space walk

[Piero]

One of the selling points of ultra wide angle (uwa) eyepieces is the so called space walk effect (sometimes also referred to as immersion).  

I think it would be interesting to hear from members who experienced this:

- What do you feel on a "space walk" using uwa eyepieces? 

- What do you suspect the causes are for the above feelings? (e.g. very distant field stop, image clarity, colour rendition, contrast, .... ?)

[Bart]

Hello

for me it's the field of view. You're looking at space all around the object you're viewing, lots of it. And, generally, they're very good quality eyepieces. Someone said it's as if the eyepiece 'gets out of the way' and leaves you with the view, and I agree. 

Barry

[iPeace]

Spacewalking is just getting lost up there, not being able or wanting to recognize or analyze, looking out through the window of your spacecraft, or even through the visor on the helmet of your spacesuit. More than looking, it's experiencing and it's better than 'virtual reality' because it is actually the old-fashioned kind of reality... I'm becoming something of a widefield junkie at the moment, as low-power, wide-angle surfing is what I find myself doing on clear nights.

At the risk of overreaching due to lack of experience and knowledge, here goes:

Televue 41mm Panoptic: widest actual field I can get, with very nice contrast and clarity.

Televue 31mm Nagler Type 5: more immersive due to the wider apparent field and with only a slightly narrower true field than the Panoptic, the extra magnification enhances the magic. More of the periferal vision effect.

Televue 21mm Ethos: smaller true field still, but also more magnification and more importantly, the window of your spacecraft is more of a bubble. Even more immersion. Even more magic.

I guess it's the sensation of the eyepiece taking you out there, and seemingly disappearing itself.

If you haven't tried it, you should.

[Tzitzis]

Dude, I used a UWA 100 I think a month or so ago. I saw the double cluster and it was.... WOW. So many stars and I was slewing the scope and it was like travelling in space... It was awesome... Black baground, so many stars.. If there was zooming it would be like a freaking trip....

GET ONE

[John]

I enjoy the feeling you get when the eyepiece / scope / etc just seems to "get out of the way" and its just you and the Universe. Eyepieces with wide fields of view can help but also I think a lot is down to the state of mind of the observer. I find this effect seems to happen when I've been concentrating hard on a particular class of object, usually something in the deep sky such as planetary nebulae or small galaxies. After a while I sort of get "in the groove" so to speak and find myself moving from target to target almost without thinking. It does not happen that often to be honest but its a wonderful feeling of intimacy with, old, immense and far off objects and the vastness of space which is difficult to describe to someone who has not experienced it. 

One particular pairing that can trigger this effect for me is the magnificent globular cluster M13 in Hercules and the small galaxy NGC 6207. These both lie in the same 1 degree field of view but their huge difference in distance and size can create an interesting sensation of immense perspective at times 

 

[Richard Hather]

I have to be honest because I sketch my observations I find myself getting immersed even with my plossl.

I can easily spend 1-2 hours observing one object trying to get every little detail I can if that isn't immersion I don't know what is.

But I do understand the allure of the spacewalk feeling, for me I just want crisp views regardless of fov.

Richard

[iPeace]

I agree with John and Richard, immersion is definitely influenced by state of mind. Puts the questions from the OP in an interesting perspective.

And, as I have implied, I do get the spacewalk experience with apparent fields of view below 100°. I would have to try Televue's 'big plossl', recently featured elsewhere here on SGL, to say whether I get it at 50° as well.

[Piero]

Thanks to all, very interesting comments.

I have to say that I never experienced a space walk feeling with my Naglers T6, although this might likely be due to the fact that touching the lens with my eye is something which easily distracts me.

In the last few evenings on DSOs and last night on the Moon I felt nicely lost in space. Despite the fact that there was a large amount of glass between the Moon and me, I dare to say that it was as if there weren't any glass at all. Just this white and contrast rich target in all its purity, floating in front of me and surrounded by intense black depth. No, I wasn't in my garden, I wasn't in front of my eyepiece and my telescope. I was out there in that gentle night, in the middle of this eternal silence, observing a perfect beauty.

