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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Daytime benefit of large objectives? (1 Viewer)

I am inclined to get a 8x42 Zeiss SF but before I do, I will definitely check out that 8x56 or 10x56 SLC just because you sold me on that idea.

And may end up with one.
I think you would like the optics on any of those three. Get the Zeiss 8x42 SF for hiking and get a 56mm for low light and static use.
 
If you can wait, the price of the SF will come down, and buy the 8X56 SLC used, from a reputable dealer, you could save upwards of 1500.

Andy W.
 
If you can wait, the price of the SF will come down, and buy the 8X56 SLC used, from a reputable dealer, you could save upwards of 1500.

Andy W.

Andy ...... Curious as to why you think the price of the SF will be coming down? What time frame did you have in mind? Thanks.
 
Bruce, the price will come down as more used ones hit the market, as well as demos for less, (as soon as the box is opened, the price drops) folks also return them to the dealers, who have to sell them for less. I would say later this year.
My advice is that the SF is a nice glass from an optical perspective, and among other glass on the market are not worth 2700.00.

Andy W.
 
Bruce, the price will come down as more used ones hit the market, as well as demos for less, (as soon as the box is opened, the price drops) folks also return them to the dealers, who have to sell them for less. I would say later this year.
My advice is that the SF is a nice glass from an optical perspective, and among other glass on the market are not worth 2700.00.

Andy W.

Your guess is a good as mine on where the prices will go. I do not see anything coming up in the shorter term, from now to BirdFair in August, to think there will be any big changes. Longer term, if Swaro were to come out with an all new EL SV replacement, then that may have an impact depending on the pricing.

The grey SF first start hitting the streets in the fall and winter of 2014 and the blacks sometime after Birdfair in August 2016. That has been awhile to stabilize the used market, at least for the shorter term.

The price can have some material fluctuations during the short term. This is the result of short term promotions for new units and for some individuals highly motivated for a quick sale on the used side. Anyone willing to watch for a few months will likely come across a good deal.

Zeiss currently has an instant 10% off program on the SF. Optics Planet was offering a brand new black 8X42 SF for $2,308 the other day with the addition of their own 10% off discount. It was even less at Sports Optics but the status was back order when I saw it.

$2,300 is a lot of money but then I see lots of folks now just birding with DSLR cameras and big lenses costing $5,000 to $10,000 or even more. One guy had two big lens camera systems that I saw a couple of weeks ago. I feel like a relative pauper around them with my close out grey model. ;) Also keep in mind that binoculars do not have near the depreciation as electronic products such as digital cameras.

Probably the best deal on as SF can be on a grey model. They are the same optically as the black. The later production grey units has the same focus mechanism tolerances as the black units and Zeiss will furnish the new eye cups for free. Some closed out for under $1,700.

I agree with what you say in regards to the large objectivize 56mm Swaro SLC that have only been imported by Swaro USA for a couple of months or so. (The exception is the 15X56 which has always been available.) It may take some waiting to catch a used 8X56 on the market. Probably the best bet is to privately contact a forum sponsoring vendor to see if they are allowed to sell at a special member price compared to the minimum advertised price.
 
Tell me about older 10x50 SLC WB (Pre-Swarovision) circa 2007. What are its specs, most importantly, diopters at infinity value?

The older Swarovski 10x50 SLC, the later ones are very good, and will
give you a wow view.

These are among the best 10x50 binoculars available, in the top 5 even
with newer models offered in todays market.

I would like others to offer comparisons.

Jerry
 
The eye is poor at judging luminance, not the least, because the diameter of the pupil of the eye constantly oscillates (hippus) causing a 20% change in light levels at the retina every second or two.

When I've been in very bright light, like sun on snow, and then come into dimmer light quickly, I actually notice my vision flickering in brightness, though possibly more than 20% and definitely faster, more like a couple of times a second. Is this related to hippus?
 
If you can wait, the price of the SF will come down, and buy the 8X56 SLC used, from a reputable dealer, you could save upwards of 1500.

