31 replies to this topic

[faackanders2]

I did some comparisons with my setups, they both have their good points but for my favourite target, the Moon, the binoscope won out…… however I have now moved to more modest setups and am using a single refractor with binoviewer again….

WOW

[faackanders2]

For clarity, these are binoscopes: http://www.aokswiss....sicht_90fl.html

and these are BTs: https://www.apm-tele...binoculars-82mm

The former are binoscopes that could be split into telescopes (but why would you want to after going through the effort to collimate them).

The latter are large binoculars, which can't be split.

[Sarkikos]

Find from an owner if the achromat has enough in focus to accomdate the binoviewer.  Otherwise you will have to cut the tube, or use a barlow, which will limit low power viewing.

... or use a linear binoviewer which doesn't require a Barlow or OCS.

 

Mike

[A Y]

Let me recommend something from left-field: an easy and cheap way to try out binoscoping before buying a 2nd copy of a refractor is to build the Analog Sky Magic. It's a 3D printed 50mm binoscope, and you don't need a 3D printer to build it: I ordered the 3D printed parts (which also come in a format that's friendly for print services). Total cost of the entire instrument is between $500 and $1k all-in depending on what options you choose,

 

The Magic itself has great features to help alleviate common bino issues: collimation of the two sides is easy to do in the field in real time as you observe, and it's easy to use 2-inch filters with its magnetic cartridges which hold standard filters: I have a pair of DGM NPB filters that I use regularly. Its huge exit pupil means you get bright views even with filters. It even has a built-in alignable laser pointer so it's easy to find objects.

 

It's made from a pair of achromatic 50mm doublets in either f/3.7 or f/4.4 form and a pair of 50mm secondary mirrors. You order both things off AliExpress. And in case you associate 3D printing with low quality or cheap, you have to see the density of the baffling and razor teeth in the light path that can only be made economically with 3D printing: I think it's prioritizing important aspects of image quality in the tradition of John Dobson.

 

As the mirror size implies, it takes 2-inch eyepieces for the widest possible views and biggest exit pupils. I commonly use 24mm UFFs and 12mm Delos on mine, but I also have pairs of 30mm UFFs, 17.5 Morpheus, 6mm Delos, and soon 4.5mm Delos. The view is very satisfying especially considering how easy it is to transport and setup: I have mine on a small video tripod. I also have a Tak FS-102, SW 100ED and 150ED in my collection, but the Magic is my preferred winter observing instrument right now. I'll probably break out the big refractors again when planet season comes around.

 

If you'd like a longer focal length at the same aperture, Analog Sky just introduced the Sunny/Ember pair. I'm in the process of constructing a Sunny with plans to convert it to an Ember later on. A bunch of us are getting Edmunds Optics's Vis 0-coated f/7 acromatic doublets to put in our Embers, but the stock f/4.4 optics should work great too: that's what I'm starting with. Analog Sky runs a great support forum for builders who have bought their instructional video series ($40 for Magic, $50 for Sunny), and it's so easy to build, many members have done it as a project with their young children.

 

One of the other things I really enjoy about the scope is how receptive Analog Sky is to feedback: there have been a couple of revisions of various parts of the scope to make it better. Not only do I get to make my scope better, unlike the take-it-or-leave-it attitude of the large companies, but I can do it myself too. As someone who's been bitten more than once by the dismissive responses from certain large astronomy companies, this is a very refreshing attitude. The Vis 0 hot-rodding mod is an example of this, as well as plans for upgrading the cheap mirrors to Antares mirrors in the future, along with a bunch of quality of life improvements they've introduced.

 

They just posted some info on Sunny in the vendor forum, or you can search for Analog Sky Magic to find the website. I have no affiliation with them other than being a very happy customer!

Edited by A Y, 03 February 2024 - 06:41 PM.

[CrazyPanda]

Total cost of the entire instrument is between $500 and $1k all-in depending on what options you choose

 

That's a lot of money for what amounts to a basic pair of binoculars. You could spend $130x on a 25x70 SkyMaster which is going to be just as good or better optically as those cheap AliExpress objective lenses...

[Ice Cube]

That's a lot of money for what amounts to a basic pair of binoculars. You could spend $130x on a 25x70 SkyMaster which is going to be just as good or better optically as those cheap AliExpress objective lenses...

or you could build the same with the premium antares optics mirrors and viz-0 objectives from a domestic manufacturer like edmunds optics.

 

pick your price point.

[A Y]

That's a lot of money for what amounts to a basic pair of binoculars. You could spend $130x on a 25x70 SkyMaster which is going to be just as good or better optically as those cheap AliExpress objective lenses...

I don't agree. The 225mm lenses are very good, and I say this as someone who also has Canon 10x42L IS binos that I used for astronomy.

 

But putting image quality aside, Magic is far more than "a basic pair of binoculars":

 

1. It can use interchangeable eyepieces with full illumination of 2-inch eyepieces, so you can get a huge FOV, and huge exit pupil with longer focal length eyepieces (great for those big DSOs like the Veil), or you can increase magnification with shorter eyepieces.

 

With my APM 30mm UFF eyepieces, I get 7.5x, 9.3 degrees true FOV, 70 degrees apparent FOV, and a 6.8mm exit pupil. Only a Nikon WX is in the same ballpark, and I don't need to tell you how much those cost! Later on, I can change to some 17.5mm Morpheus and get a really pretty view of the Pleiades, and then with the 4.5mm Delos, I can easily see the bands on Jupiter.

 

With your Starmaster, you're stuck at 25x.

 

2. You don't need to crank your neck to use Magic: it uses 50mm secondary mirrors to reflect light into your eyepieces, so you look into Magic 90 degrees from where it's pointed, and you don't have to hurt your neck or lie down to look at objects overhead. This also lets them be used on tripods, since binos looking up on tripods are even less comfortable than hand holding. So you get both stability and comfort you don't get with regular binos. 

 

Magic is a 6-inch cube that weighs 3 lbs, so lots of affordable tripods can hold it well.

 

3. Magic has magnetic filter cartridges that hold 2-inch filters, and they slip into slots on either side of Magic, so it's easy to do in the dark, unlike trying to thread on filters. The magnets retain the cartridges in the Magic so they don't fall out. Regular binos can't easily take filters, but I use DGM NPB filters in my Magic all the time. With the large exit pupil, views of large objects are still bright with filters.

 

4. Magic has a built-in laser pointer that you can align so finding objects in it is very easy.

 

5. Magic has collimation knobs to align the mirrors with the lenses, and you can change the collimation while observing in the field with no extra tools. Good luck if your regular binos need collimation after you've accidentally dropped them.

 

6. Other than the optics, Magic is 3D printed, so if you need to repair something, modify something, or install a new upgrade (Analog Sky has put out a number of upgrades based on feedback from early users), just print it, and install it. The parts are all available free for download from places like printables.com. 

 

Recently, I downloaded and printed out new focusing tubes when I upgraded my lenses to the 225mm version. I had the V1 focuser, and the V3 that I downloaded had helicoid threads with a more refined cross section so focusing is smoother. 

 

Since it's 3D printed, other than the parts that have to be printed in black, you can make the other parts of the scope any color you want, and there are a lot of filament colors available out there. The Magic group has photos of some really great looking builds in all sorts of colors.

Edited by A Y, 13 February 2024 - 02:27 AM.