[Size9Hex]

My first 3 or 4 months stargazing were purely with binoculars which have about a 50 degree apparent view. Facing directly up into space with both eyes open was very immersive. When I first got the scope (with 50 degree EPs), the view knocked my socks off, but it wasn't immersive. Instead of facing up into space, when I stepped back from the EP, I was facing the lawn, or garden fence, or wall of the house. And with the scope, I wasn't even able to use all my eyes...! It put me right back onto the ground. Hard to describe, but compared to the binos, it was like looking at galaxies through a microscope. Not at all immersive, same field of view as the binos, but different ergonomics, and one eye only.

Moving from the 50 degree stock eyepieces to 82s helped. I guess partly the bigger view itself and partly that you spend more time viewing and less time nudging the scope which helps you get into the groove (as nicely put by John). The low power eyepieces also seem more immersive than the high power, and I think this comes down again to spending less time nudging the scope and more time viewing.

In my opinion the "spacewalk" term is marketing nonsense though. I've never felt anything that profound. They're eyepieces. Excellent ones for sure (and I absolutely love mine), and more immersive than a non wide angle, but you're still just looking through an eyepiece with your hand over your other eye.

The only time I've ever felt lost in space was staring directly up at the summer Milky Way at the end of a dark site trip after packing my scope away. 180 degree field of view, staring straight at the zenith, couldn't see the ground, and all sense of up and down had gone. Absolute magic.

For more immersion, a couple of wide angles slotted into a binoviewer is tempting...

[Piero]

Well, I do see the marketing purpose in the spacewalk term, but I have also experienced it.

To me, ultra wide field eyepieces are not sufficient though. It's rather a combination of ultra wide field view, extremely limited (or none) light scatter, excellent contrast, no colour alteration, and extremely limited (or none) on axis distortion. To me if one observes through a pile of optics with the above features in a comfortable manner (with sufficient eye relief), with a good eyecup to protect the eye from external stray light, under a good steady sky, AND finally with a relaxed state of mind, spacewalking can be experienced and it's a lovely experience I have to say.

Piero

[Roy Challen]

Try naked eye viewing under a truly dark sky, say Bortle 1 or 2 - no eyepiece even comes close.

That's immersion.

Anything else is like comparing CRT televisions to wide screen TVs, wait till you go to an imax!

[Timebandit]

Hello. I feel that the spacewalk experience is a combination of many factors. You obviously have your mark one eyeballs which on  a dark clear night that can give you the ultimate wide field experience with points of light coming from all directions and so may that the sky's seem alive.

But your eyes are limited to the magnification of the light they can pick up and see , you then have the next type of spacewalk experience with binoculars which are quick and easy to use and having mark one eyeballs gives a great freedom to wandering around the sky's with a turn of your head . With the two eye's you are drawn into the surroundings of the dark sky's with the extra added points of lights which you cannot see with the naked eye. It surprising sometimes just how much more of the universe can be picked up with low power  binoculars versus the naked eye under dark sky's.

You obviously then have the telescope to add to the spacewalk experience, with a reasonable aperture telescope and quality eyepieces then to me a telescope is the ultimate spacewalk experience that a backyard enthusiast can achieve . Some people seem to take the glass between your eyes and the sky's as a negative. I think you should take it as a positive as without these Optical enhancers then we would be missing out on vast amount of detail in our universe. By being able to see close ups  on many planets, galaxy's, star clusters (which are a beautiful sight to see under a wide field reasonable magnification eyepiece in a telescope) then our eyes and minds would not have the privilege or pleasure of wandering around our sky's and space with such visual and mind enhancers. We are very lucky that we have access to scopes and eyepieces that allows us to stand in our dark sites or backyards and see so depths of space without having to rely on large observatory or photos from books. So a few pieces of glass should be seen as a positive addition to allowing us home amateur astronomer to see things that a generation or so ago could only dream about. When we look through our scope we are traveling back in time and in essence time travelling through time and space, as most of the item targets in space we look at, their light has started off from their destination to reach us before we were born and many points of lights are thousands and even millions of years old and much much older . The universe is full of discovery and through light speed we are able to see it's beautiful vision and expand our minds and knowledge. This is the spacewalk experience IMO seeing from where we have come to where we have arrived and space and time in the universe can be explored with the mark one eyeballs together with the high quality amateur equipment that is available to us today.☺      

[Roy Challen]

24 minutes ago, Timebandit said:

Hello. I feel that the spacewalk experience is a combination of many factors. You obviously have your mark one eyeballs which on  a dark clear night that can give you the ultimate wide field experience with points of light coming from all directions and so may that the sky's seem alive.

