New Leica HD Ultravid PLUS (1 Viewer)

brocknroller · Sep 23, 2014

ceasar said:
Right Brock,

Maybe I should have advised that couple I saw on the deck who were using those 828s while taking a Birding tour at the Cape May lighthouse last spring that they might not be getting near enough pleasure from their experience because of the dimness of the binoculars they were using? As I recall the day was lightly overcast and somewhat windy.

After all, they probably could have afforded much better. I think they drove up in a late model Acura.

Bob

Pretzel logic, Bobby boy! The fact that he owed modestly priced 828s with "average light transmission" (still think that was a translation glitch) and an above average priced car does not in any way reflect on the value of the binoculars.

It reminds me of the rich couple who threw me out of their luxury home (literally threw my vacuum cleaner demo boxes out into their driveway) and nearly slammed the door on my butt, after I failed to deliver a steak knife set that the telemarketer promised them who set up my home demonstration of a $1,500 Filter Queen HEPA filter vacuum cleaner (I arrived with a 24-pack case of Pepsi, because the office ran out of steak knives). As I picked up my gear, I stared at their shiny, late model Mercedes.

After months of "sticking my foot in the door" of strangers' homes to sell them an overpriced vacuum cleaner that could beat the pants off their Kirby, my dealer and our crew realized that it was useless trying to sell a high value vacuum cleaner to the rich, because they couldn't put it on display, but had to stick it in the closet where nobody could appreciate its beauty or luxury. Whereas the Merc, well, it shone proudly in the half circle driveway and wherever they drove it.

I think that's probably the explanation behind why they had $300 Swift 828s for bins but a $48,000 Acura RLX for a car.

Also, they probably have maximum entrance pupils of 3mm, so better low light performance wouldn't mean that much to them.

Anyway, I can see that you're never going to admit defeat and will continue to champion a "disappointing light performance" roof, so let's go with your explanation. Now let's see if Swift and Acura are interested in using that couple for a cross-promotion TV commercial.

Brock

ceasar · Sep 23, 2014

brocknroller said:
Pretzel logic, Bobby boy! The fact that he owed modestly priced 828s with "average light transmission" (still think that was a translation glitch) and an above average priced car does not in any way reflect on the value of the binoculars.

It reminds me of the rich couple who threw me out of their luxury home (literally threw my vacuum cleaner demo boxes out into their driveway) and nearly slammed the door on my butt, after I failed to deliver a steak knife set that the telemarketer promised them who set up my home demonstration of a $1,500 Filter Queen HEPA filter vacuum cleaner (I arrived with a 24-pack case of Pepsi, because the office ran out of steak knives). As I picked up my gear, I stared at their shiny, late model Mercedes.

After months of "sticking my foot in the door" of strangers' homes to sell them an overpriced vacuum cleaner that could beat the pants off their Kirby, my dealer and our crew realized that it was useless trying to sell a high value vacuum cleaner to the rich, because they couldn't put it on display, but had to stick it in the closet where nobody could appreciate its beauty or luxury. Whereas the Merc, well, it shone proudly in the half circle driveway and wherever they drove it.

I think that's probably the explanation behind why they had $300 Swift 828s for bins but a $48,000 Acura RLX for a car.

Also, they probably have maximum entrance pupils of 3mm, so better low light performance wouldn't mean that much to them.

Anyway, I can see that you're never going to admit defeat and will continue to champion a "disappointing light performance" roof, so let's go with your explanation. Now let's see if Swift and Acura are interested in using that couple for a cross-promotion TV commercial.

Brock

I'm not "championing" the 828 Brock. It is a perfectly useful binocular for its price. Why don't you reach into your pigs knuckle jar and buy a couple of inexpensive binoculars to keep and use for a while before you pass judgement on them? I do that and Frank does that.

You won't go broke.

Maybe then you could explain why Allbinos rates the Swift 828 right between the two Swift 820s despite the fact that they have transmission ratings 10 to 15 points more than the 828 does? Which is 85% and 90% for the 820s and 75% for the 828. This is clear evidence that you overrate the usefulness of brightness when you evaluate a binocular. You should spend more time using binoculars before you pass judgement on them.

http://www.allbinos.com/allbinos_ranking-binoculars_ranking-8.5x45.html

I posted this link in my response to Elk Cubs transmission charts in my post #102 which also has the comments about the couple using the 828s at Cape May and which is the one you take issue with here. In that post I commented on their respective transmission ratings. I don't know why you ignored it but then I'm not a journalist.

