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- Magnification and move vision:

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Old Saturday 4th January 2020, 23:16   #26
Rico70
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Omid, I want and will want to take-collect only the interesting parts of what you say.
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Originally Posted by Omid View Post
... a good 12X50 (e.g. Leica Trinovid) will provide more detail of course but it is heavy and needs a solid rest.
Finally, as you said yourself in you latest post, very narrow field of view of high-power instruments (e.g. spotting scopes) makes their utility very limited.
As I have already said, it is logical that binoculars with higher magnification will be physically larger and heavier (greater tonnage) and will tend to have an increasingly narrow field (unfortunately).

But there was no need to repeat it.

Omid, if you really want to participate in the discussion with me (without controversy), you could try to avoid unnecessary nonsense. If you are interested in the topic, I am sure you will have interesting questions and answers, like all the others. Let's leave the controversies at home.
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Old Sunday 5th January 2020, 00:06   #27
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I was using the Canon 10x42L IS yesterday...
...I doubt that any hand held unbraced binocular would equal it.
I believe you! ... but I would like to do a detail reading comparison against binoculars of the same weight, built according to my specifications (with the same price).
I am still convinced that it is possible to read the same detail as your Canon, without stabilization, but of course with a longer reading time (for example, a license plate of the distant car).
By the way, I have a good 7x50 with fantastic ergonomics and excellent collimation, but in direct comparison with any 10x, even inexpensive, the reading of the sign "do not place motorbikes and bicycles" at 80m distance, will always be faster and more resolute with 10x.

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Originally Posted by Binastro View Post
As to the whole discussion here, it reminds me of Galileo's opinion against the religious leader's viewpoints.
Looking at the night sky, it really doesn't matter whether the Sun goes round the Earth or the Earth goes around the Sun.
This comparison is an honor for me. But, I hope not to burn likeGiordano Bruno

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Originally Posted by Binastro View Post
... It doesn't matter why the image in hand held binoculars moves, it just does.
Of course, for you, but not for everyone! ... this is their discussion.

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Originally Posted by Binastro View Post
The OP finally admits to bracing the 25x binocular.
Why, if hand holding the binocular is so straight forward, and even 100x binoculars are considered as hand held instruments?
Because it is paradoxically more difficult to use 10x than 100x!

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Originally Posted by Binastro View Post
The hypothesis that increases of 3.24x or 3x are necessary to see more detail seems at odds with practice.
1.5x seems more likely in the real world...
You keep confusing "popular offer" and "boundary conditions".
Also the criterion of Rayleigh (1,22x) and the criterion Nyquist's (2x) are two more criteria that probably you never have knew anything about.
For once, can't you do 2+2 about the need to have at least 3 pixels (or 3 photoreceptors) to generate a complete spatial information of two white lines alternate of a test "black/white" or two separate stars?

Last edited by Rico70 : Sunday 5th January 2020 at 22:12. Reason: translate
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Old Sunday 5th January 2020, 00:29   #28
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Quote:
Originally Posted by Steve C View Post
I don't doubt that higher magnification and resolution are pretty well joined at the hip.
Hi Steve, this is a great start!

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Originally Posted by Steve C View Post
However, it seems to me that if you compare an 8x42 and a 10x42 of the same make and model, that we are asking more work (magnification) from the same amount of light energy (what falls on the objective). It always seems to me that in the above scenario that the 8x is a bit sharper.
Here it really depends on what you mean by "sharper".
If you mean "higher resolution of details", I answer that it is only your appearance-imagination. Which comes into logical conflict with your first sentence (which was "a great start" instead).
If, on the other hand, you mean "cleaning the image" from AC and other optical dirt, in this case I say that it depends too much on the binoculars project and therefore nothing can be generalized (it becomes subjective and therefore useless, without being able to specify case by case).

Leave the thought that a "greater exit pupil" (or greater aperture) is synonymous with greater resolution, in the binocular field. Indeed, it is generally a symptom of greater optical aberrations and greater aberrations of the eye. So, no 8x42 will see better details than a 10x42, if both are built to the best of their ability.
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Seems like the ratio of light energy to magnification (same size exit pupil) has to play into the equation, not just magnification by itself.
Of course, in this case I can't deny. But don't confuse "8x42 vs 10x42" in daylight, where the only theoretical difference is precisely the magnification.
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Old Sunday 5th January 2020, 15:20   #29
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I will give personal thoughts here.

I cannot see through other people's eyes, only my own eyes.

