Just ordered two matched 12" DSO mirrors for a binocular telescope

[Omaroo]

After being physically stunned by the images I saw at Lostock from Mark Suchting's dual-12" binocular telescope design, I have just gotten off the phone from him after ordering two of his matched DSO 12" f/5 mirrors. I can't wait to start co-designing the motor-driven co-collimated mirror cells and truss system with him. Mark has some very exciting ideas that we will no doubt spend hours discussing over the next few weeks. He will be building a dual 14" unit and hopes to be able to bring it to the South Pacific star party coming up. I hope that more people take the time to look through one of these units - as they have changed my view of the starts dramatically.

If you have made your own set of bino's - maybe you wouldn't mind imparting me some advice? There are so many designs that have been successfully built, it's staggering..... !

What a fun project this is going to be :)

[h0ughy]

your a glutton, your wife told me you already had 5 scopes. Drought breaking soon. they were nice weren't they????

[Omaroo]

Drought???

They were amazing, huh! You had a good look through them at Lostock? Just having a whole 12" scope for each eye is somewhat lavish - but well worth the asking price I think.

[erick]

I haven't got one scope yet, but from what I've read on bi-newts, I know I want one of these! Well, you just gotta dream the big dream! ;)

[Ric]

Hi Chris, that sounds like one awesome setup, you'll have to keep us posted with progress details and pictures.

Hi Houghy, the rain is coming for this setup, it's started in Qld with cyclones and floods and will slowly work it's way down as Chris nears completion. :lol:

Cheers :)

[iceman]

Wow Chris, straight in the deep end! Top Stuff!

The view was indeed spectacular! I can't wait to look thru the 14"'ers at SPSP.

[Omaroo]

Absolutely Ric :) It's going to POUR!!!!!!!!!!!!

I'm currently trolling through a bunch of designs from all over the place. A few nice examples to consider.......

[Omaroo]

You and me both Mike! :)

[sheeny]

Sweet dreams are made of these...

hmmm I saw them at Lostock but didn't have a look through them:rolleyes: .

Sounds like a great project!:thumbsup:

Al.

[Darkplague]

Some nice scopes there!

So to change the pupil distance on these scopes, you have to slew the UTA ring around to where you need it, is this how it is done?

Looking at that last picture, its looks to be quite a pain to move those rings with all those bolts holding them but I am only guessing.

The only drawback that I can see is that if you have to refocus anything, this will also affect your pupil distances, therefore requiring you to move those top rings, possilbly putting it slightly out of collimation each time :shrug:

[Omaroo]

Hi Mark :)

On the design that Mark brought to Lostock, the upper rings are mounted on teflon pads and are kept in place longitudinally by keeper roller bearings (see photo). A handle on each lets the observer just rotate them as they require. In situations like Lostock - where lots of different people look through them over a session - these are a boon. Rotating them does slightly affect collimation, but there are adjusters that are easily reached from the front to trim the mirrors on the fly. I suppose that the picture you refer to shows a scope that is more-or-less set for that individual.

Cheers
Chris

[sejanus]

hey, newbie question here.

Does 2 x 12" in the bi config, it is like looking through a 24" scope in terms of light gathering? do you get a bi more of a 3d look as it's using both eyes?

I've never used "bi" except in binoculars ;)

[gaa_ian]

It is an Awesome Experience !
I spent a few hours with Mark, setting up & looking through this scope.
While it does not have the light gathering ability of say the 25" obsession that was there for the Camp, the views were in some respects equally satisfying !

[Omaroo]

Given comparative mirror surface areas, you will obviously still gather more light from a single 24" over a dual 12", (452 sq. in vs 225 sq. in) so resolving power, perse, is still superior using a larger mirror (not that two 12" mirrors should be considered "small"). Even though more light is hitting your EP, images still appear as a flat object. The binocular projects a seemingly 3-dimensional image onto a viewing plane several inches in front of your face. I mentioned to Mark that through his friends' scope I visualise globular clusters now in a multi-dimensional vista, where individual stars almost look "spherical". You have a perception of "depth" that you've never seen until you look through one. It's quite incredible.

A 24" dob requires a substantial platform from which to view objects at or near zenith. I'm not in favour of ladders in the dark. The bino system, at f/5 means that at zenith your eyepieces are about natural eye-height from the ground. Viewing is just sooooo comfortable because you look down into the unit - rather than crane your neck skywards.

The other thing: I'd find it much easier with a dual 12" setup to lug around in a car than a 24"......

If you want to see a great bino website go here: http://www.binoscope.co.nz - it's a ripper site.

Cheers
Chris

[Omaroo]

Ah-ha! The only other bloke in earshot of my first view through a bino scope! G'Day Ian! :)

[Striker]

What a great project Omaroo.