That's all I will say except I wish you the best of luck in winning a binocular in the Zen Ray raffles. I hope you keep it long enough and use it long enough to learn something about it.:t:

Cordially,

Bob

Troubador · Sep 23, 2014

Gijs van Ginkel said:
Lee, post 119,
That is an interesting topic: how many photons are necessary for the eye to generate a signal for the optical nerve. I touched that topic in my review paper on "Color vision etc. and from what I remember from the literature two photons are necessary for the optical system of the eye to generate an observation signal. It was already established in 1946 if my memory is still correct by investigations of Dr. Maarten Bouwman, who died recently. If you are really interestd I can probably find the data.
Gijs

Thanks for this Gijs

Could they really count individual photons in 1946?

And while only 2 extra photons may be registered via the optical nerve does this mean an instantaneous adjustment of the pupil is called for or does the 'system' tolerate this extra light to avoid constant adjustment of the pupil?

Lee

sako · Sep 23, 2014

Post #121

In a recent survey (forget what university over here actually did it) it was found that the rich are more likely to:
Steal money from the church plate (if they go to church).
Give the lowest tips.
Give the least amount to charity.
Complain the most about service.
Complain the most about prices when shopping.
Complain the most about just about everything.

I personally know a 70 something husband and wife who are multi millionaires and they buy most of their clothes from the local Salvation Army Op shop. They're always whining about something or another. If they knew what my binoculars cost I'd certainly get a lecture along the lines of a fool and his money are soon parted.

I guess once they drop off the hook they're going to leave their millions and all their property for their two offspring to squabble over.

Gijs van Ginkel · Sep 23, 2014

Lee, post 123,
We are talking here about Utrecht University where Bouwman worked, the absolute top of the scientific world, but I do not have to tell you that, since you are of course aware of this Scientific Paradise.
Gijs

Gijs van Ginkel · Sep 23, 2014

Lee,post 123,
I looked a little bit into the literature and there are different reports about the sensitivity of the optical system.
One report says: it is necessary that about six photons are absorbed almost simulataneously within the same small part of the retina.
Another report states that this may even occur with two photons simultaneously.
Signals which are more spread out in time or space are filtered away by the ganglion cells in the retina.
Ihave described this process in some detail on pages 14 and 15 in my review "Color vision, brightness, resolution and contrast in binocular images".
Gijs

Troubador · Sep 23, 2014

Gijs van Ginkel said:
Lee,post 123,
I looked a little bit into the literature and there are different reports about the sensitivity of the optical system.
One report says: it is necessary that about six photons are absorbed almost simulataneously within the same small part of the retina.
Another report states that this may even occur with two photons simultaneously.
Signals which are more spread out in time or space are filtered away by the ganglion cells in the retina.
Ihave described this process in some detail on pages 14 and 15 in my review "Color vision, brightness, resolution and contrast in binocular images".
Gijs

Gijs

Thank you for taking the time to look this up :t:

Lee

Binastro · Sep 23, 2014

Dear Lee and Gijs,

2 photons can be detected by skilled astronomers but only occasionaly, as a statistical event.
One needs to observe carefully with averted vision for say 5 minutes or more and if 3 occurences occur at the same position I take the star as glimpsed. This is with good young eyes. 4 times is better. I can't do this the last ten years as there are too many false events.
It may be possible to detect a single photon?

In the real world more photons are needed.

2 photons will not result in pupil chenge.

A photon checks into a hotel.
Do you have a room?
Yes Sir.
I'll take it.
I will get the porter to carry your luggage.
On no, that's not necessary.
I'm travelling light.

Troubador · Sep 23, 2014

Binastro said:
Dear Lee and Gijs,

2 photons can be detected by skilled astronomers but only occasionaly, as a statistical event.
One needs to observe carefully with averted vision for say 5 minutes or more and if 3 occurences occur at the same position I take the star as glimpsed. This is with good young eyes. 4 times is better. I can't do this the last ten years as there are too many false events.
It may be possible to detect a single photon?

In the real world more photons are needed.

2 photons will not result in pupil chenge.

A photon checks into a hotel.
Do you have a room?
Yes Sir.
I'll take it.
I will get the porter to carry your luggage.
On no, that's not necessary.
I'm travelling light.

