He always tries to baffle us with BS. Problem with that strategy is that most everyone here has caught on to his tactics, which are laughable. The dude has become a clownshow.
-
Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.
Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
A Zeiss Conquest HD on steroids. (1 Viewer)
- Thread starter [email protected]
- Start date
Yes, but tell me where I can buy a 50x20, 50x50 0r a 100x50 binocular? That doesn't make sense because there is no binocular made in those formats. Twilight factor simply means you can see more detail in lower light when the magnification is higher, the same way you can in daylight. It is useful for that reason.
Last edited:
What I want to point out is that the twilight factor is not a mathematical formula that can be used indiscriminately to describe low-light performance.
If you say that a 10x50 is 4 times brighter than a 10x25, that is correct. Because it is a fact.
But if you say that an instrument with twilight factor of 40 means it's better in low light than one with 20, that alone is not a fact. It can be true but it can also be the opposite. It all depends on the magnification and exit pupil.
In many cases, perhaps most, a 10x40 is better in low light than a 7x35. The higher magnification often wins even though the image is noticeably dimmer. But here the difference of exit pupils is quite small.
You say:
"Twilight factor simply means you can see more detail in lower light when the magnification is higher, the same way you can in daylight. It's useful for that reason."
That's not a correct statement because you describe it as being a law, like relative brightness.
And if it's the same way in daylight, that means it's not really about low-light performance.
Higher magnification ALWAYS reveals more detail as long as there is enough light to see details. Of course, provided that the air and the optics allow it.
Maybe I'm picky, but I just want it right...
Last edited:
tenex
reality-based
+1
By now I can't help thinking that Dennis has fallen (again?) into something like the "costly signaling" of a peacock's tail. Lugging the 44.6oz/1264g of Conquest 8x56 shows what an optics connoisseur (or devoted birder) you are? Really? I sometimes carry 56s myself, but don't have to convince or justify it to anyone based on "immutable laws of physics" I'm embarrassed to have previously been ignorant of. I just like them, and sometimes need them for 15x. They also remind me in a nice way of the big Porro models I grew up with. They're worth trying if you haven't, if only out of curiosity, and when weight isn't a big issue, why not carry one? But when it is...
This piece too is just silly. Like Simpson at BVD (perhaps following him?) this author drew too many faulty inferences from astronomy which is a very different application. Was this some sort of fad 20 years ago: astronomers must know better than birders about optics? Not for daytime terrestrial observing, where aperture does not rule to the same degree, and not for the same reason. (The guiding principle here seems to be envy of those presumed to know, rather than actual understanding. No wonder discussion gets nowhere.) This notion that you will see "better color" is particularly ridiculous, and the observations of people who can persuade themselves they see what they think is supposed to be true are simply not to be trusted. The same can be said of "more detail in deep shadows" unless the entire field is in shadow. "More detail" in general will be a very modest effect, and due to stopping down a larger objective, not using it at full aperture. But all this has been said already, to no apparent effect.Size Matters: The Case for Really Big Binoculars
Size Matters: A Case for Really Big Binoculars Contrary to what some of us would like to believe size really does matter. Flight, for example, imposes strict limits on size. Ostriches...www.audubon.org
A forum is at its best when people work together to sort something out, at its worst when they just keep citing whatever they can find online to support their (current) favorite argument. Dennis himself can go on forever and seems to enjoy that, but all necessary criticisms seem to have been made, so why is this thread continuing?
I agree. You are just saying it differently. You're right, a 10x40 is often times better in low light than a 7x35. Hunter's really like a 10x42 for that reason.
I find it humorous when somebody keeps telling me I can't be seeing something I am seeing. It is kind of like the people that see UFO's. I know what I saw, so all you're convincing me that I couldn't be seeing what I am seeing is not going to change my mind. You may not see it and that is fine, but I know what I saw, and I saw that a 8x56 will go deeper into shadows than an 8x42, and it also has fewer aberrations, is more transparent, has better CA control and has way less glare. All your baloney about how it couldn't be is not going to change my mind or make it untrue. Henry proved it objectively that an 8x56 is superior to an 8x42, but either his methods are beyond your comprehension or you don't believe him. I didn't believe it at first either until I started comparing 8x32 and 8x42 binoculars to an 8x56 and I realized they are better in many ways, and it is not just about brightness.