But your eyes are limited to the magnification of the light they can pick up and see , you then have the next type of spacewalk experience with binoculars which are quick and easy to use and having mark one eyeballs gives a great freedom to wandering around the sky's with a turn of your head . With the two eye's you are drawn into the surroundings of the dark sky's with the extra added points of lights which you cannot see with the naked eye. It surprising sometimes just how much more of the universe can be picked up with low power  binoculars versus the naked eye under dark sky's.

You obviously then have the telescope to add to the spacewalk experience, with a reasonable aperture telescope and quality eyepieces then to me a telescope is the ultimate spacewalk experience that a backyard enthusiast can achieve . Some people seem to take the glass between your eyes and the sky's as a negative. I think you should take it as a positive as without these Optical enhancers then we would be missing out on vast amount of detail in our universe. By being able to see close ups  on many planets, galaxy's, star clusters (which are a beautiful sight to see under a wide field reasonable magnification eyepiece in a telescope) then our eyes and minds would not have the privilege or pleasure of wandering around our sky's and space with such visual and mind enhancers. We are very lucky that we have access to scopes and eyepieces that allows us to stand in our dark sites or backyards and see so depths of space without having to rely on large observatory or photos from books. So a few pieces of glass should be seen as a positive addition to allowing us home amateur astronomer to see things that a generation or so ago could only dream about. When we look through our scope we are traveling back in time and in essence time travelling through time and space, as most of the item targets in space we look at, their light has started off from their destination to reach us before we were born and many points of lights are thousands and even millions of years old and much much older . The universe is full of discovery and through light speed we are able to see it's beautiful vision and expand our minds and knowledge. This is the spacewalk experience IMO seeing from where we have come to where we have arrived and space and time in the universe can be explored with the mark one eyeballs together with the high quality amateur equipment that is available to us today.☺      

I agree with what you say, and I don't consider optical aid as a negative, but as we are talking about the 'spacewalk' effect of wide field EPs I just think that the widest field is given by the naked eye with the horizon as the field stop. Narrowing the field through the use of optics can only diminish the effect (imo).

I have used 82 degree eyepieces, and certainly compared to my orthos they are wider, but not necessarily more immersive.

I guess we all have different ways of expressing immersion in our subjects.

[jetstream]

If you want to maximize the view of starfields in a telescope Hyperwides go a long way in helping. Used in conjunction with a telescope of complimenting design, 100deg EP's give a jaw dropping experience. Many have preferences in this experience, mine is using the 10" and 15" with the 21E on starfields- the explosion of bright stars emanating from the eyepiece is something to behold using the wide TFOV of the Hyperwide and no FS in the view.

Nagler describes this as majesty factor and Mel shows hows this works

 

		Aperture Field (60 deg eyepiece) Stars Field (100 deg eyepiece) Stars eye (7mm) 60 deg 1300 100 deg 3600 50mm 8 deg 2500 14 deg 6900 4 inch 4 deg 2700 6 deg 7600 8 inch 2 deg 2800 3.4 deg 7800 16 inch 1.1 deg 2700 1.8 deg 7600 32 inch 0.5 deg 2200 0.9 deg 6200
		This is from Bartels article in this link http://bbastrodesigns.com/rft.html

[Pig]

As john mentioned above the eyepiece simply disappears and dependant upon the target, should you look at say something like the double cluster or a spiral cluster you get like an inward taper effect when you hone in on a centre star, this can then be reversed and followed outward again. In addition the Ethos also show each individual star colour that emphasizes this effect ( I am not sure if the colours are as vibrant with big Dob but its great with my refractors )

[YKSE]

On ‎2016‎-‎08‎-‎13 at 17:59, Piero said:

One of the selling points of ultra wide angle (uwa) eyepieces is the so called space walk effect (sometimes also referred to as immersion).  

I think it would be interesting to hear from members who experienced this:

- What do you feel on a "space walk" using uwa eyepieces? 

