Orion 2x54 ultra wide binoculars !?

[AntennaGuy]

Hi all. Has anybody tried these? And/or have you seen them offered under a different brand name?
https://www.telescope.com/Orion/Orion-2 ... 132268.uts
Note that the objectives are considerably larger than the Vixen or Kasai low-power ~2x ultra-wide binoculars.
Thanks!

Added: OK, I just saw these are pre-order, so not available yet... unless they are an Orion re-branding?

[Mandrew]

I have a pair on pre-order, and I will give a full review when I get them. I am a Binos-freak, and I can see a lot of different ways to use them.

[Lady Fraktor]

Vixen has sold a similar set for a few years now and there are other retailers that sell them as well.
One of our bino guys at AF had 2-3 different powered sets and enjoyed them.
He did post reviews of them there if you are feeling brave

[kt4hx]

Well they give a larger TFOV (36° vs 28°) and are less expensive ($150 vs $170) than the Kasai sold at Agena.

https://agenaastro.com/kasai-trading-wi ... -view.html

While you can see the Orion video presentation for them on their site, here is a link to it on youtube:



I think something like that would be quite interesting at our dark site for scanning along the Milky Way, as well as getting a nice overall presentation of the sky in the broader sense.

I don't know why, but this reminded me of about ten years ago when Orion was offering their "Monster Dobs" of 36, 40 and 50 inch models! That didn't seem to last too long, which is understandable given the prices! Here is a glimpse courtesy of the Wayback Machine:

http://web.archive.org/web/201002120604 ... telescopes

[stewe]

Thanks for sharing, these binoculars seem very interesting. Looking forward to reading the review by Mandrew.

[stewe]

I don't know why, but this reminded me of about ten years ago when Orion was offering their "Monster Dobs" of 36, 40 and 50 inch models! That didn't seem to last too long, which is understandable given the prices! Here is a glimpse courtesy of the Wayback Machine:

http://web.archive.org/web/201002120604 ... telescopes

Geez, 50-inch Dob, it's the first time I see this. Wondering if anyone bought one while they were on sale.
They write:
"If your passion is the deep-sky and you want the biggest Dob at the star party, this Monster Dobsonian makes everything else look puny."
Sure: bringing this grab-and-go scope to a star party should be a breeze..

[kt4hx]

I don't know why, but this reminded me of about ten years ago when Orion was offering their "Monster Dobs" of 36, 40 and 50 inch models! That didn't seem to last too long, which is understandable given the prices! Here is a glimpse courtesy of the Wayback Machine:

http://web.archive.org/web/201002120604 ... telescopes

Geez, 50-inch Dob, it's the first time I see this. Wondering if anyone bought one while they were on sale.
They write:
"If your passion is the deep-sky and you want the biggest Dob at the star party, this Monster Dobsonian makes everything else look puny."
Sure: bringing this grab-and-go scope to a star party should be a breeze..

I cannot verify if any were ever sold. They were not mass produced, rather would be built as ordered. Certainly at the cost, they wouldn't stock them. Below is an image of the 36 inch model that was displayed at the April 2010 NEAF event I believe. However, from what I read, the original 36 inch mirror shattered during the vacuum coating process and that structure contains a 24 inch mirror. It was only a display model anyway. Orion contracted the noted Canadian mirror producer Normand Fullum to produce the mirrors for any orders and from what I've read a 50 inch model had been ordered by some organization, but I cannot verify that. By sometime in 2011 I believe they were no longer seen on the Orion website. I guess it was someone's "big" idea that fell flat. While looking through such a large scope would be quite an interesting thing to do, the cost is extremely prohibitive. I also wouldn't like the aspect of having to stand up on a tall ladder to observe. I am 6 ft tall and with my 17.5 inch f/4.5 at most I have to stand on the bottom step of a step stool when at zenith.

[DeanD]

Back to the binos... Good try at highjacking the thread!
I have the Kasai versions, and I find them a bit of fun for scanning, and giving me a "darker-sky" experience from my urban sky. I am sure these Orions would do like-wise. However, the full field of view is only obtainable if you aren't wearing glasses: the closer you can get your eye to the eyepiece the better.
Given that the galilean-style optics produce an "exit pupil" that is effectively as wide or wider than the aperture of the eyepiece (in the case of the Kasai pair the eyepiece has an aperture of around 9mm), I am wondering what advantage a larger objective lens would provide? Whether they are 2.3x40 or 2x54 they still transmit way more light than your pupil can cope with (unless you are a whale or a giant squid...).
Can any optics experts out there enlighten me please?

- Dean

[stewe]

I am wondering what advantage a larger objective lens would provide? Whether they are 2.3x40 or 2x54 they still transmit way more light than your pupil can cope with (unless you are a whale or a giant squid...).
Can any optics experts out there enlighten me please?