Andy W.
You can't really find the new model 8x56 SLC used yet. It just came into the US just lately and there isn't any on the used market yet. It is probably not a huge volume binocular either like an 8x42. I had to pay retail for mine from Eurooptics which was $2150.00. Then once people use them and see how good they are they won't sell them.;) I haven't seen much price drop on the SF either especially the black model. It is holding firmly in that alpha +$2500.00 range. I did see a LNIB black Zeiss SF 8x42 go for about $1750.00 on Ebay a few months ago. I threw a bid in but was outbid.
 
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NB. not that it's really necessary to cite anyone else in support of what I have stressed is my personal opinion, but at least one fairly experienced birder appears to have found the same; http://www.audubon.org/news/size-matters-case-really-big-binoculars

That piece is remarkably similar to the longer and even more "authoritative" Simpson/BetterView article I read years ago, and based my faulty understanding of larger apertures on. It says things like this:
A basic and immutable law of optics is that, all other things being equal, (magnification, quality, engineering, etc.) bigger objective lenses will give you a brighter, more satisfying view than smaller lenses. They will yield more detail and better color rendition than you can possibly obtain from smaller objectives. Big objective lenses allow you to see more detail in deep shadows.

It was precisely to question and investigate widespread claims like this, which I believed for years, that I began this thread. Immutable laws of optics? More like immutable misunderstandings of optics. Birding experience is one thing, knowledge of physics another.

That said, I do love the view of my 10x56 SLC even if I can't cite immutable reasons why. It's a keeper. Far better than the older SLC he's wearing in that article, too... makes you wonder whether believing is seeing.
 
Bruce,

Well for me, I am in no rush for the SF, (for me well over a couple of years away), just a suggestion to ETC - be it far fetched. One can always get some thing cheaper somewhere if one keeps his/her eyes out.
I have seen the cameras, yes the prices are out of this world, saw a Leica set up in the field the other day, work related, there must have been at least 50K worth of equipment and still more was being unloaded.

Dennis, what about Europe, are not the 8X50+ glass popular there.

Andy W.
 
Bruce,

Well for me, I am in no rush for the SF, (for me well over a couple of years away), just a suggestion to ETC - be it far fetched. One can always get some thing cheaper somewhere if one keeps his/her eyes out.
I have seen the cameras, yes the prices are out of this world, saw a Leica set up in the field the other day, work related, there must have been at least 50K worth of equipment and still more was being unloaded.

Dennis, what about Europe, are not the 8X50+ glass popular there.

Andy W.
You really can't get the Swarovski 8x56 SLC much cheaper overseas. I checked that out. Then you have a LOT of shipping costs and Swarovski will warranty them but they give you a little static.
 
That piece is remarkably similar to the longer and even more "authoritative" Simpson/BetterView article I read years ago, and based my faulty understanding of larger apertures on. It says things like this:
A basic and immutable law of optics is that, all other things being equal, (magnification, quality, engineering, etc.) bigger objective lenses will give you a brighter, more satisfying view than smaller lenses. They will yield more detail and better color rendition than you can possibly obtain from smaller objectives. Big objective lenses allow you to see more detail in deep shadows.

It was precisely to question and investigate widespread claims like this, which I believed for years, that I began this thread. Immutable laws of optics? More like immutable misunderstandings of optics. Birding experience is one thing, knowledge of physics another.

That said, I do love the view of my 10x56 SLC even if I can't cite immutable reasons why. It's a keeper. Far better than the older SLC he's wearing in that article, too... makes you wonder whether believing is seeing.
I love the view through my Swarovski 8x56 SLC also. It is the best view I have ever had through any binocular and I have had a lot of the best binoculars including the 8.5x42 SV and the 10x50 SV. If it is not due to the bigger aperture I don't know what else it is outside of maybe coating differences on the SLC to maximize contrast. This SLC is the most aberration free binocular I have ever looked through. The 8x56 SLC makes me want to try 8x42 SLC. After trying the 8x56 SLC I am beginning to think the SLC line are a good bargain compared to the EL.
 