- What do you suspect the causes are for the above feelings? (e.g. very distant field stop, image clarity, colour rendition, contrast, .... ?)

"space walk" was practical in everyone's mouth when they first looked through a T1 Naglers, nowadays with loads of eyepieces having UWA or extreme wide Angle(XWA)  in market, the word is not often mentioned when someone does a review of an UWA eyepiece, I wonder why?

I have used eyepiece wider than Naglers, can't say that I feel a bit of this space walk effect, yes, it's wider field of view than 70°, thats's it. Other characters for an eyepiece, such as good constrast, transmission, ergonomy(weight, size, ER, viewing comfort, etc) are more important than wider FOV for me, and these characters are not patented by UWA or XWA eyepieces.

The immersion I have felt in astronomy is using a simple pair of bins scanning Milky Way in dark sites. there're litterally open clusters in the whole FOV, dense-packed with millions of millions stars, no view through a single ocular beats that.

On ‎2016‎-‎08‎-‎14 at 20:38, Pig said:

As john mentioned above the eyepiece simply disappears and dependant upon the target, should you look at say something like the double cluster or a spiral cluster you get like an inward taper effect when you hone in on a centre star, this can then be reversed and followed outward again.

I believe that is the effect of pincushion distortion in many wide field eyepieces, where stars moving through the FOV in  arcs instead of straight lines

[John]

The feeling that I was referring to in my post was really an emotional response rather than an anlysis of this or that aberration or optical effect

I used to get it when using my old 60mm F/13 refractor with a home made eyepiece made from an old binocular eyepiece. It was a simple kellner type design with no field stop so the visual effect was like looking into a boundless pool of stars. I'm sure there were optical aberrations of many sorts on show but it was immense fun and I'm sure was responsible for me getting hooked on wider fields of view

A preference that has cost me a small fortune over the 35+ years since I used that DIY eyepiece

I might grow up one day !

[iPeace]

4 hours ago, John said:

I might grow up one day !

Don't.

[Rick Towns]

"Back in my day..." (says every grumpy old man you've ever met) when we couldn't afford a Nagler, the best we could do to get a lot of glass was a big Plössl. I have an Orion 50mm, but I never got the "space walk" sensation from it - although it gives a lot of actual sky, it is still limited to an apparent 50° field and the sky background never seems that dark to me.

Years later, I wound up buying an Antares Speers Waler 29mm eyepiece that had about 70° apparent field of view. That was the first time I said "Wow!" when looking at a star field. It wasn't a bad little eyepiece (sorry, it was rather BIG!), but the stars were pretty mushy in the outer 30% of the FOV. Still, it was the first to give me that sensation.

Similarly, one of my favourite things is to load up a high power eyepiece (say a 6mm Ortho) into my scope and find the Moon's limb... then shut off my RA drive. The Moon slowly glides through my eyepiece and because of the smaller FOV (~40° with my Ortho), I feel like I'm looking out the portal on a spaceship that is in orbit above the Moon. I sit in fascination until the terminator swings by, then I reset for another pass. THAT is how I like to roll (fly? walk? I dunno).

[Timebandit]

26 minutes ago, Rick Towns said:

"Back in my day..." (says every grumpy old man you've ever met) when we couldn't afford a Nagler, the best we could do to get a lot of glass was a big Plössl. I have an Orion 50mm, but I never got the "space walk" sensation from it - although it gives a lot of actual sky, it is still limited to an apparent 50° field and the sky background never seems that dark to me.

Years later, I wound up buying an Antares Speers Waler 29mm eyepiece that had about 70° apparent field of view. That was the first time I said "Wow!" when looking at a star field. It wasn't a bad little eyepiece (sorry, it was rather BIG!), but the stars were pretty mushy in the outer 30% of the FOV. Still, it was the first to give me that sensation.

Similarly, one of my favourite things is to load up a high power eyepiece (say a 6mm Ortho) into my scope and find the Moon's limb... then shut off my RA drive. The Moon slowly glides through my eyepiece and because of the smaller FOV (~40° with my Ortho), I feel like I'm looking out the portal on a spaceship that is in orbit above the Moon. I sit in fascination until the terminator swings by, then I reset for another pass. THAT is how I like to roll (fly? walk? I dunno).

