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- The nominal luminous power of the binoculars: (2 Viewers)
- Thread starter Rico70
- Start date
Not many birding bins in that lot!
It seems logical to me! ... which birder is interested in twilight binoculars?
If you want a Pileatus's list, you will need to list everything you want.
But I don't have all the binoculars in my table, and especially the 8x42 which are the most useless format among all the formats.
I have everything I want and my 8.5X42 is very useful!It seems logical to me! ... which birder is interested in twilight binoculars?
If you want a Pileatus's list, you will need to list everything you want.
But I don't have all the binoculars in my table, and especially the 8x42 which are the most useless format among all the formats.
Many birders are interested in twilight bins...I thought you knew that.
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but it is you who commented exactly the opposite, in #82 ... I thought you understood it for yourself.
I don't care what the birder wants, this is the forum of binoculars, therefore of all binoculars, which work for all users (not just for birders), also for women and children, like for astronomers and hunters, or for the military, or anyone interested in binoculars and also for all ignorant and incompetent, independently. Binoculars are for everyone!
Come down from the clouds, you are not a bird!
... and above all, stop provoking, that you are not even capable!
if this topic doesn't interest you, go elsewhere, Thank you
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Rico, what should one use for stargazing in a light polluted area? Is the choice different for a very dark site?but it is you who commented exactly the opposite, in #82 ... I thought you understood it for yourself.
I don't care what the birder wants, this is the forum of binoculars, therefore of all binoculars, which work for all users (not just for birders), also for women and children, like for astronomers and hunters, or for the military, or anyone interested in binoculars and also for all ignorant and incompetent, independently. Binoculars are for everyone!
Come down from the clouds, you are not a bird!
... and above all, stop provoking, that you are not even capable!
if this topic doesn't interest you, go elsewhere, Thank you
wdc
Well-known member
I keep wanting to think its the translating software that is the fly in the communications ointment, that someone like Roberto Benigni, from Life is Beautiful, is sincerely trying to share some deep insight about optics, and that nugget of wisdom is getting mangled on its journey through the ether, but I'm more convinced its pure, un-adulterated ego that is in play. As one perceptive forum member speculated awhile back, perhaps the individual has already been banned from all the optics forums in his native language.
I have spent 25 years in the film business and have witnessed amazing displays of arrogance, in person, from the heads of the studio on down... That it is a regular occurrence on the internet, is not so surprising, since there is a cloak of anonymity, and 'anyone' can broadcast their manifesto to the entire world, and call everyone who disputes their ideas an idiot. Some folks just love nothing more than a captive audience to preach to.
rant off.
Can't wait to go birding on the weekend...
-Bill
I have spent 25 years in the film business and have witnessed amazing displays of arrogance, in person, from the heads of the studio on down... That it is a regular occurrence on the internet, is not so surprising, since there is a cloak of anonymity, and 'anyone' can broadcast their manifesto to the entire world, and call everyone who disputes their ideas an idiot. Some folks just love nothing more than a captive audience to preach to.
rant off.
Can't wait to go birding on the weekend...
-Bill
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This is the formula:
(A^2/M*0,7854)^((T%/100)^2,8) * ((Q/10)^0,25)
A = aperture, M = magnification, T%= transmittance, Q = quality coefficient
This formula takes into account the exact value of the "pln" (not simplified), which will be exposed to the power of the Transmittance coefficient, in order to make a difference value of every 3% T, equivalent to 20% of the pupillary surface or 20% magnification. For this I did various empirical tests and then I rounded the values based on a most coherent result.
All this is multiplied by the quality coefficient (Q), which affects only 5% on the general value (low involvement).
Explaining how the Q coefficient is calculated is too complex, since it is the result of the ensemble of 4 other formulas, each one variously complex.
It would be very interesting to have the T% data, extrapolated from a single evaluator-examiner (eg, GvG), who however used the same method and the same instrumentation, for each binoculars present in the list.
(A^2/M*0,7854)^((T%/100)^2,8) * ((Q/10)^0,25)
A = aperture, M = magnification, T%= transmittance, Q = quality coefficient
This formula takes into account the exact value of the "pln" (not simplified), which will be exposed to the power of the Transmittance coefficient, in order to make a difference value of every 3% T, equivalent to 20% of the pupillary surface or 20% magnification. For this I did various empirical tests and then I rounded the values based on a most coherent result.
All this is multiplied by the quality coefficient (Q), which affects only 5% on the general value (low involvement).
Explaining how the Q coefficient is calculated is too complex, since it is the result of the ensemble of 4 other formulas, each one variously complex.
