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Where premium quality meets exceptional value. ZEISS Conquest HDX.

News from Zeiss - SFL 50 (2 Viewers)

ArchStanton said:
I noticed th the guy was wearing a size hat, so I’m wondering if he’s compensated in some way by Zeiss. However, he gave a pretty good rundown on the SFL 10x40 binoculars, and I liked how he gave his personal preference about eyecup adjustment. I don’t use eyeglasses while using binoculars and prefer the eyecups as far down as possible because I find less FOV is lost.
Click to expand...
Exactly, if you don't wear eyeglasses you can keep the eye cups all the way down and just hover your eyes over the oculars, and you can see the FOV right to the field stop. A lot of people do that, and it is pretty cool how big the FOV is.
 
Dennis Mau said:
Exactly, if you don't wear eyeglasses you can keep the eye cups all the way down and just hover your eyes over the oculars, and you can see the FOV right to the field stop. A lot of people do that, and it is pretty cool how big the FOV is.
Click to expand...
I don’t use the hovering technique because it’s not as steady but rest the binoculars right below my brow on the edge of my eye sockets. It worked pretty well with the Kowa Genesis 8x33’s that I tried, and the view was excellent. I had to adjust the Zeiss SFL 8x40’s one click up, and the FOV was still pretty large.
 
ArchStanton said:
I don’t use the hovering technique because it’s not as steady but rest the binoculars right below my brow on the edge of my eye sockets. It worked pretty well with the Kowa Genesis 8x33’s that I tried, and the view was excellent. I had to adjust the Zeiss SFL 8x40’s one click up, and the FOV was still pretty large.
Click to expand...
A guy at Sportsman's Warehouse showed me how to do that with the eye cups all the way down, and I was amazed at how big the FOV is.
 
Hermann said:
Interesting. 136 posts on binoculars that none of the guys posting here has seen yet. Lots of speculation, some of it pretty wild.
Click to expand...
Anticipation and speculation about SFL 50 are fine, but what generates hundreds of posts is random chat and reflexive reactions. Someone would be more interested in the 8x, I in the 12. They say a tripod is necessary to appreciate 12x, I say that's true of any binocular, what matters is that I see more detail with 12x than 10. They've said that before, I've said that before. (Actually I refrained this time; I don't want to have to change my name.) None of it really has to do with SFL 50, but on it goes...

Based on what Zeiss has said about the 50s, I'll be interested to see whether they're any improvement over the 30/40s regarding CA etc.
 
I come in very late to the party.
I was not aware of the SFL 50mm line up until literally half an hour ago...

I am definitely interested in how the SFL 12x50 will perform.
They have them in stock over here so I might pop in to town to have a look at it tomorrow. I have a few gaps in my work schedule. :)

The timing is impeccable. I sold my Leica 12x50 UVHD+ this weekend to a very nice guy.
Much as I enjoyed it, I came to the conclusion that my Meopta 12x50 serves me better for the very thing that I most use it for and I am very familiar with it.

Considering the price of the SFL 12x50 I am not sure if I would go as far as to replace the Meopta 12x50 - it would have to be a hell of a binocular to dethrone the Meopta.

But it will be interesting, considering it is a brand new model and I would like to see what they can do in this magnification.
I will bring the Meopta with me for the comparison. I have no expectations other than the SFL being lighter, probably having better eye relief and perhaps larger AFOV. All nice attributes but at that price point it had better be... ...better.
 
Vespobuteo said:
The 12x50 might make more sense vs 12x42 in really low light as you are down to a 3.5mm EP for the latter.
But you would need a tripod to appreciate the extra mag of a 12x, as seen in the YT video.

The question still is how these SFL 50:s perform in birding situations.
Birds on branches, in high contrast scenarios etc.
Click to expand...
This.
I have been quite happy with the performance of the SFL8x40 for high contrast scenarios and birds on branches.
The Meopta 12x does that even better though, and I am not quite sure the SFL 12x50 would reach that level if it resembles the SFL8x40 but with a higher magnification.

But,seeing is believing. Won't find out until I have seen it.

I am interested in seeing if the SFL 12x50 is easier to handhold than the Meopta 12x50. I am doing "ok" with the Meopta but use it mostly on a monopod. With the Leica UVHD12x50 I was pretty comfortable handholding it and preferred it over the Meopta for general use but for (especially high contrast) birds in flight I was more at ease with the Meopta, a combination of the focuser and the "clean" center image.

edit: the only 12x binocular I have been very comfortable handholding has been the Swaro NL12x42. For other reasons I still prefer the Meopta though.
 
Hello Dennis,

Thank you for contacting ZEISS. I have included some detailed information below regarding your topic:

The refraction or bending of light by a lens is primarily determined by the lens's curvature and the material's refractive index, rather than its thickness. However, lens thickness can play a role in the overall optical properties and performance of the lens.
  1. Curvature of the Lens Surfaces:
    • The degree to which a lens bends light is largely dependent on the curvature of its surfaces. A lens with more curved surfaces (higher curvature) will bend light more than a lens with flatter surfaces (lower curvature).
  2. Refractive Index of the Lens Material:
    • The refractive index (nn) of the material from which the lens is made also affects how much light is bent. A material with a higher refractive index will bend light more than a material with a lower refractive index.
  3. Lens Thickness:
    • While thickness itself does not directly determine the bending of light, it can influence the lens's overall optical power and aberrations. Thicker lenses may introduce more optical aberrations, such as spherical aberration, which can affect image quality.