In general, I think that the oscillations from hand holding a binocular are a rough circle with possibly additional darting movements.
As the magnification increases the apparent size of the rough circle increases.

With a 100x binocular the field is about the size of the Moon, about 0.5 degrees.
Looking at a nearly full moon I think that most of the time the moon would be in the field hand holding the 100x binocular.
One may get glimpses of say 1/30th second duration where quite fine detail is seen, finer than a hand held 10x binocular.

However, if the 100x binocular was firmly mounted on a good tripod finer detail would be seen, and the reliability of that detail would be high.

The reasonably fine detail hand holding the 100x binocular, glimpsed for perhaps 1/30th second, would have a low reliability.

The reliability of the detail hand holding a 10x binocular would be high, even though a little blurred.

Mistakes using glimpsed detail for small fractions of a second are numerous.

I would give a very low value to any detail in an observation made with a hand held 100x binocular.
As a section director of a national astronomy association, I would just exclude any observation made with a hand held 100x binocular because it had too low a reliability.
In fact I have never had such an observation submitted to me, or seen any such observation in any world recognised astronomy group in the last fifty years.

Regarding post 27.
I don't speak Italian.

The last paragraph is insulting.

We have had theorists here before, trying to convince us of their take on the optical world.
When the theories don't agree with actual empirical results, personally I don't take the theories as having much weight.

B.
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Old Sunday 5th January 2020, 15:50   #30
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Rico 70,
I followed the discussion a bit and my understanding is, that you are able to hand hold binoculars with magnifications more than 8x, so lets say 15x, 20x, 25x etc. so steady that you are able to observe objects perfectly sharp without vibration unsharpness /perfect resolution?
Did I understand that correctly?
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Old Sunday 5th January 2020, 17:07   #31
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Rico

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Certo, per te, ma non per tutti! ... questa è la loro discussione.
Perché è paradossalmente più difficile usare 10x che 100x!

Post in English please. It is ok to use occasional words from other languages but answers and comment like this should always be in the English language.

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Old Sunday 5th January 2020, 20:08   #32
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I assume that Rico simply overlooked those two lines in running the translator. Google does a good job:

Certo, per te, ma non per tutti! ... questa è la loro discussione.
Of course, for you, but not for everyone! ... this is their discussion. [i.e. it's for them?]

Perché è paradossalmente più difficile usare 10x che 100x!
Because it is paradoxically more difficult to use 10x than 100x!

The latter is an interesting argument Rico has made before, though I'm not convinced.
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Old Sunday 5th January 2020, 22:16   #33
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Post in English please. It is ok to use occasional words from other languages but answers and comment like this should always be in the English language.
I just corrected, thanks Lee for the report. They had escaped!
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Old Sunday 5th January 2020, 22:33   #34
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you are able to hand hold binoculars with magnifications more than 8x, so lets say 15x, 20x, 25x etc. so steady that you are able to observe objects perfectly sharp without vibration unsharpness /perfect resolution?
I think "perfectly sharp" is not the correct term.
I prefer to say that the 25x vision is sharp enough to see 3 times larger and 3 times more detail than the 8x.

So is it clearer?
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Old Sunday 5th January 2020, 22:43   #35
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Rico70, post 34,
No it is not clearer to me, since with a handhold binocular at 25x magnification small objects are more "blurred" than when supported, so details are less clear (sharp).
Are you familiar with very solid published studies with regard to this matter by different reserach groups? I ask it, since we discussed this some time go also on BF.
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Old Sunday 5th January 2020, 23:34   #36
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Gijs,

post 35.

I am with you here.

3 times larger, 25 times compared to 8 times.
Yes it is.

3 times more detail than 8x.
No it isn't.
At least not hand held.

I have no objection at all to anybody using a 25x70 binocular hand held unsupported or braced.
But to say that 3x more detail is seen than at 8x is I think not found by any studies.

Claims have to be verified by ones peers.

Regards,
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Old Monday 6th January 2020, 00:03   #37
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Regarding post 27.
I don't speak Italian.

The last paragraph is insulting.
Sorry for the Italian. It is not my will to offend you, never.
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Old Monday 6th January 2020, 00:04   #38
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Because it is paradoxically more difficult to use 10x than 100x!

The latter is an interesting argument Rico has made before, though I'm not convinced.
I can understand you Tenex, I never would have thought it, without seeing it with my own eyes.
I'm not sure how to explain it, but keep in mind that the 10x's micro-shake is sufficiently visible observing a star in the night sky, but it is impossible to "counter-react (solve)" with your hands or eyes, because it is a too much fine-small figure. In fact, the Moon (30') with 10x is clearly visible without blur.