Really look forward seeing the final result.

Good luck with it all.

[Starkler]

Silly question time.

We all would be aware that the subjects viewed are too far away to yield any kind of true stereoscopic vision, so what advantages does a binocular telescope give over a standard one fitted with a binoviewer?

[Ric]

Hi Chris, I haven't seen any mention of imaging through this setup. The fellow on the website you linked didnt mention it either.
I am assuming that you can but was wondering is there any advantage.

If you ever set it up at Cooma please let me know, I would quite happily walk there for a look. :D

Cheers

[sejanus]

thanks chris, sounds neat. keep us updated with how you go.

[Omaroo]

Starkler - In a word (as per the NZ site) a "feeling" is what you get. Although you won't get a true stereoscopic view in the proper sense because, as you say - objects are just too far away to get any real separation), just the fact that your two eyes are receiving data leads to a sense of depth - and moreso than viewing through just a bino attached to a monocular scope. I'm frustrated that I don't have, and can't give you a plausible technical explanation as to why it's so - Mark has a good grasp on a technical level how it works differently - and I invite him to post a response to this question here. Nebulous regions such as M42 and NGC2070 just have far more contrast for some reason - especially with twin OIII's on. As per all of the sites that rattle on about the virtues of bino vision - owners all universally have trouble putting the "it" into words.:shrug: It's just one of those things you have to see. SPSP will be the go if you can make it!

[Omaroo]

Rick - they'll be fabulous in Cooma. I'll let you know when they're coming down. It'll still be some months off... I have to build them first :)

[erick]

You'll need a pretty big "garden shed" for that fourth design! :scared:

[Omaroo]

Ah! The Mt Graham "LBT"! Yep - it'd be quite a "shed"!

[gaa_ian]

Good to hear you are taking the plunge Chris, i am sure you will not be sorry !

[Omaroo]

Thanks Ian :)

It's going to be quite a challenge I think - but you and I both agree that the visual result is pretty special.

Cheers!
Chris

[Satchmo]

( Apologies for all ensuing typos here folks !)

Geoff, I've covered this question a few times on various forums but its a very natural one.

For all interested heres a brief run-down on the advantages. The bi-newt effect is not about looking for parallax geberated 3D.
The brain somehow doesn't get fully fooled by beamsplitting device, when it comes to using th eadavatages of binocular vision. . I have compared extensively a true 8" binocular and a 12" with binoviewer, and I find that many of the brains image processing capabilities ( most particularly looking at fainter objects ) do not cut in as well with a beamsplitter. To get the 40% contrast increase afforded by binocular vison, you need a randomly varying signal to each eye. The brain also seems to do more processing when looking through two seperate cores of the atmosphere, than just splitting the same image to each eye.

The contrast enhancing effect in a true Bi-Newt is something obvious, which I don't see so definitevly in a beamsplitter. There is a moment when you first look into the eyepieces where your brain gathers the information. In the course of half a second or so, you suddenly see the background sky which is normally noisy and speckly, turn velvet black and seem to drop off into infinity, leaving the object in stark contrast. Seeing the Horsehead easily without filters was a good example of this. The moment when you first look into the eyepieces and this enhanced visual contrast cuts in is a kind of moment of intuition that you are getting all that is possible that I never tire of. The views of globular star clusters are other -wordly becasue your brain does not make `boiling porridge ' of the view whilst it searches for pattern amongst the threshold stars that come and go. The binocular view makes it 20% more likely that you will glimpse and confirm a threshold star in each eye and youtr brain will fix it in view for you. My first view of Omega Centauri through a 20" binocular confronted me with an object I had apparently never seen before as my eyes weaved down through 3 dimensional voids amongst red giant stars.

Bi-Newts are not so much about pseudo-stereoscopic affects , although they are very pleasant, and some find them very powerful and attractive.. An effect called `chromatic stereopsis' makes red stars look closer than blue ones.

http://www.binoscope.co.nz/3d.htm

This can give globular and open star clusters a very 3 dimensional look. What I find pleasurable with a well adjusted pair , is the impression that I am looking through a spaceship porthole..the window edge beeing fairly close and the view being much further in the distance. I call this `presence'.

A true binocular also shows you more sky area than an equivelent mococular, about 4 times more sky area in fact. Take into account that we are limited to about F4.5 ( for most peoples taste ) regardless of aperture, and the equivelent monocular ( seeing a similar thing by sheer aperture rather than contrast ) is about 40% larger aperture for low light level subjects. Given that a binoviewer on a Newt needs a 1.2X to 1.4X barlow to reach focus and it is of much longer focal length anyway, as rule of thumb you can achieve 4 X more sky area in a single view with an equivelent binocular Newtonian.