Refraction and Lens Design:​

  • Thin Lenses: In the thin lens approximation, the thickness of the lens is considered negligible compared to the radii of curvature of its surfaces. The lens maker's equation for a thin lens is given by: 1f=(n−1)(1R1−1R2)f1=(n−1)(R11−R21) where:
    • ff is the focal length of the lens,
    • nn is the refractive index of the lens material,
    • R1R1 and R2R2 are the radii of curvature of the lens surfaces.
  • Thick Lenses: For thicker lenses, the lens maker's equation becomes more complex and takes into account the lens thickness (dd). The equation for a thick lens is: 1f=(n−1)[1R1−1R2+(n−1)dnR1R2]f1=(n−1)[R11−R21+nR1R2(n−1)d] where dd is the thickness of the lens along its optical axis.
In summary, a thicker lens does not inherently refract or bend light more than a thinner lens. The primary factors that determine the bending of light are the curvature of the lens surfaces and the refractive index of the lens material. Thickness can influence the overall optical performance and introduce aberrations, but it is not the main factor in determining the degree of light refraction.
If you have any more questions or need further clarification, feel free to ask!
Kind regards,
Cheryl
__________

Cheryl Sarli
Business Development

ZEISS Research Microscopy Solutions
One North Broadway
White Plains New York 10601
United States

Customer Service: +1 800 233-2343
[email protected]
[email protected]
www.zeiss.com/us/microscopy
 
Seems I've heard that somewhere before...

Actually I'd still nitpick the way this (nontechnical herself) person put it. "Thicker" lenses do not increase spherical aberration because they're thicker, but because they have greater curvature. They just end up thicker because of that.
 
tenex said:
"Thicker" lenses do not increase spherical aberration because they're thicker, but because they have greater curvature. They just end up thicker because of that.
Click to expand...
Exactly.

Still, this considers single lenses, not doublets, and certainly not complex designs.

Perhaps Dennis could ask about the objective focal ratios...
 
Dennis Mau said:
Hello Dennis,

Thank you for contacting ZEISS. I have included some detailed information below regarding your topic:

The refraction or bending of light by a lens is primarily determined by the lens's curvature and the material's refractive index, rather than its thickness. However, lens thickness can play a role in the overall optical properties and performance of the lens.
  1. Curvature of the Lens Surfaces:
    • The degree to which a lens bends light is largely dependent on the curvature of its surfaces. A lens with more curved surfaces (higher curvature) will bend light more than a lens with flatter surfaces (lower curvature).
  2. Refractive Index of the Lens Material:
    • The refractive index (nn) of the material from which the lens is made also affects how much light is bent. A material with a higher refractive index will bend light more than a material with a lower refractive index.
  3. Lens Thickness:
    • While thickness itself does not directly determine the bending of light, it can influence the lens's overall optical power and aberrations. Thicker lenses may introduce more optical aberrations, such as spherical aberration, which can affect image quality.

Refraction and Lens Design:​

  • Thin Lenses: In the thin lens approximation, the thickness of the lens is considered negligible compared to the radii of curvature of its surfaces. The lens maker's equation for a thin lens is given by: 1f=(n−1)(1R1−1R2)f1=(n−1)(R11−R21) where:
    • ff is the focal length of the lens,
    • nn is the refractive index of the lens material,
    • R1R1 and R2R2 are the radii of curvature of the lens surfaces.
  • Thick Lenses: For thicker lenses, the lens maker's equation becomes more complex and takes into account the lens thickness (dd). The equation for a thick lens is: 1f=(n−1)[1R1−1R2+(n−1)dnR1R2]f1=(n−1)[R11−R21+nR1R2(n−1)d] where dd is the thickness of the lens along its optical axis.
In summary, a thicker lens does not inherently refract or bend light more than a thinner lens. The primary factors that determine the bending of light are the curvature of the lens surfaces and the refractive index of the lens material. Thickness can influence the overall optical performance and introduce aberrations, but it is not the main factor in determining the degree of light refraction.
If you have any more questions or need further clarification, feel free to ask!
Kind regards,
Cheryl
__________

Cheryl Sarli
Business Development

ZEISS Research Microscopy Solutions
One North Broadway
White Plains New York 10601
United States

Customer Service: +1 800 233-2343
[email protected]
[email protected]
www.zeiss.com/us/microscopy
Click to expand...

This was generated by ChatGPT or a similar AI text generator.

Cheers,
Holger
 
Interesting that this explanation of optics was from someone at the Research Microscopy division at Zeiss. Their optics do a completely different job from binoculars.

I know optics work in basically the same way but I wonder what the explanation would be from someone in their Sports Optics division.
 
Sebzwo said:
The icing on the cake would be Zeiss using Abbe-König optical systems in the future again.
blogs.zeiss.com

Enhanced vision in the darkness - ZEISS Hunting

If maximum brightness is what you are looking for, the Abbe-Koenig prism is the best choice. Why? This system reverses the image without any loss of light.
blogs.zeiss.com
Click to expand...

Zeiss still do in the Victory RF line.

I suspect the SFL50 would be longer and heavier if they did use AK.
 

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