 

Hello. I have very recently got into binoviewing. And the 120apo with binoviewers attached just takes lunar spacewalk to another level. With the two eye's on the scope not only do you seem to pick out more details on the lunar surface, but it is a far more relaxed way of viewing and the overall field of view just seem so vast. And due to the fact both eyes are immerse in the details of the moon you are completely shut off from the outside world, to a point you feel you are space walking on the moon.

I highly recommend binoviewing if you want to immerse yourself on a space walk of the lunar surface. Just a beautiful experience☺

[FenlandPaul]

Great thread, Piero, and some really interesting answers.  As you know, I've only got the limited ownership of one very battered but optically fine Type 1 Nagler 7mm to draw on. But when I first used this a few weeks ago it completely transformed my impression of M13, an object I've viewed countless times in different instruments over the last 24 years of observing. The wide but detailed field gave a view so rich with interest that I could have stared at this old favourite for hours had nextdoor's silver birch not got in the way. Was it "immersive"? Yes. What made it immersive? For me, it was a view that somehow quietened the soul, allowing myself to be still as the majesty of the universe glided slowly past my eyes with unfathomable grace and a sense of being unstoppable. It was the opportunity to forget that I was looking through an instrument and instead to feel that I was part of a wider cosmos. It was a great eye piece that simply allowed the sky to do the talking. As John says, the eyepiece "gets out of the way".

[Piero]

17 minutes ago, FenlandPaul said:

Great thread, Piero, and some really interesting answers.  As you know, I've only got the limited ownership of one very battered but optically fine Type 1 Nagler 7mm to draw on. But when I first used this a few weeks ago it completely transformed my impression of M13, an object I've viewed countless times in different instruments over the last 24 years of observing. The wide but detailed field gave a view so rich with interest that I could have stared at this old favourite for hours had nextdoor's silver birch not got in the way. Was it "immersive"? Yes. What made it immersive? For me, it was a view that somehow quietened the soul, allowing myself to be still as the majesty of the universe glided slowly past my eyes with unfathomable grace and a sense of being unstoppable. It was the opportunity to forget that I was looking through an instrument and instead to feel that I was part of a wider cosmos. It was a great eye piece that simply allowed the sky to do the talking. As John says, the eyepiece "gets out of the way".

I agree with you Paul! I have a very similar feeling and a good eye relief helps me quite a lot to relax my eye.

[Rick Towns]

3 hours ago, Timebandit said:

Hello. I have very recently got into binoviewing. And the 120apo with binoviewers attached just takes lunar spacewalk to another level. With the two eye's on the scope not only do you seem to pick out more details on the lunar surface, but it is a far more relaxed way of viewing and the overall field of view just seem so vast. And due to the fact both eyes are immerse in the details of the moon you are completely shut off from the outside world, to a point you feel you are space walking on the moon.

I highly recommend binoviewing if you want to immerse yourself on a space walk of the lunar surface. Just a beautiful experience☺

Interesting that you mention that (binoviewing) - in my closet I do have a William Optics binoviewer that I never use. I tried to get it to work with my 4" APO many years ago, and short of adding a big extension tube to the focuser, it was a "no-go".

But now I have an 8" SCT which has a HUGE focus range - I should dig it out and take a trip to the Moon! Thank you for the inspiration!

 

[michael.h.f.wilkinson]

My first SWA was a 40mm TMB Paragon, with 68 deg FOV. Very much more immersive than the 36mm Plossl I had before. The Meade S5K 14mm UWA was next up, and seeing the entire moon at 145x magnification was indeed like looking through the portal of the Apollo Command Module, some 2,650 km (1,645 miles) from the moon. I now have quite a collection of UWA and SWA EPs, and much prefer them to narrower ones. Space walk may be stretching things, but you get more sky in the FOV, which adds to immersion, and even if a 50mm Plossl gives (roughly) the same amount of sky as a 31mm Nagler, the latter gives much darker backgrounds.

[Piero]

Just now, michael.h.f.wilkinson said:

The Meade S5K 14mm UWA was next up, and seeing the entire moon at 145x magnification was indeed like looking through the portal of the Apollo Command Module, some 2,650 km (1,645 miles) from the moon.

I never really thought about the approximated distance due to magnification as you did.