There are also issues with cumulative errors inside binoviewers and spherical aberration in them when passing faster light cones through prisms.

There is no doubt that bi-Newts are a very specialised Item. For the majority of people , a larger aperture monocular will always be the easier and preferred option. There has been a little evolution going on lately with Dave Moorehous's 2 Bi-Newts and now Pauls 12". We are sticking to the same basic design and trying to improve on it without getting off track each time. I think we are getting to the heart of a design that can be easily tackled by anyone with a one truss Dob allready under their belts, or at least a methodical approach.

Hopefully we can have a pair at the SPSP for people to look through and experience some of these.

I'd like to add that I applaud the explosion in the market of availability of quality Binoviewers, they are a compact and neat solution to access binocular viewing and the more access to the simple humanity of using both eyes to explore the Universe the better :)

Mark

[Omaroo]

Thanks Mark! Good explanation. :thumbsup:

[ving]

v/sweet chris :D
keep us updated :)

never looked thru one of these b4!

[Omaroo]

David - are you coming to SPSP? Mark will hopefully have a 14" set there. I'm not even sure I'll take any of my own scopes.:whistle: Then again - I daren't look through these as mine are going to be 12's...... :doh:

[skies2clear]

That's fantastic Chris. I can't personally think of a better project to embark on. It's great to see when people build there own stuff. The way Mark described his Bino experiences really captures the imagination, don't you think? Sort of sends you floating off into space somewhere.....

One of these days I would love to look through some, but no one around these parts I know has anything like that.

I had intended to build a bigger scope somewhere around 20", but now you guys have me thinking!

Good luck with the project.

Clear skies!

[Satchmo]

Hi Mark...Oh yea of little faith !!!!! :lol:

The top ends need only rotate a few mm or so between different observers. The thin ply lining of the cages extend down into the support plate that the cages mount on. The cutouts are lined with ebony star formica, with a rub of dry silicon grease. With your hands on either edge of the slewing bar, you can reach up with fingertips to the two cage handles and adjust the IPD spacing..it is smooth as a babies ***.

Yes the focus can upset the inter-ocular spacing slightly , so here is the drill.

Focus each eye coarsly.
Set your IPD distance by rotating the cages.
Fine/final focus each eye , which usually only means a tweak of a few 1/10s of a mm , which doesn't noticeably effect the IPD spacing
Enjoy the view

This is a routine that becomes completely automatic .
If a slight tweak is needed to the merging of images there are two big knobs under the eyepieces to do that..one becomes accustomed to doing that if needed without even being aware.

The new observer quickly learns ( driven by completely selfish motives ! ) to tweak the view to perfection. We found at Lostock that 4 people is about a good number to get through objects in a reasonable time , taking into account the slightly longer time for people to make their own adjustments. One thing still needed is an auto- electric shock on the eyepieces that can be set to so many minutes. I hardly remeber anyone willingly giving up the view to the next observer without a prompt :whistle:

[Omaroo]

:D

[skies2clear]

I read somewhere this can enhance your vision and permanently double your IQ...a bit like the Krell brain boost! :lol:

CS

[Digby]

Hello Chris,
Iam the owner of the 12'' binoscope you spent the weekend looking thru.
Iam glad to hear you intend to build your own. It sounds as if your on the
right track, in your research on the binoscope. There would be no better
person in australia I feel, than Mark to get you over the finish line.
I wish you all the best, and will be watching with interest.

Regards,
Paul:)

[Omaroo]

Paul - so you're the culprit! :D

Thanks so much for having Mark bring it to Lostock. I can only hope that whatever I build can be as nearly as effective as what you've put together. I can't wait to start specifying the parts, and having the base and mirror cell angling mechatronics on the drawing board. I'm so glad to have Mark and yourself to ask all the right questions of (as long as you don't mind, that is!). Are you coming to SPSP?

I'll keep in touch. If you're up to it, we'll get you out to nice and dark skies down at our club (Macarthur Astro Society) observing site at Belanglo State Forest or out at The Oaks one night soon. I 'd love to share the experience with fellow club members.

Cheers
Chris

[Digby]

Hi Chris,
Iam thinking about the SPSP.My partner is a cooma girl, so who knows, a vist down your way may one day be on the cards?
Regards,
Paul

[Omaroo]

A Cooma girl? :) Bring her back down any time....

We live in southern Sydney, but go down to our place down there every couple of weeks. It's a great place to view the skies from, as you'd know.

If you manage to come to SPSP I'd really enjoy meeting you and having a really good yak about some of the design aspects of your scope over a couple of good reds....

Cheers
Chris

[Digby]

Hi Chris,
A good incentive to attend the SPSP.

Regards,
Paul