"Stopped down to 42mm: Things get interesting. Now, the 8x56 is clearly superior to the 8x42. Measured resolution is excellent for both, about 2.9 arc sec, but the 64x image looks better in the 8x56. It’s cleaner, with higher contrast and visibly less chromatic aberration. The star test shows improved correction for spherical aberration in the 8x56 to probably better than 1 wave. The improvements are explained by the change in focal ratio. The stopped down 8x56 is now operating at around f/4.5 instead of below f/3.5
Stopped down to 32mm: Both stopped down binoculars have about 3.9 arc sec resolution, and both show improvements in the 64x image quality. The 8x56 is better. Its 64x image now looks quite respectably clean and contrasty with very little chromatic aberration. Spherical aberration in the 8x56 improves to perhaps 1/2 wave. Now, its optics are operating at about f/5.8. The stopped down 8x42 is operating at about f/4.8.
Stopped down to 24mm: Now the 8x56 becomes quite a good f/7.5 telescope, almost a true APO with about 1/4 wave SA.
The point of all this is to show that the 8x56 really has no better (perhaps slightly worse) optics than the 8x42 when they are compared at full aperture, but when the 8x56 is stopped down to 42mm and below it shows significantly lower aberrations than the 8x42 (at the same aperture) simply because the 8x56 focal length is longer. If the 8x42 had the same focal length, it would certainly perform just as well.
Now, does any of this matter when you simply look through the binoculars at 8x? To my delight, the answer is yes. In daylight, he 8x56 FL produces the sharpest, cleanest and most transparent image I’ve yet seen in a binocular. It’s very obvious comparing it to other binoculars tripod mounted, but even hand holding I’m always aware that the image is unusually fine by binocular standards. I wouldn’t have expected any binocular to make the 8x42FL, Nikon 7x50 Prostar and 8x32SE look mushy and dull in sunlight, but the 8x56 FL does it.
Besides the reduced longitudinal CA and SA seen in star testing, there is also a reduction in lateral color that is quite obvious in daylight. Lateral color is probably almost always what people are seeing when they complain about “color fringing” in binoculars. There is also a modest but welcome increase in the size of the “sweet spot” compared to the 8x42FL. Less lateral color and a bigger sweet spot are two more benefits that come from the higher objective focal ratio, because the less steep light cone allows the eyepiece to perform better off-axis.
But, alas, edge of the field astigmatism is still this binocular’s weakest performance characteristic, just like the 8x42FL. The 7mm exit pupil also has a benefit in daylight. There is virtually complete freedom from “flare”. When bright reflections from the edge of the objective reach the eye they are out at the edge of a 7mm circle of light, so the flare tends to fall invisibly on the iris rather than entering the eye."
World's Best 8X42: The Zeiss 8X56FL
The image provided by the best current binoculars looks so good that it’s easy to fall into the assumption that binoculars are now so close to optical perfection that further improvement wouldn’t accomplish anything as it would be invisible to the eye. Every now and then I disabuse myself of...
www.birdforum.net
Paultricounty
Well-known member
But not as humorous as most of your posts. Again you don’t read what people are saying (maybe a vision thing) nobody is telling you , you don’t see what you see, we’re just saying what you see doesn’t exist in the optics, in other words what you see is because of your vision or lack thereof. it might be possible the larger objective are making up for other issues with the individual. You can’t deny (maybe you could) that if one person sees a small flying dog, but 50 other people looking at the object say it’s not a flying dog doesn’t mean, it’s a flying dog because you see it , maybe your on drugs. Now if you were to say you’ve seen a UFO, I would probably believe you did.
if we were to believe what you’re saying, and some of us don’t , Its not going to change your mind , but it is untrue wether you want to believe it or not.
It’s not about comprehension or that we don’t believe Henry , Its mostly clear that you cherry pick things that others say to push the nonsense , and leave the parts that don’t support your position out. They are not better in many ways under good lighting conditions than an equal quality 42.
Always end your statements with , in your opinion. Otherwise some new members (the veterans know it’s nonsense from experience) will think your stating some facts, and not something that is only effecting you as an individual.
Besides the reduced longitudinal CA and SA seen in star testing, there is also a reduction in lateral color that is quite obvious in daylight. Lateral color is probably almost always what people are seeing when they complain about “color fringing” in binoculars. There is also a modest but welcome increase in the size of the “sweet spot” compared to the 8x42FL. Less lateral color and a bigger sweet spot are two more benefits that come from the higher objective focal ratio, because the less steep light cone allows the eyepiece to perform better off-axis.
But, alas, edge of the field astigmatism is still this binocular’s weakest performance characteristic, just like the 8x42FL. The 7mm exit pupil also has a benefit in daylight. There is virtually complete freedom from “flare”. When bright reflections from the edge of the objective reach the eye they are out at the edge of a 7mm circle of light, so the flare tends to fall invisibly on the iris rather than entering the eye."