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I love the view through my Swarovski 8x56 SLC also. It is the best view I have ever had through any binocular and I have had a lot of the best binoculars including the 8.5x42 SV and the 10x50 SV. If it is not due to the bigger aperture I don't know what else it is outside of maybe coating differences on the SLC to maximize contrast. This SLC is the most aberration free binocular I have ever looked through. The 8x56 SLC makes me want to try 8x42 SLC. After trying the 8x56 SLC I am beginning to think the SLC line are a good bargain compared to the EL.
Man up and get a real view...
https://www.adorama.com/nk1870sp.html
 
When I've been in very bright light, like sun on snow, and then come into dimmer light quickly, I actually notice my vision flickering in brightness, though possibly more than 20% and definitely faster, more like a couple of times a second. Is this related to hippus?

Obviously I don't know the precise level of light change you are refering to, but the difference between indoor and out door light levels might well be over 10 fold. The iris dilates more slowly than it contracts and it will usually take a few seconds to adjust. If it is very bright outside there will also be physiological changes in the retina which will take somewhat longer to readjust. Both will cause problems with over or underexposure which could well include flickering. This is quite different to hippus. If you just stare at a constantly lit scene, the diameter of your iris will constantly fluctuate with a variable frequency. This typically causes a 20-70% swing in light levels at the retina which will go totally unnoticed.

Hippus is on top of the normal responses to change large changes in light level which are also fairly rapid. If you were looking at a bright scene from a shaded spot, in the time taken to look down and pick up another binocular your pupil could have doubled in size, and then need to contract again when you look up.

I'm suggesting that no one would notice a 2 or 3% change in binocular transmission in normal use, if there wasn't a concurrent change in the colour balance as well. The eye is quite remarkable adapting to more than a billion fold range in light levels. It's just not so good at detecting the little changes.

David
 
I have read in the introductions to a couple of studies that the hippus phenomenon ceases or is suppressed by elevated levels of alertness and/or mental activity.

Lee
 
I have read in the introductions to a couple of studies that the hippus phenomenon ceases or is suppressed by elevated levels of alertness and/or mental activity.

Lee

That's true, and you would include other factors like time of day, age, medication and disease. The take home message is that, even though there are fairly large swings in retinal light flux and it's there pretty much all the time, you can't tell it's happening.

David
 
That piece is remarkably similar to the longer and even more "authoritative" Simpson/BetterView article I read years ago, and based my faulty understanding of larger apertures on. It says things like this:
A basic and immutable law of optics is that, all other things being equal, (magnification, quality, engineering, etc.) bigger objective lenses will give you a brighter, more satisfying view than smaller lenses. They will yield more detail and better color rendition than you can possibly obtain from smaller objectives. Big objective lenses allow you to see more detail in deep shadows.

It was precisely to question and investigate widespread claims like this, which I believed for years, that I began this thread. Immutable laws of optics? More like immutable misunderstandings of optics. Birding experience is one thing, knowledge of physics another.

That said, I do love the view of my 10x56 SLC even if I can't cite immutable reasons why. It's a keeper. Far better than the older SLC he's wearing in that article, too... makes you wonder whether believing is seeing.

I think those articles are examples of people seeing something they like, but not not understanding why. I do tend to a agree with the Audubon author that areas of deep shadow in daylight often do look more vivid and detailed in large exit pupil binoculars compared to small ones. I think that's because the eye is often dilated to an unexpectedly large aperture when viewing through binoculars in daylight. I've measured my pupil dilation (using the defocused artificial star method) at various levels of daylight with a binocular in front of my eyes and was surprised to find that deep shadow areas cause a dilation of close to 4mm even on sunny days and around 5mm on cloudy days.

Another effect that tends to make the overall FOV appear a little brighter in large exit pupil binoculars compared to small ones in bright daylight conditions is that a vignetted off-axis 7mm exit pupil has a larger surface area than an equally vignetted 4mm exit pupil. Typically, the minor axis of an almond shaped vignetted 7mm exit pupil in the outer parts of the FOV will still be wider than the diameter of the eye's pupil in bright light, allowing the eye to admit all the light it can, even close to the edge of the field. The minor axis of that same amount of vignetting from a 4mm exit pupil will likely be smaller than the diameter of the eye pupil and cause some gradual dimming of the image in the outer half of the field compared to the 7mm exit pupil.
 
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