I think the answer to your question is that larger objective lens diameter provides a larger true field of view.

[Max Nomad]

Hi all. Has anybody tried these? And/or have you seen them offered under a different brand name?
https://www.telescope.com/Orion/Orion-2 ... 132268.uts
Note that the objectives are considerably larger than the Vixen or Kasai low-power ~2x ultra-wide binoculars.
Thanks!

Added: OK, I just saw these are pre-order, so not available yet... unless they are an Orion re-branding?

I've got a similar set, Kasai Trading 2.3x40 Wide Field Binoculars with 28° True Field of View. They're interesting to play with but admittedly my time with them has been relatively limited. I found that light pollution and sky transparency/seeing conditions makes a big difference with them (I live within city limits under Bortle 7-8 skies). I keep them in my car along with an 8x56 Celestron Skymaster DX. If I happen to be somewhere under darker skies I'll pull over and use the two to do some impromptu stargazing.

[DeanD]

I am wondering what advantage a larger objective lens would provide? Whether they are 2.3x40 or 2x54 they still transmit way more light than your pupil can cope with (unless you are a whale or a giant squid...).
Can any optics experts out there enlighten me please?

I think the answer to your question is that larger objective lens diameter provides a larger true field of view.

Thanks Stewe. I note that they are 2x as opposed to the Kasai's 2.3x. This would provide a larger TFOV too (and in a similar amount that the larger objectives would seem to provide): so is it the magnification or the objective size that does this? Or maybe it is easier/cheaper to manufacture the larger objective to give a sharper image at the edge than the smaller one for the same magnification?

- Dean

[Ruud]

With a larger front lens an opera glass can give a wider view, but to see it in its entirety your own pupil has to be uncomfortably close to the eye lens:

Eye relief is zero and there is no exit pupil.

I have a small 4x22 pair of binoculars with positive eye lenses which actually have exit pupils. They may only show a 17° view, but they do so much more ergonomically than the negative eye lenses of opera glasses:

They cost around €25 and aren't bad at all. Eye relief is some 15mm and the exit pupil is 5.5mm. Kasai and many other brands have them. They are sharp on-axis and the sweet spot is about 50% of the view. The outer 10% of the field is a mess, but with 68º afov this is not much of a problem (for me). Closest focus is about 2.5m.

They look like this:

Kasau4x22.png (104 KiB) Viewed 10608 times

Mind that these aren't suited for people with widely spaced eyes. Ideal for children though, whose heads are often too small for other binoculars.

[stewe]

I am wondering what advantage a larger objective lens would provide? Whether they are 2.3x40 or 2x54 they still transmit way more light than your pupil can cope with (unless you are a whale or a giant squid...).
Can any optics experts out there enlighten me please?

I think the answer to your question is that larger objective lens diameter provides a larger true field of view.

Thanks Stewe. I note that they are 2x as opposed to the Kasai's 2.3x. This would provide a larger TFOV too (and in a similar amount that the larger objectives would seem to provide): so is it the magnification or the objective size that does this? Or maybe it is easier/cheaper to manufacture the larger objective to give a sharper image at the edge than the smaller one for the same magnification?

Since these binoculars have a Galilean design, the TFOV cannot be computed in the same way as you would for a Keplerian refractor. Also, exit pupil and eye relief are undefined for Galilean telescopes. Parallel entering rays exit parallel, and the image is virtual at infinity. You can perhaps imagine these optics like looking through a hole: the larger the hole and/or the closer you bring your eye, the larger the field becomes. Or at least this is my perception, but it was long ago since I learned about this kind of optics so I would not be surprised it someone would eventually correct/refine what I wrote. I am not sure what Orion mean by 72 deg apparent field of view. At which eye distance? And what I am really wondering about is whether the images produced by these binoculars have tolerable distortions and how messy they are off axis, i.e., how much one can really take advantage of the huge field of view.
Could anyone who own the Kasai or a similar model enlighten us?

[AntennaGuy]

... I am not sure what Orion mean by 72 deg apparent field of view. ...

Well, I have a pretty confident guess where that 72 deg number comes from! It comes from (drum roll please) adding up the 36 deg for each eye. Yes, that's a silly thing to do. People do silly things, sometimes. Especially people who prepare advertising literature. No offense intended, truly, to those silly people (although I would understand if they choose to take offense anyway...). Physics ain't easy, after all.
Alternatively: 36 deg True FOV = 72 deg Apparent FOV, at 2X magnification. So... maybe they meant that!! Added: Yes, on second thought, I think they did mean that. Carry on, then.

[stewe]

Well, I have a pretty confident guess where that 72 deg number comes from! It comes from (drum roll please) adding up the 36 deg for each eye. Yes, that's a silly thing to do. People do silly things, sometimes. Especially people who prepare advertising literature. No offense intended, truly, to those silly people (although I would understand if they choose to take offense anyway...). Physics ain't easy, after all.
Alternatively: 36 deg True FOV = 72 deg Apparent FOV, at 2X magnification. So... maybe they meant that!! Added: Yes, on second thought, I think they did mean that. Carry on, then.

