Is this possible? A hypothetical ultra wide angle binocular with compound eyes (1 Viewer)

[kimmik]

While not ever going to exist in real life, my brief back-of-the-envelope seems to make it a possible design even if it is difficult to optimise.

Combining 7 lenses in a mosaic, with each having their own prisms and 50degree-ish AFOV eyepiece, modified to be hexagonal and lined up nearly seamlessly, one could imagine an ultrawide view in a handheld binocular.

The easier option would be digital VR display, but that would require batteries (spoils my imagination!).

Another but currently existent option is to take a 100+ degree eyepiece and use a fast camera lens as the objective - has anyone tried this? e.g. 100degree 20mm eyepiece, 200mm f2.8, 10x with exit pupil of 7mm.

 

[Binastro]

The camera lens won't work as the eyepieces are too wide and the 200mm f/2.8 lens too fast for the eyepieces.
At least for a binocular.

There was the Koehler 120 degree eyepiece for submarine periscopes about 1943.

I have used monocular converters on a 300mm f/2.8 lens with reasonable results, even though the eyepieces should only work at f/4.
I do have 1.5x teleconverters that deliver better results, but very few camera lenses are up to the quality of good telescope optics.

Mirror lenses work well, but these are slow.

Regards,
B.

 

[kimmik]

I suspect the biggest issue with camera lens, is the light cones are usually divergent which limits the FOV with eyepieces. It is ok to diverge for camera sensors but will vignette heavily with an eyepiece.

Some hobby telescopes on cloudynights are f/3.3. They don't seem to post digiscope pictures though.

Edit: here's a compound eye camera with 10 gigapixel and 180degree vision. Not handheld! It uses a sphere as its primary lens, and then a large array of small telephoto lenses on small sensors which look like rod cells in the retina.

 

[Binastro]

Celestron fast telescopes are f/1.95

Also Celestron 300mm f/1.5.

1950s Baker-Nunn satellite tracking lenses were 20 inch aperture f/1.0. (Correction)
500mm f/1.0
Cost $200,000 in 1950s.

There are f/1.0 telescopes nowadays.

But these are imaging telescopes.

Hills cloud lens by Beck London 1920s 180 degrees.

I have used several f/2.8 camera lenses with 10mm eyepieces.

B.

 

[kimmik]

The nighthunting spider Dinopis Subrufus has main eyes with:

f/0.58
aperture - 1.325mm
focal length - 0.771mm
receptors - 20um
spherical abberation correction
180degree fov

 

[William Lewis]

Isn't that the one that basically renews most of its photo receptors at the back of its eye on a daily basis?

Insect biology is fascinating, the reason flies move out of the way of a deftly placed swat is there nervous system actually works faster then ours, they can perceive the swat coming, compute the danger and react to it by starting up there flight muscles in a fraction of a second.

The flight of insects is also really interesting, the protrusions immediately behind a crane fly's wings are actually sensors to detect air currents so they can adjust there flight accordingly. Also really small flies have to flap there winds faster than any neuron can fire to activate the muscle so they have a "click" mechanism so the wings flick from the up to down position without any specific nervous impulse, kind of like when a jar lid pops as you unscrew it as it releases the pressure.

Invertebrates have been refining these things for a lot longer than us new fangled back boned beings....

 

[Maljunulo]

The flight of insects is also really interesting, the protrusions immediately behind a crane fly's wings are actually sensors to detect air currents so they can adjust there flight accordingly.

Those are called “halteres” and it was my understanding that they are vestigial wings, which act as gyroscopes when they vibrate during flight.

I believe all Diptera have these, rather than the four wings of the Hymenoptera, etc.

 

[William Lewis]

Those are called “halteres” and it was my understanding that they are vestigial wings, which act as gyroscopes when they vibrate during flight.

I believe all Diptera have these, rather than the four wings of the Hymenoptera, etc.

That's the one! Yes there just more apparent on crane flies.

 

[kimmik]

Invertebrates have been refining these things for a lot longer than us new fangled back boned beings....

Amazing how miniaturised life can become and still maintain these precision functions. The human inner ear is pretty amazing but the simplicity of the haltere is fabulous and probably weighs less than a microgram and provides the same angular acceleration data for the brain to process.

For spider eyes, I've attached the full paper where I quoted from earlier, from 1977 so hopefully no concerns about copyright but happy to take down if issues from the forum.

After learning about spider vision, it is such a misnomer to call it "simple eyes" which sounds like they should be inferior to "compound eyes", but really these so called simple eyes are almost identical in anatomy to human eyes! Just tiny because they are in a spider the size of a pinhead!

Spider vision - Wikipedia

en.wikipedia.org

 

[Maljunulo]

Since Salticids can’t move their eyes or their “head” they can move their retina, in order to look in a slightly different direction.

When at the limit, they then have to move their entire body to look in a new direction.

 

[kimmik]

Since Salticids can’t move their eyes or their “head” they can move their retina, in order to look in a slightly different direction.

When at the limit, they then have to move their entire body to look in a new direction.

really cool, and they literally look like a pair of binoculars lol.

Primary eyes - zoomed cameras with sensor shift
Secondary eyes - wide angle 360 degrees

 

[etudiant]

really cool, and they literally look like a pair of binoculars lol.