I don't know how much the "10x figure" can measure in arc seconds, because I never measured it (but then each one will have a different subjective value, different in different circumstances). I only know that once that figure becomes 10 times greater (with 100x) it is no longer a micro-shake, but a large-wide movement, which the eye is able to react and stabilize with its "tricks".

The final feeling is that, although the vision of the visual field is constantly moving, because we are trying to support a 100x binoculars freehand, the vision of the details of the 100x are revealed to the eye, in a much better way than what is possible see in proportion with 10x. I'll give you an example: of the Pigeon on the ledge about 80m away I could see the dried poop on the legs and all the nuances of the wrinkles of the orange skin. I tried to mount the 25x on the tripod and I couldn't even get the feeling that the legs were dirty with dry poop. I could only see that it was a pigeon perched on the ledge.

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Old Monday 6th January 2020, 00:26   #39
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say that 3x more detail is seen than at 8x is I think not found by any studies.
Why, instead you have studied the thing and therefore you can pronounce on it?
So pass me the physical law which explains the phenomenon you affirm, refuting what I say. I want to read it reported by a book of Physics for university study, not by the blogger "quiquoqua of my boots".

Or since you proceed only for empiricism, you cannot make use of any theoretical physical law, because the other theorists of the forum have already burned them (?!)



Do you think you're less offensive than me?

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Old Monday 6th January 2020, 00:32   #40
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with a handhold binocular at 25x magnification small objects are more "blurred" than when supported, so details are less clear (sharp)
Okay, and is there a need for solid research to understand this?
This applies to any magnification!

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Old Monday 6th January 2020, 00:58   #41
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Quote:
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Okay, and is there a need for solid research to understand this?
This applies to any magnification!
Hi, Rico70,

I certainly don’t want to get in trouble with you, as I have my hands full with another on this forum. So, I will make it short:

There is no need for solid research on this.

— A 7x binocular (without a tripod) vibrates to a degree 7 times greater than one not using the bino.
— A 10x binocular (without a tripod) vibrates to a degree 10 times greater than one not using the bino.
— A 25x binocular (without a tripod) vibrates to a degree 25 times greater than one not using the bino.

A room full of Ph.Ds. do not have the horsepower to say anything different. How the body handles the vibrations may be slightly different. However, the instruments will vibrate to the degree mentioned above.

Cheers,

Bill
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Old Monday 6th January 2020, 05:15   #42
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Hi, Rico70,

I certainly don’t want to get in trouble with you, as I have my hands full with another on this forum. So, I will make it short:

There is no need for solid research on this.

— A 7x binocular (without a tripod) vibrates to a degree 7 times greater than one not using the bino.
— A 10x binocular (without a tripod) vibrates to a degree 10 times greater than one not using the bino.
— A 25x binocular (without a tripod) vibrates to a degree 25 times greater than one not using the bino.

A room full of Ph.Ds. do not have the horsepower to say anything different. How the body handles the vibrations may be slightly different. However, the instruments will vibrate to the degree mentioned above.

Cheers,

Bill
I'm w/Rico70 on one detail. All else being equal, I don't think that it's correct to say a 25x binocular vibrates more than a 7x bin which vibrates more than a 1x bin. The 7x bin simply shows the vibration magnified 7x more than the 1x.

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Rico70, post 34,
...with a handhold binocular at 25x magnification small objects are more "blurred" than when supported, so details are less clear (sharp)...
How much detail can be seen (i.e. captured by the eye and understood by the brain) in the shaky 1x versus shaky 7x view is complicated. The 7x (of a bin with high resolving ability) reveals many details beyond the resolving limit of the eye at 1x, and the amount of apparent motion is modest enough that much of this detail is within the processing limits of the retinal ganglia and brain, so the 7x view is more useful than the 1x view even if, when shaky, it doesn't provide a full 7x more detail than the 1x. The 25x potentially delivers even more detail to the eye, but if the apparent motion of the image is high enough (i.e. apparently fast enough), it may be beyond the processing abilities of the retina and brain, and so much of it will not be perceptible. In a worst case scenario, one wouldn't even be able to understand the same level of detail that was available at 7x. For the details I need to ID birds at typical target acquisition distances when birding, a 7x is generally sufficient and enjoyable, whereas the view through a 25x would be hard to aim, focus, and interpret.