World's Best 8X42: The Zeiss 8X56FL
The image provided by the best current binoculars looks so good that it’s easy to fall into the assumption that binoculars are now so close to optical perfection that further improvement wouldn’t accomplish anything as it would be invisible to the eye. Every now and then I disabuse myself of...
Last edited:
tenex
reality-based
I should note that I don't tripod-mount binoculars for terrestrial observation; nor do I use doublers or triplers to examine them more critically; nor do I imagine most people on this forum do, including you.
As for skepticism of whatever you claim, you're the guy who just put a bin you never even heard of on your "glare resistant" recommendation list after merely scanning a generally positive review that doesn't even mention glare, on an internet blurb site whose reviews are always generally positive because the author (who sounds like a bot, or at least uses cut and paste heavily) makes money from clicks. (Glare Monsters!) That's a previously unimagined level of absurdity. So whatever you say you think you see has very little credibility... which you shouldn't really find humorous.
Last edited:
Paultricounty
Well-known member
This is my public service announcement to newcomers. BODD (beware of Denco disinformation) 🤣.
If this wasn’t so sad it would be hysterical. It’s almost like you’re talking about yourself, and 90% of the people on BF are saying about you.
As stated by nine out of ten people who respond to your post , this is mostly true only under low light conditions and not under 90% of observing conditions. I am out right now observing with four people ( whom by the way laugh at most of your posts) with the Leica 10 x 50 UV, 10x 42 UV and 10x42 Noctivids , under clear sun lit sky’s. The only difference , is due to the specific binoculars themselves and coatings. There doesn’t seem to be any benefit whatsoever under these conditions with the extra 8 mm of objective size.
Paultricounty
Well-known member
I’m adding to my post #130. We’re finishing up with out little observing session with the three Leica’s.
Of the Leica 10 x 50 UV, 10x 42 UV and 10x42 Noctivid, it was kind of unanimous of all four observers, the Noctivids were the brightest and sharpest of the three. There is on guy that called it a tossup with the 50UV and Noctivids (he’s 87 years old) maybe that’s telling us something. Both UV’s had a little better color saturation , but only when going back and forth between the three. We’re going to repeat this subjective exercise late this afternoon and at dusk. We’re going to be adding a 10x56 Conquest and a 10x32 EL.
Paul
Of the Leica 10 x 50 UV, 10x 42 UV and 10x42 Noctivid, it was kind of unanimous of all four observers, the Noctivids were the brightest and sharpest of the three. There is on guy that called it a tossup with the 50UV and Noctivids (he’s 87 years old) maybe that’s telling us something. Both UV’s had a little better color saturation , but only when going back and forth between the three. We’re going to repeat this subjective exercise late this afternoon and at dusk. We’re going to be adding a 10x56 Conquest and a 10x32 EL.
Paul
tenex
reality-based
When somebody doesn't pay attention to what others are saying, they waste everyone's time.
Oh, I believed it; I got an SLC 10x56. The problem is that you keep corrupting whatever Henry said by exaggeration, ignoring distinctions or subtleties, and worst of all, combining it indiscriminately with false and misleading claims from other sources.
The point you seem unwilling to grasp is that the differences are less obvious when not using a tripod, as hardly anyone here does.
I didn't say puff is a bot; I said the author of BBR reviews "sounds like a bot, or at least uses cut and paste heavily". You seem unable to distinguish the quality of sources, just scrounging for anything at all that seems to support your view of the moment (or perhaps that's your definition of quality?) and dismissing anything that doesn't -- including, until very recently, most anything Henry said (one wonders what changed there).
Such a peculiar combination of confidence and ignorance. (Bots constantly join Birdforum and post garbage, usually in Chinese. It turns up in the new posts list but the mods clean it up quickly.)
Last edited:
henry link
Well-known member
Hi tenex,
Thanks or putting things better in post 131 than I could have done. I've tried to stay out of this thread even though, alas, quotes from my 16 year old review seem to show up in most of Dennis's posts.
I really can't support either Dennis or Paul in their dispute. Since they haven't bothered to test their binoculars for aberrations, neither of them (nor the rest of Paul's crew) know what aberrations are present or in what amounts. So, we're getting the usual hurling back and forth of subjective impressions.
Thanks or putting things better in post 131 than I could have done. I've tried to stay out of this thread even though, alas, quotes from my 16 year old review seem to show up in most of Dennis's posts.
I really can't support either Dennis or Paul in their dispute. Since they haven't bothered to test their binoculars for aberrations, neither of them (nor the rest of Paul's crew) know what aberrations are present or in what amounts. So, we're getting the usual hurling back and forth of subjective impressions.
