Why 8x magnification may not be such a good compromise as it first seems (1 Viewer)

Part I

First of all, let me admit these are my own personal thoughts and as such they are biased.
I will argue that a set of two binoculars for different birding situations will cover all you'll need.
The reader will immediately realise that I'm talking about a higher power and a lower power binocular. If you're firmly decided to always bring only one binocular, my solution will challenge your idea. Will you be a convert or will you oppose?

The idea of owning and using one single binocular for all and every situation is admittedly appealing. The beauty of simplicity is a factor that shouldn't be neglected.
A birder that uses one configuration and sample will become one with his/hers device. Using it will form habits that live deep in the brain stem. You will know exactly how much effort to put in the act of lifting it, putting it in front of your eyes and turning it towards whatever you're looking at.
You will also know exactly how many degrees you will have to turn the focusing knob to achieve sharp focus instantly. After repeated use you can overcome some of the flaws that your binocular has, especially if you have chosen a very good model with high performance in most, if not all, regards.

Even the environmental aspect can be considered, and whether it really is fair that we own vast collections of optics while birders in development countries may be happy to own one set, regardless of quality and configuration.

However, these are objections that mostly will come from non-optic geeks. Few of us seem to settle down and decide that we own the world's best binoculars, discussion ended, period.
There is no such thing as the best binocular, and if such animal exists, its hegemony is short-lived thanks to the ongoing development and refinement that the sport optics manufacturers serve us with.

Like I wrote, I will argue that a set of two will perform better than one single binocular. This is nothing remarkable, everywhere around us people have sets of golf clubs, shoes, cars and bikes, whatever.
Let's take the car as an example. Depending on the individual needs, a compact sedan or 4 WD SUV may fit the bill, or perhaps a truck. None is perfect for all situations, it can only be ideal for a limited range of situations. If you badly need a pick-up with great capability to move around goods, you may need another car to transport your family. And there will be situations when you just can't go further, or don't want to make noise, then you should complement the pick-up with a bike.

OK, time for some optics, or should I call it philosophy?

Part II

We know that a low powered binocular has a greater depth of field, faster focus and (usually) wider field of view. At short distance it can give amazingly vivid 3D experience and it is indispensable for chasing warblers. It provides large exit pupils making it even more suitable for use under foliage even when light fades. It also withstands the effect of shaky hands very well.
The only area where it falls short is reach. At really long distance, a 6x or 7x may be insufficient for showing the detail needed for that ID you really want to make. But the decrease of the shake does indeed also decrease that gap between higher and lower magnification binoculars.

To obtain the missing reach, you may need high (10x) magnification. But all the virtues of the lower power sibling will be gone with the wind once you change.
Most of all, shake will increase proportionally with the magnification. The movements of the image will reach 54% longer with a 10x compared to a 6.5x.
Many people can't or won't handle a 10x properly and may need to settle with an 8x.
The increase of hand shake is present even when you're birding in the forest, so maybe you're best served by a 5x binocular for that task.

Assuming you're not having pronounced problems with hand shake, what will a medium powered binocular provide? In brief, I'm saying it's a quite mediocre compromise.
It will lack the ease and speed of use of a 6x or 7x . Its depth of field is clearly shallower, so you must adjust the focus more often. You may also notice that you must concentrate a wee bit more to avoid shake.

What about the reach? Well, magnification X at a certain distance resembles viewing the target at 1/X of the distance. If the bird you look at is 20 meters away, the magnification of an 8x makes it look like it's 2.5 meters away. If you're using a 7x, it looks like it is 2.86 meters away, and if it's a 6x it looks like it's 3.33 meters away.

But if you walk 2½ meters forward, the image of the bird through a 7x will have the same size as it had with the 8x at 20 meters. To achieve the same result with a 6x, you go another 2½ meters forward to 15 meters.
At shorter distance, the adjustment of position needed becomes proportionally less.
The longer the distance, the more you need to run forward to achieve that same image size you had with the medium mag binocular. Thus, at longer distance higher magnification pays off a lot more than it does at short distance.

Part III

Imagine three zones of distance – close, from 2 to 20 meters, medium, from 20 to 80 meters, and far, from 80 to 200 meters. Numbers can be questioned, but are of less importance, IMHO.

The 6x to 7x will be decidedly best at short distance, considering all aforementioned virtues and the fact that changing position has such good effect on image size at these distances.
It also does very well in the medium range, but where also the 25% greater magnification advantage EDIT: of an 8x vs a 6.5x will be somewhat diminished by hand shake.