--AP

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Old Monday 6th January 2020, 08:09   #43
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Originally Posted by Alexis Powell View Post
I'm w/Rico70 on one detail. All else being equal, I don't think that it's correct to say a 25x binocular vibrates more than a 7x bin which vibrates more than a 1x bin. The 7x bin simply shows the vibration magnified 7x more than the 1x.



How much detail can be seen (i.e. captured by the eye and understood by the brain) in the shaky 1x versus shaky 7x view is complicated. The 7x (of a bin with high resolving ability) reveals many details beyond the resolving limit of the eye at 1x, and the amount of apparent motion is modest enough that much of this detail is within the processing limits of the retinal ganglia and brain, so the 7x view is more useful than the 1x view even if, when shaky, it doesn't provide a full 7x more detail than the 1x. The 25x potentially delivers even more detail to the eye, but if the apparent motion of the image is high enough (i.e. apparently fast enough), it may be beyond the processing abilities of the retina and brain, and so much of it will not be perceptible. In a worst case scenario, one wouldn't even be able to understand the same level of detail that was available at 7x. For the details I need to ID birds at typical target acquisition distances when birding, a 7x is generally sufficient and enjoyable, whereas the view through a 25x would be hard to aim, focus, and interpret.

--AP
Agreed.

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Old Monday 6th January 2020, 08:48   #44
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Rico70, post 40,
In answer to your question: is it necessary to investigate this? Yes there was especially for the military, since it is of importance to know how well defined the image of your observed object is in order to be sure that you aim exactly at the right spot. That was even more important for the infantry in the old days, since soldiers had to run fast to escape military observation and gunshots. Therefore soldiers in the old days were equipped with 6x30 porro binoculars (after running your muscle system is kind of tense and you are breathing with higher frequency)so they would obtain a blur-free image of the opponent.
But the outcome of these studies are just as well applicable to birders.
Image stabilisation in binocular systems has overcome that to a large extent.
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Old Monday 6th January 2020, 13:08   #45
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I just counted up as many 15x and higher magnification binoculars that I have actually used for either terrestrial or astro observations.
These are all different types not duplicates.
I am currently up to 31 different types.
There may be a few more.
I am not unfamiliar with high powered binoculars.
They are almost never tripod mounted, but supported as well as possible by whatever is handy.

Short glimpsed observations using very high magnifications hand held will show detail, but it is tiring, and unreliable.

One only has to use a Canon 18x50 IS binocular for limiting views of Jupiter's moons.
With the stabilizer off one may see, say two or three moons.
One can be pretty certain of these.
When the stabilizer is switched on, suddenly one of the moons is seen to be actually two very close moons seen as one.
This is not even suspected with the stabilizer off.

Usually the Canon 10x42L IS shows Jupiter's moons just as well as the 18x50 IS.
But sometimes a further moon is suddenly seen almost touching Jupiter's limb with the 18x50 IS, which was not suspected with the 10x42L IS.

As to 'flags' on aircraft.
I see these routinely at 2kms without a binocular.
With an 8x or 10x binocular at 10 to 15kms.
With the Canon 18x50 IS, further.
But the flags differ in size and how easily they are seen.
It also depends on the orientation of the aircraft.
I routinely see the windows on aircraft with stabilized binoculars.

However, someone using the Takahashi 22x60 binocular, tripod mounted, says he saw the people inside the aircraft through their windows.
I am not sure if I have seen this with the Canon 18x50IS.