Aha.. At which eye relief? At which eye pupil diameter?

[AntennaGuy]

Aha.. At which eye relief? At which eye pupil diameter?

With your eye as close as you can get it to the lens without actually forcing your eyelashes painfully backward, I suspect....
Not sure about how the pupil diameter will figure in, though. Let's see what folks with experience on similar binocs have to say.

[KingClinton]

Please note that in post #12 by Ruud the first two images posted are GIF's with a large size and will not auto play.
By clicking on the image it will open in a new window and animate.

This is a set forum function and we cannot change it, so please be sure to hover your mouse over a image to establish if it is a GIF or not, bit tedious but that's how the forum software works.

viewtopic.php?f=49&t=7253#p63778

[DeanD]

I think the answer to your question is that larger objective lens diameter provides a larger true field of view.

Thanks Stewe. I note that they are 2x as opposed to the Kasai's 2.3x. This would provide a larger TFOV too (and in a similar amount that the larger objectives would seem to provide): so is it the magnification or the objective size that does this? Or maybe it is easier/cheaper to manufacture the larger objective to give a sharper image at the edge than the smaller one for the same magnification?

Since these binoculars have a Galilean design, the TFOV cannot be computed in the same way as you would for a Keplerian refractor. Also, exit pupil and eye relief are undefined for Galilean telescopes. Parallel entering rays exit parallel, and the image is virtual at infinity. You can perhaps imagine these optics like looking through a hole: the larger the hole and/or the closer you bring your eye, the larger the field becomes. Or at least this is my perception, but it was long ago since I learned about this kind of optics so I would not be surprised it someone would eventually correct/refine what I wrote. I am not sure what Orion mean by 72 deg apparent field of view. At which eye distance? And what I am really wondering about is whether the images produced by these binoculars have tolerable distortions and how messy they are off axis, i.e., how much one can really take advantage of the huge field of view.
Could anyone who own the Kasai or a similar model enlighten us?

Looking through the Kasai's I can see from Rigel to Betelguese and a couple of degrees either side of them. This equates to a realistic TFOV of around 23-25 degrees. This is with my eyes almost touching the lens. As you get closer you can see more and the claimed figure of 28 degrees is probably pretty accurate if they are mashed right under your eye-brow ridges(!), but the edge of the field seems noticeably degraded: although if you move your eye around a bit (like when you are use a 100-degree eyepiece) things improve. I would estimate the "sweet spot" as around 75% of the FOV: which is actually pretty good. If you are wearing glasses then I suspect the FOV would be of the order of 15 degrees: it simply depends on how close you can get your eye to the lens.

Kasai claim that with their latest model (I have the first version) they have improved the view "dramatically" (see: http://www.kasai-trading.jp/widebino28neoexe.html ), and they also claim that stars are sharp across the whole field. I am not sure that this is really true for any binoculars, although my Tak 22x60's come pretty close...

Another problem of course is that if like me you have astigmatism then you need to wear your glasses to see sharp stars: but then you have a considerably reduced, (but sharper!) FOV.

Bottom line is that they do give a huge FOV and they give great views of huge objects, such as the central Milky Way. From the city they give you a couple of extra magnitudes and most constellations fit into the FOV, so (as I have noted previously) it is a bit like heading out into the country. In July in my favourite dark sky location (with SQM readings ranging from 21.6 at worst to 22.1 at best (Bortle 1)) and the centre of the Milky Way overhead (and casting shadows) the view is spectacular...

If you like sitting back in a "zero gravity" chair and simply scanning with binoculars they are a lot of fun.

- Dean

[Mandrew]

Update: I was notified by Orion that they would get these in around the end of March. I am pretty sure that the hold up is because of coronavirus delays.

[John Baars]

I own the 2,3 X 40 Kasai.
It is like Stewe and DeanD say in their posts.
Others told the truth about it too, they are Galilean bino's ( Holland type) and exit pupils are not calculated the same way as we are used to. The field of view depends of how close you can get with your eyes. Like already said above you can consider it as looking through a wide tube; the shorter the tube the wider the field looks. The edge is not the edge of your eyepieces' fieldlens, but the one of the objective.

One important point is that you can't look sideways in it, like we are used to in normal bino's. If you do so you will be punished with unsharp stars, colors and unpleasant collimation. You have to look straight forward in it. So you have to turn your head with the bino pressed to the eyes. Bit uneasy but you'll get used to it.

I use it for finding individual star-hopping stars in whole constellations under my LP skies. Stars that I don't see with the naked eye. Under dark skies the sight of the Milky Way is awesome!