Decide on three compact binoculars (1 Viewer)

Hello,
Thanks for all opinions!!
I had using a 18X50 IS Canon, good for astro but for birding this unit very poor in resolution, image very "inquiet"..I have a 12X36 very very best that the big Canon IS. I like know if the image in the small 8X25 is tembling o more stable, like the 10X30 model..
Thank you very much

wachi

I prefer the Canon 10x30 IS the best also.

First: very much differences between the 8X25 to 10X30 in relation optics quality and smalll size?
Second: very much differences between the 8X25 to 8X30 or 8X32 in relation above questions?
third: very much differences between a 8X25 to 10X25 in relaton vibration images? 8X vs. 10X ? and poor light for the 10X ?
Thanks again for this questions.
Wachi

wachipilotes said:

First: very much differences between the 8X25 to 10X30 in relation optics quality and smalll size?
Second: very much differences between the 8X25 to 8X30 or 8X32 in relation above questions?
third: very much differences between a 8X25 to 10X25 in relaton vibration images? 8X vs. 10X ? and poor light for the 10X ?
Thanks again for this questions.
Wachi

Click to expand...

Hombre, ¡Tantas preguntas a la misma vez! ¿Y cómo empezar? Okay, I think the optics of the 8x25IS are better, but the 10x30IS is better overall because the IS system therein is less 'jerky'. I'm not quite sure I understand the second and third questions, as Canon don't make IS binos in 8x30, 8x32 or 10x25 formats.

Some Optics Education

wachipilotes said:

First: very much differences between the 8X25 to 10X30 in relation optics quality and smalll size?
Second: very much differences between the 8X25 to 8X30 or 8X32 in relation above questions?
third: very much differences between a 8X25 to 10X25 in relaton vibration images? 8X vs. 10X ? and poor light for the 10X ?
Thanks again for this questions.
Wachi

Click to expand...

Hi Wachi:

The combination of magnification [the '8' in the 8x25] and objective/aperture [the '25" in the 8x25] is the "rating" (often misnamed power). When the objective gets larger, the binoculars generally get bigger and heavier. But this "rule" can vary if the bins are built with a polycarbonate body or a magnesium body or have different amounts of glass in them.

But brightness generally decreases when the objective gets smaller or the magnification increases. At the same aperture size (25mm, 32mm, etc.), as you increase magnification the image becomes less bright, and this is more obvious at dawn and dusk. Thus, a 10x32 binocular, technically having more “power” than an 8x32, will be less bright under low light conditions. More power isn’t always a good thing! So, (all other things being equal) a 25 is smaller, gathers less light than a 30 which gathers somewhat less light than a 32 mm.

The higher the magnification (10 vs. an 8) will introduce more shake to an image (unless you have an IS to compensate). Some people can handle a 10X pretty well without IS but some may prefer the relative steadiness of an 8X (as well as a brighter image).

When you are looking at the combinations above, there is a shaft of light called the "Exit Pupil" (EP) which is the actual amount of light hitting your eye.

This diameter of the EP (expressed in millimeters) exits a binocular’s eyepiece and enters through your pupil. The EP is calculated by dividing a binocular’s aperture by its magnification, e.g. 42mm / 8x (for an 8x42 binocular) = 5.25mm.

This is one of the primary reasons most birders choose an 8x42; it’s the best combination of magnification and aperture, keeps the binocular’s physical size from being unwieldy, and still delivers a bright image at moderate power.

Here are EPs for some binocular ratings:
8x25: 3 EP
8x32: 4mm EP
8x42: 5.25mm EP
10x21: 2mm EP
10x32: 3mm EP
10x40: 4mm EP
12x36: 3mm EP

Just remember that your age will determine the Max EP that you can use.
A very young person have an maximum eye pupil of 8mm.
After 30 years old it will be smaller than 7mm.
After that about:
40 years old: 6mm
50 years old: 5mm
65 years old: 4mm
And finally to the very end of life about 3mm.

So just keep these "few" things in mind when buying a pair.

For me, I have recently gotten a pair of 8x25s, not to replace my full size binos, but to provide a more packable, decent quality pair that will fit easily in my backpack and will not weigh me down. I have a pair of HD 8x32s which for me are the best all around combination of size, weight, and performance since I do little birding at dawn and no birding at dusk.