Binny
How would you know how many photons you have glimpsed?

Nice joke BTW :-O

Do you know the one about the photon going into the bathroom through 2 doors at the same time to interfere with itself??? :-O

Lee

Gijs van Ginkel · Sep 23, 2014

Binastro, post 129,
Can you please supply me with an invitation to come to Oslo next year when you will receive the Nobel prize for Vision Physics, since you are to my knowledge the first person who can count photons by eye. I will take a couple of good Dutch beers for the celebration,
Gijs

sako · Sep 23, 2014

Pileatus said:
An unreferenced university survey?
Try this.
http://www.listener.co.nz/commentary/editorial/editorial-sweet-charity/
Or this.
http://www.nzherald.co.nz/business/news/article.cfm?c_id=3&objectid=10701310

Interesting. :t:

Binastro · Sep 23, 2014

Hi Lee and Gijs,
I think that by calculation 7.5 to 8.0 magnitude stars suggest that only one or two photons are hitting the eye when these are glimpsed.
There has been quite a lot of discussion in astronomy Journals regarding this over the last 30 years.
And also regarding the statistical distribution of photons arriving at the eye.
One cannot of course count individual photons.

Gijs, I can understand why you are bringing Dutch beer as Norwegian beer is so expensive.

elkcub · Sep 23, 2014

Gijs van Ginkel said:
Lee,post 123,
I looked a little bit into the literature and there are different reports about the sensitivity of the optical system.
One report says: it is necessary that about six photons are absorbed almost simulataneously within the same small part of the retina.
Another report states that this may even occur with two photons simultaneously.
Signals which are more spread out in time or space are filtered away by the ganglion cells in the retina.
Ihave described this process in some detail on pages 14 and 15 in my review "Color vision, brightness, resolution and contrast in binocular images".
Gijs

Gijs,

The original question was somewhat tricky since: (1) it referred to the number of photons necessary to trigger a response in the optic nerve, and (2) it didn't distinguish between rods and cones.

The rod receptors (the most sensitive) are now understood to be triggered by a single photon. I've come across this in several places, the most recent being the attached article. The authors say in the abstract: "...We provide unambiguous proof of single photon sensitivity of rod cells without relying on the statistical modeling..." Apparently, however, two or more rod outputs must then summate to trigger a ganglion cell output, which is the equivalent of an optic nerve signal.

I don't know the story for cone cells, but I believe several photons are needed to produce a receptor response, and again, summation at a ganglion cell produces the optic nerve signal.

A third type of photoreceptor, a specialized ganglion cell, was re-discovered in the 1990s that begins to answer some questions I've had for many years concerning pupillary response and dark adaptation. It may also hold a key for better understanding brightness/darkness perception.

Ed

Binastro · Sep 23, 2014

Thanks, saves my trawling through 30 years of Journals.

Gijs van Ginkel · Sep 23, 2014

Thank you Ed for the valuable addition, since it is of importance to distinguish between rods and cones since there is a great difference in sensitivity. For the use of binoculars in daylight however, we depend on cone vision, so sensitivity is determined by cone sensitivity.
Interesting is the light level in which rods and cones both are activated and I thought that the HT Schott glass was explicitly advised for use in these light levels, so our eyes could count more photons then with other glass types.
Gijs

elkcub · Sep 23, 2014

ceasar said:
I'm not "championing" the 828 Brock. It is a perfectly useful binocular for its price. Why don't you reach into your pigs knuckle jar and buy a couple of inexpensive binoculars to keep and use for a while before you pass judgement on them? I do that and Frank does that.

You won't go broke.

Maybe then you could explain why Allbinos rates the Swift 828 right between the two Swift 820s despite the fact that they have transmission ratings 10 to 15 points more than the 828 does? Which is 85% and 90% for the 820s and 75% for the 828. This is clear evidence that you overrate the usefulness of brightness when you evaluate a binocular. You should spend more time using binoculars before you pass judgement on them.

http://www.allbinos.com/allbinos_ranking-binoculars_ranking-8.5x45.html

I posted this link in my response to Elk Cubs transmission charts in my post #102 which also has the comments about the couple using the 828s at Cape May and which is the one you take issue with here. In that post I commented on their respective transmission ratings. I don't know why you ignored it but then I'm not a journalist.

