Binocular size confusion

[banjaxed]

A friend showed me a small pair of binoculars and the size on it the was 30 X 60, I know with most binocular sizes the first number is the eyepiece diameter and the second the objective lens. These binos fit in the palm of your hand so they are obviously nowhere near that size. Does anyone know what these numbers represent or is it just a Chinese anomaly ?

[johninderby]

 

That seems a bit strange as the standard meaning of the numbers is as below. Would like to see a photo of them. 

From a binocular website.

What do the Numbers mean?

Binoculars are often specified by a set of numbers such as 7×35 or 8×40, the first number indicates the strength of magnification(how many times closer the subject is to you, 5 times closer, 7 times closer, 10 times closer) and the second number is the size of the objective lens measured in millimeters going across the lens. The size of the objective lens will determine how much light the binocular can obtain for effective viewing. The higher the number, the larger the lens; in effect allowing more light to pass through thereby projecting a brighter image and viewing experience. However, binoculars with smaller lenses are more compact and portable.

[johninderby]

Ah sorted. The 30*60 is the model number. They are actually 30x21

https://www.amazon.co.uk/Binoculars-Powerful-Telescope-Lightweight-Astronomy/dp/B077BW5P5Y?th=1

Edited May 24, 2020 by johninderby

[banjaxed]

Apparently he bought them off Amazon https://www.amazon.co.uk/Binoculars-Collapsible-Fujunkang-Waterproof-Mountaineering/dp/B07VJDTB11/ref=sr_1_20?crid=2LTNNTT7SI627&dchild=1&keywords=binoculars&qid=1590334035&sprefix=binocular%2Caps%2C151&sr=8-20 but I still don't understand the logic.

[banjaxed]

Just now, johninderby said:

Ah sorted. The 30x60 is the model number. They are actually 15x22.

Thanks John, but how can you know what size they are by those numbers ?

[DaveL59]

as John says, it is usually mag x objective diameter in mm, but there does seem a tendency in some ads to add the 2 objectives so 2x30 gives 60 tho if they did that for the eyepiece/mag I've no idea how they've figured that one out, x15 each side? would give a very dark image I expect. Seems to be the way some cheaper ones have gone though just to wow buyers who've little knowledge on the equipment, bigger must be better after all...

[banjaxed]

1 minute ago, DaveL59 said:

as John says, it is usually mag x objective diameter in mm, but there does seem a tendency in some ads to add the 2 objectives so 2x30 gives 60 tho if they did that for the eyepiece/mag I've no idea how they've figured that one out, x15 each side? would give a very dark image I expect. Seems to be the way some cheaper ones have gone though just to wow buyers who've little knowledge on the equipment, bigger must be better after all...

Now that makes sense Dave, it seem my first assumption was right, Chinese anomaly 🙂

[johninderby]

Why they don’t use the standard way of descibing them who knows? 🤔🤔🤔

Just a very cheap and nasty  pair of bins I would assume. 🙀🙀🙀

Product Description

Specification:

Magnification: 30X

Objective Lens Diameter: 21mm

Line Field: 126m/1000m

Eyepiece Diameter: 24mm

View Field: 7.2째

Color: Black

Fold size: 9.2cm x 6.2cm x 3.7cm

Edited May 24, 2020 by johninderby

[banjaxed]

Maybe the moral is that if they don't know the size of the binos they are selling then keep well clear. Luckily I am not in the market for miniature binos 😀

Edited May 24, 2020 by banjaxed

[Peter Drew]

I think they must have been adding the eyepiece field of view together as well, I can't see 30x providing a field of 7.2 degrees as stated on the body.    🙂

[DaveL59]

2 minutes ago, banjaxed said:

Maybe the moral is that if they don't know the size of the binos they are selling then keep well clear. Luckily I am not in the market for miniature binos 😀

some even quite the lens area in sq-mm as the size, all a trick to con folk into believing they are mega-good when they are just cheap junk

[Peter Drew]

Just noticed that they are actually 15x but the question still remains.

[banjaxed]

2 minutes ago, Peter Drew said:

I think they must have been adding the eyepiece field of view together as well, I can't see 30x providing a field of 7.2 degrees as stated on the body.    🙂

Yes it is very confusing Peter but as I stated in my previous post I am not looking for miniature binos it was just my curiosity.

[johninderby]

Don’t think Leica are going to be worried about the competition.

[bomberbaz]

35 minutes ago, johninderby said:

Don’t think Leica are going to be worried about the competition.

Indeed, couldn't even see where you would be able to mount them!

[John]

According to the blurb in the description, these are "Professional Binoculars". I wonder what the amateur ones are like

 

[johninderby]

6 minutes ago, John said:

According to the blurb in the description, these are "Professional Binoculars". I wonder what the amateur ones are like

 

These perhaps. 😁

[PeterW]

I grabbed a screenshot of those 30x60 recently as a website thought I might be interested in them...:-) Obviously a case of specmanship... more number, more better! Would be a lot easier to carry than my actual  30x70, especially if they did give a 7.2degree field at 30x.... could see my own ears...!!

Love the advanced Amber coatings...

Peter

[bomberbaz]

On a slightly more serious note, these are truly shocking and shame on amazon for their continued selling of them. I did a review check and there is nothing more recent than Feb 2019 which is a scathing one star review. There are no four or five star reviews since early 2018.

Caveat Emptor springs to mind but nevertheless amazon really should have pulled the plug on these as they are a piece of junk for sure.

[johninderby]

If you want a pair of mimi bins these are actually rather good. Of course thet are a wee bit more expensive than the ones above. 😁

Edited May 25, 2020 by johninderby

[BinocularSky]

No idea how you get a 7.2 deg field at 15x magnification - that would give an apparent field of 108 deg. I wonder if they are citing the field in square degrees or the magnification in areas (superficial) instead of diameters (linear).