Paultricounty
Well-known member
Henry,
We were only looking for levels of brightness in good lighting conditions hand held, not much more. Maybe just looking for a little edge distortion and CA. As I stated in most of my replies to Dennis, it was just to dispute what was said about larger objective size in binoculars of similar quality under certain conditions, nothing more. It was totally subjective and I pointed that out a few times. The only reason Pauls crew was brought in , was to see for myself if it was just me or others subjectively observed the same result/subjective opinion.
Maybe if you didn't stay out of it until now, and corrected or had little input to what Dennis was saying and misquoting you ( I believe out of context) then we wouldn't have had to tolerate 132 posts on it. 🙏
Paul
We were only looking for levels of brightness in good lighting conditions hand held, not much more. Maybe just looking for a little edge distortion and CA. As I stated in most of my replies to Dennis, it was just to dispute what was said about larger objective size in binoculars of similar quality under certain conditions, nothing more. It was totally subjective and I pointed that out a few times. The only reason Pauls crew was brought in , was to see for myself if it was just me or others subjectively observed the same result/subjective opinion.
Maybe if you didn't stay out of it until now, and corrected or had little input to what Dennis was saying and misquoting you ( I believe out of context) then we wouldn't have had to tolerate 132 posts on it.
🙏Paul
Henry. Here is one of your old posts where you photographed the difference in a Habicht 8x30 and Zeiss 8x56 FL, stopped down to 22 mm to simulate bright daylight. It really shows what a difference a bigger aperture can make, even in daylight. The Zeiss 8x56 FL is obviously better. A lot of your posts like this are what made me try an 8x56, and I have come to agree with you. I have not photographed the difference, but subjectively I can easily see a difference in an 8x42 and an 8x56.
Victory HT 8x42
Hello, Visiting my son at London, after been with him at his PhD in Economics graduation in the EUI (European University Institute), Firenze, Italy, I made a visit at Harrods. Just to take a look at the place. As the last year, they have DEALS in binoculars. Two were VERY GOOD SALE offers...
www.birdforum.net
"Very interesting discussion, guys. I can’t add much, but some images I recently made through two binoculars might be relevant.
For the last week I’ve been working to try to improve my ability to accurately photograph the the true measured resolution of binoculars on a 1951 USAF resolution chart. By using a 600mm FL telescope behind the binocular eyepiece with the camera sensor at prime focus I’ve finally come pretty close. The images below (reduced in size to fit here) show the chart at 400” imaged through an 8x30 Swarovski Habicht (left) at full aperture and an 8x56 Zeiss FL stopped down to 30mm to match the aperture of the Habicht.
When looking directly through the binoculars, the smallest line pairs I can resolve with my 20/15 acuity are Group 0/ Element 6, and they look very tiny. If you can move back from your computer screen until you can barely resolve those line pairs in the Zeiss image, you will see something like what I see. If your acuity is 20/20 then back up until you can resolve Group 0/ Element 3 to see how the chart would appear to you and if, like David, you have super 20/10 acuity use Group 1/ element 3.
Even in these slightly degraded images, I think it’s obvious why the Zeiss image at normal magnification looks “sharper” and "cleaner" than the Swarovski image. Not only does the Zeiss resolve higher spatial frequencies than the Swarovski, frequencies beyond anyone’s eyesight acuity, but it also looks sharper and higher contrast even at the lowest spatial frequencies on the chart that are easily resolved by both binoculars. There is no trade-off here between low frequency contrast and high frequency resolution; the Zeiss is better at both, which is just what you would expect from an instrument with lower spherical and chromatic aberrations..
I also made images with both binoculars stopped down to 22mm to simulate bright daylight. Both show lower aberrations and reduced resolution when stopped down, but the Zeiss is still obviously better.
On the subject of pupil dilation in daylight, I tested my own today using a method I’ve described before in which a binocular refocused to infinity is used to examine a defocused artificial star at about 3m. Two pieces of black masking tape are stuck to the trim ring in front of the objectives to form an open slit between them. The width of the slit when it barely shows on both sides of the defocused star disk tells you how much of the objective lens diameter is entering the eye. For me, that was 18mm of the Swarovski Habicht objective (indicating a 2.25 mm eye pupil) when the artificial star (glitter point on a small shiny ball) was placed in bright sunlight. It increased to 24mm in open shade (pinhole in front of an LED light) and 28mm in deeper shade underneath a rhododendron. So, it’s obviously quite possible to use the full 30mm objective of an 8x30 in normal daylight, or probably even the full 42mm objective of an 8x42 on really dark days."