That's all I will say except I wish you the best of luck in winning a binocular in the Zen Ray raffles. I hope you keep it long enough and use it long enough to learn something about it.:t:

Cordially,

Bob

Bob,

I've owned an 828 for about 10 years, and recommended it to several friends that have been quite pleased. They are casual users and not particularly critical of optics, so it hit their sweet spot for an affordable and robust pair of binoculars.

To some extent I think everyone tends to get sucked into believing that binocular rankings actually mean something. That's the basic premise. Measure k things, give each a number, add the numbers, and VOILA, something meaningful results. Then divide that by the largest total that could have been attained, and the result is transformed into a "percentage of perfection score," i.e., the POP score. At this point one's intellect has something tangible to defend or argue about, while avoiding the questionable veracity of the basic premise.

Last I heard, transmission measurement results in a set of numbers related to spectral bins (often 5 nm), — not a single number. I can't find a statement on Allbinos site that explains how they compute a single number, although I thought it was there. Can anyone help me out? Is it the peak value, the average value, the 555nm value, the inner-product with the visual sensitivity function? What?

Ed

elkcub · Sep 23, 2014

Gijs van Ginkel said:
Thank you Ed for the valuable addition, since it is of importance to distinguish between rods and cones since there is a great difference in sensitivity. For the use of binoculars in daylight however, we depend on cone vision, so sensitivity is determined by cone sensitivity.
Interesting is the light level in which rods and cones both are activated and I thought that the HT Schott glass was explicitly advised for use in these light levels, so our eyes could count more photons then with other glass types.
Gijs

Gijs,

It might also be pointed out that the largest number of cone cells (~65%?) are non-uniformly distributed outside the very small foveal area of the retina. Folks seem to have the mistaken impression that they are all concentrated at the fovea.

When Schott says: "...light level in which rods and cones both are activated," do they mean the mesopic level? Beats me how the glass could be tuned for that except by weighting red or blue transmission differently than for photopic viewing. That would also make it a specialized binocular, I guess.

My skepticism is working overtime on this one.

Ed

Gijs van Ginkel · Sep 23, 2014

Ed,
Yes, in the paper in which the HT glass was announced the Schott scientists explicitly hinted at the mesopic level, I will look for the paper tomorrow (it is time to go to bed here you know).
Gijs

Gijs van Ginkel · Sep 23, 2014

Ed, I found the paper just before taking a nap. It was published in 2011 and Dr. Ralf Jedamzik , optical glass specialist of Schott AG wrote in Optik & Photonik of May 2011: "" Improving light transmission of a glass by only a few percent can have a tremendous efffect on the quality of an optical system. A few percent transmittance improvement in the glasses used in binoculars, can significantly improve their mesopic vision capabilities".
Gijs

elkcub · Sep 23, 2014

Gijs van Ginkel said:
Ed, I found the paper just before taking a nap. It was published in 2011 and Dr. Ralf Jedamzik , optical glass specialist of Schott AG wrote in Optik & Photonik of May 2011: "" Improving light transmission of a glass by only a few percent can have a tremendous efffect on the quality of an optical system. A few percent transmittance improvement in the glasses used in binoculars, can significantly improve their mesopic vision capabilities".
Gijs

Thanks, Gijs. I would say Dr. Jedamzik's remark is probably a truism, since with higher transmission (accomplished by any means) the eye would not dark adapt as much and would thereby retain greater color vision capability. However, at dusk and dawn the illumination is changing continuously, so this "significant improvement" in mesopic vision would probably translate into only a few minutes of advantage — if it could be measured at all.

I guess the conundrum is that this particular type of glass transmits more because it absorbs less, so unlike increasing transmission with improved coatings, internal reflections are not necessarily reduced and the image enhanced. Brightness and image enhancement become independent variables. Depending on the coatings used, in fact, it is even possible for the image to degrade, even though brightness increases.

It doesn't sound to me like it's worth the effort, although it might make a good sales pitch in some circles.

Ed

New Leica HD Ultravid PLUS (1 Viewer)

porromaniac

Well-known member

Moderator

Well-known member

Well-known member

Well-known member

Moderator

Well-known member

Moderator

Well-known member

Well-known member

Well-known member

Silicon Valley, California

Attachments

Well-known member

Well-known member

Silicon Valley, California

Silicon Valley, California

Well-known member

Well-known member

Silicon Valley, California

Similar threads

Users who are viewing this thread