exit pupil (5mm & 7mm respectively) but they can be heavy and difficult to hold still.
What will you use them for?
If you would like to use the bino’s for bird watching, then models from Leica will typically focus close, to around 3 metres. All round or general purpose bino’s tend to only focus down to maybe 5 to 10 metres.
Shops in Brisbane:
York Optical in Fortitude Valley.
Sirius Optics at Underwood.
Photo Continental at Mt Gravatt.
I’d better stop here as I’m uncertain at your level of understanding and fearful of swamping you with too much stuff.
"O", theres a guy called robert Bee who has written a book about observing with a small telescope or binos, i cant remember the title but if you are interested i can find out :0
Is there a general consensus on any good all around binocular?
One that "you can't go wrong with" ?
Well don't know about "general consensus, but I can confidently say that you cannot go wrong with an AOE 50mm HG binocular from www.aoe.com.au for hand held use. Only thing you need to decide is magnification, which is an individual thing: 10x if you can hold it steady enough, or 7x if the 10x gives too much of the shakes. I used to own the 7x50HG (then lost it ) and it is an exceptionally good binocular, as good as brand name units costing 2-3x as much. Of course you cannot go wrong with much more expensive binos from the reputable companies, e.g., Pentax, Nikon, Fujinon.
Tripod mounted binos are a pain to use any more than 40 degrees above the horizon, unless the tripod is designed/modified for binocular astronomy.
I guess the most common size binoculars used would be 7x50's. They are very common and made by many manufacturers. The price and quality will vary tremendously though. If you get cheapies, they will have all sorts of defects - astigmatism, reflections, coma etc - which will make it almost impossible to focus stars into a nice clean dot! They may however, give quite reasonable "terrestrial views". So if you try some out, don't just expect to get good star images from the ones that give a good view of a bulding across the road. The best time to try them out would be if you could shop in the evening after the sun goes down, and walk outside with them.
Alternatively, you could spend a lot of money, and it is not difficult to spend a couple of grand on a pair of binoculars, even 7x50's, you will get excellent optics, but you could have bought a cheaper pair and a pretty nifty telescope. I guess it comes down to how much you want to spend and taking into account the details given in previous replies.
I have a pair of Saxon 11x80s which are OK, they don't give perfect images but they do the job, but even they cost me a couple of hundred last year. The 11x magnification is about the limit for handheld, 7x is pretty easy to hold steady and light enough to hold up for a while.
Like telescopes, steer clear of "department store" binoculars, better to spend money on a reasonable pair than some cheapies that you will come to hate! The major scope manufactures make reasonable binos, like Meade, Celestron in the mid price range. Saxon, Orion etc are cheaper and probably lower quality. If you have lots of money, you could look at manufacturers that are known for their optics, Pentax, Zeiss, Leica etc but then you are looking at lots of money. I would try to not buy a brand that doesn't make other types of "optical" equipment...this will keep you away from most of the cheap and nasty ones.
I've got two pair - both actually from Andrews Communications in Sydney - 10*50 Waterproof (don't know just how waterproof??) and the 20*80 triplets. Both are very reasonably priced, and surprisingly good quality for the price too. I'd go for a pair of 7 or 10 by 50's if I were you - you can easily take them to the football also then!
You really will need a mount for 70-80mm binos.......
Denis, very detailed explannation! Will try to head to
York's at lunch time today. Might have a chance to
meet up with u one day since u r in BNE. R u with a local
society? Which is most active society here?
plasmodium, will have a look at those too.
OneOfOne, I'll stay away from the cheapies and department store ones.
janoskiss, those binos look real good... will definitely consider them eventhough i am not much of mail order person and prefer to go to the shops ... guess i will have to change soon with everyone else getting good range and deals by mail order!
I think that would package up well into a "how to" for bino-buying! You can even collaborate with others (if you want) and gather other information from this thread (and other bino threads).
What do you reckon? Maybe while the paint is drying under the eaves?
I find that there are many "how to" guides but after reading a few, the scope is still too big. I feel that a few beginner like myself need more specific advice, hence the "consensus" sort of things. Something of this line:
1. Good all around binos at reasonal price ( $100- $300 )
Brand x,y,z, model such and such .. all are accepted as OK ... choose one!
The choice then is individual but at lease these are not lemons.
2. If you are on budget ( under $100)
Brand and model such and such is recommended.
3. If you want to spend more ....
BTW, is Celestron a "department store" brand? I see them at Dick Smith and Aust. Geographic but also at reputable optical stores.
Denis, very detailed explannation! Will try to head to
York's at lunch time today. Might have a chance to
meet up with u one day since u r in BNE. R u with a local
society? Which is most active society here?
"O"
Hello O
The standard recommendation is "don't buy before you try".
That is, meet up with a local club (I am a member of the Brisbane Astronomical Society) and have a look through a selection of bino's and weight up the pros and cons in the field. You will then have a clearer set of personal requirements that you can use to select the best bino for you.
I believe York Brisbane is no more.
I know what you mean about mail order vs walk-in shop, but in practice what's on offer in local shops is very limited unless perhaps one happens to live in Sydney.
AOE are excellent to deal with. Their customer service, both pre and after sales is second to none. I bought quite a few things from them in the past and they've never let me down. Their advice is always spot on too.
I just 'phoned York Optical in Brisbane and spoke with Gregg so they are very much open and in business. I mentioned your interest in binoculars and Gregg said mention that "Dennis from the BAS" recommended York as a potential supplier and they would be able to give you a discount.
I purchased my Celestron C9.25 from there so it seems they remember me. I understand that they stock Fujinon (premium quality) and Celestron binoculars, but be sure to check other brands too, in particular Photo Continental at Mount Gravatt have a range of Pentax, Nikon, Zeiss and Leica amongst others, and I have always found them to be knowledgeable and helpful too.
I think that would package up well into a "how to" for bino-buying! You can even collaborate with others (if you want) and gather other information from this thread (and other bino threads).
What do you reckon? Maybe while the paint is drying under the eaves?
Okay Mike, I'll give it a go. I'll write the general vanilla stuff and then circulate the article to others who would like to collaborate on this project, for contributions and peer review.
After much looking around for my first binocular, taking all things as quality, value for money, local availability, and a newbie's needs in mind, here is my conclusion:
Pentax 10x50 PCF WP
I am not saying this is the best binocular you can get but would I be wrong to say that this would be one of those binocular "a newbie can't go wrong with" ?
The listed price at photocontinental is $299. ? OK
I wouldn't mind spending more if there are clear and significant differences in quality in the more expensive models. I am also keeping in mind that extra money can be put toward a very good quality/higher power mounted binocular later on.
Pentax is a nice choice. Just make sure it's not an older model (they tried to do that to me in a camera shop once with a Pentax 12x50, i.e., sell me an out-of-production model without telling me).
btw. the only thing I don't like about that Pentax is the 50 degree FOV. For a 7x50 that would be okay, but for 10x50 I'd want at least 60 degrees, even if the outer 10 degrees is not as sharp as the centre. A 5 degree true field is fairly small and makes star hopping more difficult.
) and it is an exceptionally good binocular, as good as brand name units costing 2-3x as much. Of course you cannot go wrong with much more expensive binos from the reputable companies, e.g., Pentax, Nikon, Fujinon.
