SF 32 mm (1 Viewer)

Troubador said:

Thanks to Perseid on the 'Anyone else at American Bird Expo?' thread for posting this:

"I asked when we could expect a 32mm SF, and Mr. Ingraham said we might see them around next August; he also indicated that there would be some design tweaks in the new 32mm design based on experience gained from the original 42mm models (but he also said these tweaks would likely be minor and go unnoticed by many folks)".​

This strongly suggests SF 32 may be launched at next year's British Birdwatching Fair.

Lee

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Chosun Juan said:

Which means we might actually see them commonly available in the marketplace free from defects and quality and component material supply problems, oooh ..... I'd say, sometime north of 2020 ...... :smoke:

Now the CFRP Ultra FL x32 HT's could be out next year ...... iffinif Zeiss knew what it was doin' :cat:

Chosun :gh:

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Troubador said:

Thanks to Perseid on the 'Anyone else at American Bird Expo?' thread for posting this:

"I asked when we could expect a 32mm SF, and Mr. Ingraham said we might see them around next August; he also indicated that there would be some design tweaks in the new 32mm design based on experience gained from the original 42mm models (but he also said these tweaks would likely be minor and go unnoticed by many folks)".​

This strongly suggests SF 32 may be launched at next year's British Birdwatching Fair.

Lee

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FrankD said:

Would a 480 foot field of view interest anyone?

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ceasar said:

Frank,
It is going to cost a lot to design a 16mm eye piece with about a 9.2º field and give it comfortable eye relief. While we are talking about costs is this a good time to ask if it will also have a flat field?
Bob

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HighNorth said:

Erfle-style eyepieces like the one in the SF have good eye relief, and a flat field is a given I think, as the 8x and 10x SF also have it.

HN

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ceasar said:

I don't think that Swarovski is going to give away the secret of how they managed to put an eyepiece with a wide, flat field and 20mm of ER into their 8x32 Swarovision except to say that they designed it that way.

What ever they did wasn't cheap to accomplish.

Bob

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SuperDuty said:

This was posted some time back by a fellow from Swarovski. I don't know exactly what is meant.

Paramount to the ease of view of a pair of binoculars is the size of the edge bundle (Randpupille), a metric/property that I cannot ever remember having seen mentioned or explored on BirdForum. Naturally, the other factors, like the exit pupil diameter and eyecup shape, mentioned above, will also influence how easy it is to find the image. Said optical viewing comfort is obviously not a completely independent parameter and - for example - the easiest way to increase the field of view of our binoculars would be to sacrifice some of the edge bundle. This makes for a great improvement of the technical data sheet and impressive to look through, but would come at a very real cost to viewing comfort.
__________________
Dale Forbes

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SuperDuty said:

This was posted some time back by a fellow from Swarovski. I don't know exactly what is meant.

Paramount to the ease of view of a pair of binoculars is the size of the edge bundle (Randpupille), a metric/property that I cannot ever remember having seen mentioned or explored on BirdForum. Naturally, the other factors, like the exit pupil diameter and eyecup shape, mentioned above, will also influence how easy it is to find the image. Said optical viewing comfort is obviously not a completely independent parameter and - for example - the easiest way to increase the field of view of our binoculars would be to sacrifice some of the edge bundle. This makes for a great improvement of the technical data sheet and impressive to look through, but would come at a very real cost to viewing comfort.
__________________
Dale Forbes

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henry link said:

I'm pretty sure this "Randpupille" quote is about vignetting of the exit pupil at the edge of the field, which has been explored several times here. I've written a few times, for instance, on the subject of using defocused star points to directly observe the extent to which off-axis exit pupils are vignetted in different binoculars.

The fact is no binocular maintains the same fully round exit pupil of the field center all the way the field edge. Internal apertures, usually associated with the prisms, turn the round exit pupil bundle into a cat's eye shape bundle that increasingly narrows toward the edge. I believe binocular designers have long considered the area of the cat's eye at the edge to be visually harmless as long as its area is al least 50% of the area of the full exit pupil in the center. If more field width is imposed by increasing the diameter of the eyepiece field stop without increasing the size of the prisms that will reduce the area of the cat's eye at the edge to less than 50%, which would visibly darken the field edge and make pupil positioning more critical for avoiding edge blackouts.

Even without considering the added weight and size there's a limit to how large binocular prisms can be made because the light path through the prisms has to be short enough to fit between the back the objective and the eyepiece field stop. In small binoculars with internal focusing lenses there is simply not enough space for really big prisms.

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