Attachments
Last edited:
hgalbraith1949
Well-known member
As with Henry, I certainly do not want to get enmeshed in this back and forth with Dennis and his detractors. Quite frankly I find it churlish and approaching venomous. Here is all that I know: a few days ago I took my 3 pairs of bins out into the field at sunrise and compared them by looking closely at savanna sparrows (for the non-yanks these are small highly streaked little brown birds) I spent maybe an hour looking at the same individuals with the objective of comparing results between the 3 instruments. The sun had not yet cleared the horizon and it was certainly low-light conditions.
The three instruments were NL 8x32s, SF 8x42s, and SF 10x32s. All of which I am very impressed with. How much difference in image brightness was there between the three? Not as much as I expected. The difference between the two 8-powers was there, but minimal and if I had not been conducting an experiment I might not have noticed at all. The difference between the 10-power and the 8s was a little more noticeable but not glaring or off-putting. The difference between the 32s and the 42s was small compared with the WEIGHT difference - 22oz vs 27oz. This is MUCH more important to me than the image brightness. A lot of my field work is usually carried out just before and after dawn and I find that I often grab the NLs on the way out the door, but it is the weight difference, not the brightness that determines it.
This is not a controlled scientific experiment because there are probably many other variables that remained uncontrolled (different coatings, prisms, etc). But FOR ME I saw little difference between the bins and I would happily use either of them in low light conditions. As in all of biology there may be a small statistically significant difference, but that may not mean that it is practically significant.
The three instruments were NL 8x32s, SF 8x42s, and SF 10x32s. All of which I am very impressed with. How much difference in image brightness was there between the three? Not as much as I expected. The difference between the two 8-powers was there, but minimal and if I had not been conducting an experiment I might not have noticed at all. The difference between the 10-power and the 8s was a little more noticeable but not glaring or off-putting. The difference between the 32s and the 42s was small compared with the WEIGHT difference - 22oz vs 27oz. This is MUCH more important to me than the image brightness. A lot of my field work is usually carried out just before and after dawn and I find that I often grab the NLs on the way out the door, but it is the weight difference, not the brightness that determines it.
This is not a controlled scientific experiment because there are probably many other variables that remained uncontrolled (different coatings, prisms, etc). But FOR ME I saw little difference between the bins and I would happily use either of them in low light conditions. As in all of biology there may be a small statistically significant difference, but that may not mean that it is practically significant.
Paultricounty
Well-known member
Thank you. That's exactly what Ive been saying from the beginning of the thread. And you were in a low light conditions and can barely notice a difference. In bright conditions these differences are even less.
There is not enough difference in aperture between the binoculars you compared to make a huge difference in brightness in low light. When you have very little light to begin with, you have to really amplify it to see anything. Throw an 8x56 SLC into the mix and you will see what I mean.
There is a BIG difference in low light performance between an 8x42 and an 8x56. An 8x56 gathers almost 2x the light that an 8x42 does. The 8x42 starts giving up when the sun goes down, but the 8x56 is like you turned the lights on. They are almost like they have built in illumination. You can see in pitch black places with an 8x56, almost like night vision.
You will see better in low light with an 8x56 than you can with your own eyes, which is not so with an 8x42. That huge 56 mm aperture makes a big difference in low light. That is why hunters that hunt in low light use an 8x56 like hog hunters.
If you look at the chart below, you will see how huge the difference is in Lux between Direct Sunlight, Ambient Daylight, Overcast Daylight and Sunset & Sunrise. When you only have 400 Lux to begin with as in Sunset & Sunrise you need to amplify it many times before you can see anything and a 32 mm and 42 mm aperture isn't big enough. Even on an overcast day you only have 1000 Lux and the much better light gathering of an 8x56 will help you see things.
| Natural Light Condition | Typical Lux |
|---|---|
| Direct Sunlight | 32,000 to 100,000 |
| Ambient Daylight | 10,000 to 25,000 |
| Overcast Daylight | 1000 |
| Sunset & Sunrise | 400 |
Last edited:
Paultricounty
Well-known member
No Dennis, many don't.
Thats what everybody has been saying for the whole discussion.
Conndomat
United States of Europe
@[email protected] and @Paultricounty
How about a supervision lesson? Tomorrow 3 p.m. in my practice?
The first therapy session is free, binoculars are not allowed... 😁
Andreas
How about a supervision lesson? Tomorrow 3 p.m. in my practice?
The first therapy session is free, binoculars are not allowed... 😁
Andreas
Paultricounty
Well-known member
Who's going to supervise you?Its way to rough over here in the binocular sub forum, Im going back to ruffled feathers on the Ukraine and Gaza discussions.
Paul