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Old Monday 6th January 2020, 13:41   #46
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I sometimes wonder if observation has any value in Internet debates.
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Old Monday 6th January 2020, 15:01   #47
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I sometimes wonder if observation has any value in Internet debates.
I can't be sure to what you are referring, but I think that Rico70 and most of the rest of us are talking past each other because we are interested in obtaining different things from our observations. Rico70 is in love with the fact that it is possible to see (even if only as a momentary glimpse) details with a hand-held 25x binocular that a 7x will never reveal to the eye. Most of the rest of us are more interested in using bins that resolve a level of detail that matches the maximum amount that we are able to see reliably through a typically shaky hand-held view, even at the cost of not being able to see the higher levels of detail that could be glimpsed with higher hand-held magnifications. In my own case, as explained in my original response in this thread (post #2), the reason for my lack of interest in high magnifications in a general purpose birding binocular is that I simply have _no need_ to see those details with which Rico70 is so enamored. As a birder, my interest is in bird identification, and in identifying as many species as possible in a day. At the distances at which a birder typically first takes notice of a bird, most are already identifiable at 7x (or 8x or 8.5x or 10x). Using a higher magnification such as 25x would be counterproductive and result in identifying many fewer birds since it would come at the expense of FOV, DOF, focus speed, and easy handling. I further argued that magnification is not a very important specification when it comes to birding binoculars. Choosing between, say 7x and 10x, is of little practical consequence for birding when it comes to costs/benefits of magnification itself. Rather, the confounded effects on FOV, DOF, and focus speed are more important. In birding situations that demand more magnification than 7x for identification (because the birds are first detected much farther away than is typical, and because they may not be approachable, e.g. on a mudflat or at sea or distantly on a lake), the increased detail available from a 10x bin will deliver a few more birds than does 7x, but in my experience, many birds in these situations will still be too far away (In other words, it is rare that the marginal increase in detail of 10x over 7x just happens to be just enough to deliver the detail needed to identify all the birds detected). In those cases, I employ a tripod-mounted scope, and typically, 30x is enough to do the job (i.e. to allow for identification of all birds detected), but sometimes higher powers are useful.

--AP

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Old Monday 6th January 2020, 15:14   #48
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I can't be sure to what you are referring, but I think that Rico70 and most of the rest of us are talking past each other because we are interested in obtaining different things from our observations. Rico70 is in love with the fact that it is possible to see (even if only as a momentary glimpse) details with a hand-held 25x binocular that a 7x will never reveal to the eye. Most of the rest of us are more interested in using bins that resolve a level of detail that matches the maximum amount that we are able to see reliably through a typically shaky hand-held view, even at the cost of not being able to see the higher levels of detail that could be glimpsed with higher hand-held magnifications. In my own case, as explained in my original response in this thread (post #2), the reason for my lack of interest in high magnifications in a general purpose birding binocular is that I simply have _no need_ to see those details with which Rico70 is so enamored. As a birder, my interest is in bird identification, and in identifying as many species as possible in a day. At the distances at which a birder typically first takes notice of a bird, most are already identifiable at 7x (or 8x or 8.5x or 10x). Using a higher magnification such as 25x would be counterproductive and result in identifying many fewer birds since it would come at the expense of FOV, DOF, focus speed, and easy handling. I further argued that magnification is not a very important specification when it comes to birding binoculars. Choosing between, say 7x and 10x, is of little practical consequence for birding when it comes to costs/benefits of magnification itself. Rather, the confounded effects on FOV, DOF, and focus speed are more important. In birding situations that demand more magnification than 7x for identification (because the birds are first detected much farther away than is typical, and because they may not be approachable, e.g. on a mudflat or at sea or distantly on a lake), the increased detail available from 10x bin will deliver a few more birds than does 7x, but in my experience, many birds in these situations will still be too far away (in other words, it is rare that the marginal increase in detail of 10x over 7x just happens to be just enough to deliver the detail needed for all the birds detected). In those cases, I employ a tripod-mounted scope, and typically, 30x is enough to do the job (i.e. to allow for identification of all birds detected), but sometimes higher powers are useful.

--AP
I also use 7/8/10X bins and we used an ED82/30X scope for more than 10 years until I broke down and purchased a 25-75 zoom and later a new Kowa 883 with zoom. Your personal observations, developed over a number of years, are virtually identical to mine.

Regarding handshake...
I purchased a 10X50 Swarovision to use for stargazing and immediately constructed a mount for it. The difference between handheld and stabilized views of the stars is like on/off. One works, the other doesn't. Daytime use is obviously different but the same rule applies...handshake eventually renders the image useless.

The image shows a mounted 7X42 SLC.
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Old Monday 6th January 2020, 15:19   #49
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Pileatus,

Nice mount and counterweight.

I suppose the controller is to bring the binocular to the eyes. (:

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B.
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Old Monday 6th January 2020, 15:34   #50
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Pileatus,

Nice mount and counterweight.

I suppose the controller is to bring the binocular to the eyes. (:

Regards,
B.
The Manfrotto ball head mount allows full and precise movement. Basic operation requires a few manipulations that can be performed in the dark.

A few more views...
The smaller mount is for my wife's 8X32 SV.
The other photo shows the 10X50 SV mounted. The SV's IPD can easily be adjusted by loosening the wing nut. The bin is safe and secure.
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Last edited by Pileatus : Monday 6th January 2020 at 15:41.
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