It would be very interesting to have the T% data, extrapolated from a single evaluator-examiner (eg, GvG), who however used the same method and the same instrumentation, for each binoculars present in the list.
Well Steve, I have already given a great value to T%, but its power will always be much less influential than the "pln" value and therefore, "M+A" will direct the results much more: a 10x70 = 490pln, while a 7x42 = 250pln.
Peter, the ordering is correct, but I have no idea what’s the uncertainty. I can only say that the first 25 binoculars, are in a relative score range of about 16% (15.6%) of the total. But since the finished formulas are compressed to a uniform value to work between on average about 65 and 130 points, I can't answer you adequately.
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This is another "vision" of my table, which I have adapted to include only 6x-12x binoculars with central focus in the most common formats.
As before, the two images catalog the first 50 "brightest" binoculars of this group respectively (25 + 25).
Unfortunately, the T% values are what they are (not all coherent): some follow the declarations given by the manufacturer, while others follow the data that I collected from the sparse evidence of those who published on their own the measurements. For all the other models without declarations, I assigned T% values that are on average consistent with the price and the quality of the binoculars.
As before, the two images catalog the first 50 "brightest" binoculars of this group respectively (25 + 25).
Unfortunately, the T% values are what they are (not all coherent): some follow the declarations given by the manufacturer, while others follow the data that I collected from the sparse evidence of those who published on their own the measurements. For all the other models without declarations, I assigned T% values that are on average consistent with the price and the quality of the binoculars.
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"Explaining how the Q coefficient is calculated is too complex" is not an acceptable argument.
Also, please describe your empirical testing methodology...in detail.
More guessing?
Steve C
Well-known member
The thrust of this seemed to be to arrive at a luminous power (pln) number. The binoculars are ranked by giving them a percentage value. That would be, say 92% of what? The rankings don't seem to be consistent from highest % to lowest. Why is that, am I missing something (this is likely since I have a headache right now)? I note the Maven B 2 7x45 (a binocular I have some extensive hands on time with and the original placement seemed to match relatively well with it and others on the list which I had familiarity with) was present with a pretty high score in your first table, but is missing from the second one. Just missed it in the second go around, or is there another reason? Or can we take it your original rank is still valid, in your opinion?
The idea that 8x42 is a useless format will raise more than a few eyebrows. Please run some through your formula and post results to prove your point.
The idea that 8x42 is a useless format will raise more than a few eyebrows. Please run some through your formula and post results to prove your point.
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No Steve, this is not a point. Each binocular has its own usefulness or uselessness according to each user. For me, any 8x40-42 has no use. But I can understand who uses it and considers it useful or even the most useful.
I am not clear about your question, but I try to hypothesize a couple of answers:
- 92% of Transmittance (T%), which is the measurement in this case referred to the light energy (the electromagnetic energy of Light) that can pass through the binoculars and that reaches the user's eye. Of the initial 100%, only 92% pass (for example).
- the values readable in the table correspond to the T% value declared by the manufacturer (in blue), found in other specifications (in orange or yellow) or attributed according to quality and price (with no value).
Yes, I already answered you in this:
"Well Steve, I have already given a great value to T%, but its power will always be much less influential than the "pln" value and therefore, "M+A" will direct the results much more: a 10x70 = 490pln, while a 7x42 = 250pln."
Steve, you asked me for the formula, which I kindly gave you, but you didn't even read it. You asked me a lot of other questions, but it seems that you don't even read the answers.
I'm probably trying to be polite by answering the various questions in topic, but it seems that on the other side there is little interest in understanding the answers (tell me if I'm wrong).
And if so, it would only be a great sadness. :-C
From the second list (6x-12x) I also excluded all twilight binoculars with exit pupil greater than 6mm, to add more ideal models for the birders too.
Troubador
Moderator
Rico
This is indeed a forum for binoculars but its on a website called Birdforum. This site is primarily for birders although anyone with an interest in binoculars is welcome to join in, but they should not be surprised if most binoculars and theories about binoculars are scrutinised from a birder's point of view.
Lee
Moderator
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WJC
Well-known member
Or from the standpoint of a birder who has spent a lifetime in optical design, manufacturing, repair, calibration, and collimation and who can spot opto-irrelevance from a mile away. :cat:
Bill
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Troubador
Moderator
especially the 8x42 which are the most useless format among all the formats.
Since to many birders on Birdforum an 8 or 8.5x 40mm or 42mm is perhaps the most versatile binocular format and the choice of many who can only afford one binocular, maybe you can an understand why your joke was not appreciated.
Lee
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