Primary eyes - zoomed cameras with sensor shift
Secondary eyes - wide angle 360 degrees

View attachment 1474477View attachment 1474478

Insect vision has lots of surprising capabilities.
For instance, a dragon fly has eyes that cover well over 180*, both horizontally as well as vertically.
So some elements of their eye are always looking directly at the sun, with no apparent damage.
A good spot for a bit of research, imho.

 

[kimmik]

I briefly searched to no avail about how most insects and animals seem to be just fine looking at the sun, with their panoramic eyes, when humans must squint and look away when the sun is nearby.

Never thought about this before but there must be some adaptation that made it possible, to have no apparent injury when a point source 5 order of magnitude brighter than the rest is shining on ultrasensitive retina receptors. bizarre!

 

[tenex]

Never thought about this before but there must be some adaptation that made it possible, to have no apparent injury when a point source 5 order of magnitude brighter than the rest is shining on ultrasensitive retina receptors. bizarre!

Something must partly cover the retina or move it out of the way (as recently mentioned). Fascinating.

 

[kimmik]

I’ve just used a 100degree eyepiece with f/2.8 camera lens… OMG 😱 20mm and 80mm, making 4x monocular at 7mm exit pupil.

It is sharp bright and shows full field of view. No prism will be big enough to erect this beast unfortunately 😳 image circle is 40mm.

So to answer my own question: yes you can use f/2.8 camera lens with ultrawide astro eyepiece, some combinations allow distance focus but some combos cannot.

 

[has530]

I’ve just used a 100degree eyepiece with f/2.8 camera lens… OMG 😱 20mm and 80mm, making 4x monocular at 7mm exit pupil.

It is sharp bright and shows full field of view. No prism will be big enough to erect this beast unfortunately 😳 image circle is 40mm.

So to answer my own question: yes you can use f/2.8 camera lens with ultrawide astro eyepiece, some combinations allow distance focus but some combos cannot.

Very cool, I would love to give this a try. As for prisms, you certainly can get something big enough to erect it although I am unsure how you would assemble it all in a holdable form. Here is a right angle prism from thorlabs with over 40mm clear aperture and I have seen prisms over 300mm (not that that is practical). One could also go the "cheater" route and erect it with mirrors. I've seen some of the stuff you've mocked up and am sure you could sort it out!

 

[Binastro]

Last night encouraged by Kimmik's post I took my No Name 92 degree eyepiece.

It is 12.5mm focus, high quality, very nice coatings.

I got it as an one off special some time ago at a good price.

I unscrewed the very large front part, which is a 1.25 inch fit at the front.
The screw captive part might fit T2 or Celestron. I'll have to see.

There is a large focus part at the back of the eyepiece marked N to infinity with opposing arrows.
It has a wide range by helical.

I took at random from a box of lenses the Minolta 35mm f/2.8 35mm film camera lens.

With the eyepiece behind there may be room for a prism.

The resulting monocular is 2.8x12.5 with a 4.5mm exit pupil.

The image is very bright and covers about 33 degrees, which is probably much wider than the 2.1 or 2.3x40 or 42 Galilean binoculars.

There is mild pincushion distortion.

The view of the 35mm lens with eyepiece is inverted, but I must try it on say Orion, as the view might be very good.

I'll also look at what other lenses are in the box.

I have an Ethos, but don't like the view. It is just too large an angle for me and unpleasant to use.

Regards,
B.

 

[Canip]

I briefly searched to no avail about how most insects and animals seem to be just fine looking at the sun, with their panoramic eyes, when humans must squint and look away when the sun is nearby.

Never thought about this before but there must be some adaptation that made it possible, to have no apparent injury when a point source 5 order of magnitude brighter than the rest is shining on ultrasensitive retina receptors. bizarre!

Coming back to this old post, since we have now artificial intelligence doing all the research for us … 😆

This is what Chat GPT spits out when asked why insect eyes do not get damaged by direct exposure to the sun:

„Insects have compound eyes, which consist of thousands of individual lenses called ommatidia. Each ommatidium captures light and contributes to the overall image that the insect sees.

Unlike human eyes, which have a single lens that focuses light onto the retina, each ommatidium in an insect's compound eye has its own lens. This means that the light is spread out over many lenses, rather than concentrated on a single point like it is in the human eye.

Additionally, many insects have structures in their eyes that protect them from the harmful effects of sunlight. For example, some species of flies have a pigment called xanthommatin, which helps to filter out ultraviolet light. Some butterflies have pigment granules that help to scatter and absorb light, and some bees have hairs on their eyes that help to reduce the intensity of sunlight.

Therefore, while insects' eyes may be exposed to sunlight, they are able to handle it without damage due to their unique eye structure and protective features.“

True or not? I don‘t know, but it sounds relatively plausible 🧐

 

[wllmspd]

Given we’ve seen machine learning being fed basic information and coming up with new pharmaceuticals and working out how to make robots walk or play computer games from scratch. Could someone put an AI I front of a copy of zemax and leave it for a few months with some “simple” demands for wide angle, decent eye relief, flat field, sharp to the edge, stray light control, apo chromatic…. Usual suspects.. and see what it comes out with. Some consideration of manufacturability would be needed, but he fun to see what designs it imagined.

Peter

 

[Mono]

I can't see such a compound system coming to fruition without some computer mediation. After all we don't see with our eyes we see with our brains. Our mammalian brains are evolved to interpret the inputs from our mammalian eyes and turn them into what we see. No doubt insect brains have evolved to interpret inputs from their compound optical systems. The compound inputs would need to be fundamentally altered to mimic the inputs our mammalian brains expect.