The 8x to 8.5x will be very fine for medium distance but proves inferior for speedy close-range warblering due to its narrower FOV, slower focus and shallower DOF.
At long distance it will be fine too, approaching the limit of hand-holdability. Still, if you're birding over really long distance like shores or between mountain tops, you will experience a gap where you'd be forced to make use of a spotting scope.

The 10x is nearly impossible to use at the shortest distances (2-6 meters) and will behave somewhat flimsy up to 20 meters, where its magnification corresponds to a viewing distance of 2 meters.
Beyond that distance, into the medium range it begins to show its capability.
Provided that you can hold a 10x still, the extra magnification is useful from 20 meters and beyond, just where it's increasingly more difficult to use change of position to achieve a larger image.

So, what I'm arguing here is that an 8x is an inferior compromise since
1) its short range performance lacks
2) AND that a 10x provides more reach without the need to perform excessive changes of position.

The lower power binocular and the higher both handle the medium range just fine, but the medium power binocular falls short at both ends.

//L

One should really carry at least two pair with them at all times. Even when going to the bathroom.

Personally I did perfectly fine with one set of 7x compacts for almost thirty years. I have a lot of fun buying and researching and owning many pair now but cannot say my overall experience is better. Just different.

black crow said:

One should really carry at least two pair with them at all times. Even when going to the bathroom.

Click to expand...

:-O

Today I was birding between 9 am and noon, when I went to town. Just when I was at the ATM I heard a lot of noise above me. It was a lot of Herring Gulls shouting on a White-tailed Sea-eagle, who flew over the market-place and the church. I had my tiny Nikon Mikrons...need I say more? :t:

//L

Edit: At that moment, they were the world's best binoculars. And they are Nikons!

A 7+12x32 Leupold Switch Power turned out to be perhaps as the most used binocular in the field I currently own. The 7x32 configuration is convenient with ample eye relief to work even with fit-over sunglasses. 12x32 sounds like too much shake, doesn't it? But in practice I was able to get used to it. I found the restricted FOV as its most relevant disadvantage. But as most users of optics know, every configuration has its own disadvantages or trade-offs. I think it's time to rethink about binoculars with zoom or variable magnification.

Steve

I've wondered about those Lepold 7x +12x but never seen a pair. It sounds like the perfect combination for me, apart from one aspect. I'd need to add about 20oz to hold the 12x steady. Maybe lead loaded gloves would work?

I really like my 7x pairs, but I don't find a 10x a worthwhile difference.

David

...or just an 8/7x and a scope.

looksharp65 said:

The 8x to 8.5x will be very fine for medium distance but proves inferior for speedy close-range warblering due to its narrower FOV, slower focus and shallower DOF.

Click to expand...

I think you're overstating the limitations of 8 or 8.5x at close distances. Good models have FOV comparable to 7x models and have no issues with "slower focus." Personally, I don't see much practical difference between 7x and 8.5x . For me, 10x does seem compromised by FOV and DOF for most birding (i.e. at close and mid range in structurally complex settings), yet its magnification advantage at distance is quite modest so I'd be pulling out a scope anyway (very few distant birds are comfortably identifiable at 10x that can't be IDed at 8.5x).

I do think every birder needs multiple bins: an 8x20 pocket roof, 8x32 roof and an 8.5x42.

--AP

Carrying a heavy 12x is bad enough, a scope and tripod as well is a step too far.

David

LS:

I like your efforts on explaining what size binocular is the best choice. After reading all
of it, I think you have explained it very well in Part III.

The 8X or 8.5X is the best all-around, and as far as the qualities of your individual choice, that is up to you, or the users pocketbook.

I am thinking the 8x42 size is and will continue to be the most popular choice in the marketplace.

Jerry

looksharp65 said:

:-O

Today I was birding between 9 am and noon, when I went to town. Just when I was at the ATM I heard a lot of noise above me. It was a lot of Herring Gulls shouting on a White-tailed Sea-eagle, who flew over the market-place and the church. I had my tiny Nikon Mikrons...need I say more? :t:

//L

Edit: At that moment, they were the world's best binoculars. And they are Nikons!

Click to expand...

I actually feel naked if I leave the house without a pair.

My current favorites in power is the 7x and 9x. If I could only have one it would be the 7x. 9x is really my limit for holding steady.