I'll let the others on this forum argue the merits of quality and small size (IMHO, you can get very decent small bins for not that much money but you also can give up durability and build quality for less money), but I thought I'd give you some basics. Hope this helps!

Glenn

Glenn:

You have made a very nice presentation of the sizes of binoculars and how important the size
of the exit pupil is.

For general binocular use a 4mm exit pupil is a size that makes viewing very enjoyable.
Most binoculars fit into this size or larger, and for a very good reason.

Jerry

thanks all for your advices, complicated for me this theme, but ! muchas preguntas,verdad Sancho?
I imagine that 8X32 is best overall that 8X42 ? 4mm pupil....
Wachi

NDhunter said:

Glenn:

You have made a very nice presentation of the sizes of binoculars and how important the size
of the exit pupil is.

For general binocular use a 4mm exit pupil is a size that makes viewing very enjoyable.
Most binoculars fit into this size or larger, and for a very good reason.

Jerry

Click to expand...

Thank you Jerry!

Hello again,
The truth is that I think I'll choose a 8X25 model.
I have come to think 8X32, or some similar model as a granite ED Celestron 7X33, perhaps manageable and optically good exists, by what they are smaller and lighter than the 8x42 or similar models.
But ...... and this is a big "but"
the use I would give would be to carry in my pocket when I go out for a walk to the countryside to see landscapes, when I go cycling in the rural walk, and when I run, for this reason I seek some binocular lightweight and great campo.Además usually go places where large areas are no trees, no forests are like steppes, very distant horizons, and raptors are usually enough, the question I have now is:
Better, the model 8X25 vs. 10X25 model?
My question: - vibrates much the image on the 10X,? Best amplitude image in the 8X model?
In these models, 8x25 and 10x25, you could recommend me some models with best value?
As always, I thank you in advance for your opinions and advice.
Wachi

I would suggest you also have a look at:
-Vanquish 8x26 --- reverse porro at about 125$
-Viper 8x28---roof prism at about 300$
or, why not,
-ZRS 8x42---a monocular, about 135$ and weighing only some 10oz

I have a similar need. My lightweight hiking bins are a reverse porro, a 7x24 (compact and less than 300g). This lives in my back-pack for days when I have no expectation of birding. Although a 7/8 x 25 may give good performance, they can be fussy to fit onto the face and restrict eye movement when viewing.
For outings where I do expect to need my bins, but don't want to carry my "full size" bins, I have been looking for a light-weight 8x32 (actually, I wanted a 7x32/30 roof <400g, but these are rare) and found only a few <400g.
For a while, the Opticron Discovery 8x32 at around 380g and £160 looked to be my best option. My wife had one, so we know it would work well.
The new hot favourite for my use would probably be the Nikon M7 8x30 (430g). At around £260 in the UK, it's more expensive than I wanted, but I suspect that even if I bought something cheaper, I may well end up buying one of these later.

Good luck in your choice.

I know all your models are 8x, but I wouldn't buy a pair of compacts until you look at the Bushnell Ultra HD 10x25's. They are nothing short of remarkable. I so wish they made them in 8x, but the 10x are superb.

"
Although a 7/8 x 25 may give good performance, they can be fussy to fit onto the face and restrict eye movement when viewing.
"

One notable exception is the Bushnell Elite 7x26. They play a little trick internally to give you
a bigger expanse for eye placement. The M24 design (7x28) is a bit rare, but it gives you the
nice 4mm exit pupil of the 8x32 with a lot less less size.

There are many old 6x30s with zero 'blackouts', generous eye placement, haze-cutting,
and good with glasses (just unscrew the eyecups). I pack those often for a hike.
The 6x30 Yosemites are great but eye placement is fussy, esp. without glasses.
I use binoculars both with and without glasses.

The Kowa are nice though I have not tried the others you mention. The nice thing about the Kowa is the focus wheel too, and it has a single hinge which makes looking through them easier when aligning to your eyes. Most compacts are dual hinge and a pain to align to your eye sockets if you want to look at something quick. I would stay away from any dual hinge model of compacts.

Very much differences between a 8X25 model and 8X32 model binoculars, in size, weight, and views ?
Thanks
Al.

Al,

Here is a size comparison of my Swarovski 8x30 CL with my Swarovski 8x25 CLP.

http://www.birdforum.net/showpost.php?p=2880825&postcount=31

Bob