It may be that the answer will eventually be something derived from the Sony DEV electronic viewers.
As far as I can tell, these glasses offer a very good zoom capability, so they can offer a wide field of view at low power and also substantial magnification.
Obviously bulk and image quality are still impediments, but these are known issues that are getting ample engineering resources.

NDhunter said:

LS:

I like your efforts on explaining what size binocular is the best choice. After reading all
of it, I think you have explained it very well in Part III.

The 8X or 8.5X is the best all-around, and as far as the qualities of your individual choice, that is up to you, or the users pocketbook.

I am thinking the 8x42 size is and will continue to be the most popular choice in the marketplace.

Jerry

Click to expand...

8X is still the best magnification and 8x32 is still the best all-around birding binocular.

Just a personal breakdown by magnification vs usage as best I can recall over the last 12 months:
6x 4%
7x 70%
8x <1%
9x 4%
10x 2%
12x 20%

Everyone's different.

David

Everyone should know Swift settled this question decades ago with the OPITMIZED Audubon 8.5x44mm, supposedly based on optical factors taking into account typical observation distances of ~30m or more as determined by the comfort zone of wild birds not habitualized to humans. But as with everything optical, "optimize" is just another word that means "compromise." And a compromise is never the perfect solution, rather the only solution that works for most people most of the time.

RJM said:

Everyone should know Swift settled this question decades ago with the OPITMIZED Audubon 8.5x44mm, supposedly based on optical factors taking into account typical observation distances of ~30m or more as determined by the comfort zone of wild birds not habitualized to humans. But as with everything optical, "optimize" is just another word that means "compromise." And a compromise is never the perfect solution, rather the only solution that works for most people most of the time.

Click to expand...

Just not a 'compromise' that is much use to me.

David

"One should really carry at least two pair with them at all times. Even when going to the bathroom. "
haha

LS, you are spot on about not finding the 'perfect' everyday situation pair. It's exactly like handbags for me. I've been searching years for that one perfect brand and style with the perfect amount of pockets, perfect size, look, feel, etc. It's a futile task.
I've realized just recently that binoculars are similar...I probably will never find the perfect bino to replace all binos. With that said, I highly prefer the 7x42 size which I recently purchased. I was birding for a few years with 6x30 and 8x32 and come to realize that 7x42 is best for me. It's all subjective though. I feel that 8x is a little too shaky for me since my shoulders hurt if I hold the binos up for too long and then my arms/hands cause too much shaking. I also prefer the wider fov in the 7x.

If I ever need serious magnification I will just get a spotting scope instead of buying a large binocular that will cause a lot of shaking.

It's true that we feel naked if there isn't a pair close by. I have crummy quality Bushnell 8x in the car (for 'emergency' situations), compact 7x22 Olympus in my handbag at all times, 6x30 Yosemite sitting near the window in my apartment and the Leudpold 7x42 I will use when going out.

great post LS

Since we all live in different evirons and are surrounded by varying habitat, I would suspect it would be up to each individual to decide on their optimized magnifications. Around my house with its wooded nature, a 6.5 or 7x is best all around unless I drive somewhere. I would like to have some wide open vistas where I could tripod mount some 15x70's or 20x80's and have a go at it, but thats not in the cards at my house. Until then I'll have to make do with my 6.5, 7, 8, 10 & 12x's.

Looksharp,
Thanks for your thoughts, which you presented very well. Any enthusiast must have furrowed his or her brow over this question.

Your philosophy makes perfect sense, if you can only predict at what distance birds will be visible. It seems like most places I go, however, they can pop up anywhere. So, I would seem to be a perfect candidate for the 8x compromise, which in fact I used to swear by. I do have a nice 8x but rarely use it. A period that I spent with 12x full time turned my head around to the possibilities and advantages of high magnification. I now choose a 10x for almost all outings, and regard it, which you might consider the top useful power, as my compromise. 7x or 8x just doesn't thrill me much, visually. I'm not pretending 10x is great for everything, however. I do miss a few at extreme close range. But while 10x is hardly necessary to ID a bird 20 feet away, it does make them look gloriously big. For me, birding is not so much the business of making IDs, as getting great views of the beautiful creatures.

I would like to paraphrase something that Benjamin Franklin wrote, since I don't remember it word for word. It seems appropriate here. It is good for a man to be reasonable, so that he can give good reasons for doing the things he wants to do.
Ron