Binoviewer advice

[mauriciofleming]

Hello!

Do you guys recommend the use of binoviewers?

I've checked older threads, and I understand the down sides are doubling the eyepieces and losing some light, right?

About the light lost, I could later get an enhanced diagonal to minimize the problem.

Plus, looking with both eyes would help me greatly. I wonder if the help of an extra eye isn't greater than the problem of a small percent of light lost.

The binowiewers I found are all made with BaK-4 prisms, so the light lost should be minimal.

Or should I spend this money in better eyepieces? All my eypieces are SkyWatcher Plöss EPs. I heard the large focal length of my telescope doesn't require "super-duper' eyepieces for fine views.

There are so many nice accessories I don't know what to get first!

Cheers

[PaulG]

Hello Mauricio

I have thought of buying some binoviewers myself.

I would think the views of the Moon would be really nice with binoviewers and a couple of 10mm Plossl eyepieces.

I have a Baader Hyperion eyepiece but it is now for sale as I don't think it performs well enough compared to a cheaper alternative eyepiece.

One eyed viewing can be tiring after a while so it must be refreshing to view with both eyes.

I quite like the William Optics binoviewer, I might just treat myself one day.

Paul

[proflight2000]

I have owned a set of binoviewers, found them to be very good, watching in stereo is much nicer on the eyes. Only shortfall is that you need to double your eyepieces.

[philsail1]

Hello Mauricio (and Paul G!),

I use a pair of cheap "Astro Engineering" Binoviewers with both my Celestron C8 f10 SCT scope, and an Orion Optics 8" f4.5 Newtonian Reflector. (I have to remove the extender on the focuser of the Orion to achieve focus with the binoviewers. The SCT is fine.

I was hesitant about buying a pair of binoviewers - mainly due to worries about whether they would reach focus or not. However, I've used them successfully on a TAL100RS 4" refractor, a 90mm Skywatcher Maksutov, and the two scopes I have at present. I find viewing the Moon and planets quite an awe inspiring experience with binoviewers! So much so, that I rarely use a single eyepiece - except when wanting to take photographs, or view deep sky objects.

You don't have to have powerful eyepieces either. I have two 26mm GSO Plossls in mine. These give wonderful stereoscopic views. If I really want to study detail, I put my Celestron Ultima 2x Barlow in front of the binoviewers. Wow! what a view I get of the Moon, Saturn, Jupiter and Venus (I haven't seen Mars through them as yet).

I just sit mesmerised with the close up stereo views. I don't know why, but the views of the Moon through a binoviewer is much more than twice as good as a single eyepiece. It must be something to do with the way our brains interpret a stereo as opposed to a mono view. Saturn really looks like a solid ball through binoviewers - it truly is in "3D".

With regard to light loss. Using 26mm eyepieces I can view some deep sky objects such as the Andromeda Galaxy, and some of the brighter open clusters. Stars present no problems. The Orion Nebula looks OK through Binoviewrs.

If you use say a 32mm set of eyepieces, (without a Barlow) I would think you'd get acceptable views of some deep sky objects.

You have to be careful not to go beyond about 32mm (and then make sure the eyepiece "barrels" are slim (as you need to get your eyes between them to view!). I tried two 40mm Meade Plossls, but they were nowhere near as good as the 26mm eyepieces I use virtually all the time. I tried two cheap 10mm Skywatcher eyepieces in the binoviewers, but found they were too powerfull and didn't provide very comfortable viewing - and they were a bit hard to achieve a sharp focus.

I have noticed with my particular binoviewers, that the views are a tiny bit on the "soft" side of sharp. But again, this is hardly noticeable when viewing, as the super views just take my breath away!

Another thing with binoviewers is that you do need to "collimate" the eyepieces if you change from one set to another. Collimation is very, very easy. You simply focus the binoviewers, and turn one eyepiece (doesn't matter if it's the left or right one) until the view merges into one. Your eyes are so marvellously constructed that you can immediately tell when perfect collimation is reached.

Binoviewers do add a bit of weight to the eyepiece end of a telescope. I find they are more comfortable and easier to use on my SCT, due to the eyepiece always being at the back of the scope. With the Newtonian, you are side on to the scope, and when it swivells to look at another object, the binoviewers can end up in some awkward positions. (You have to ensure they are securely fastened to the focuser).

I am very, very pleased with my "Astro Engineering" binoviewers, and consider them one of my "better" purchases. I would say that as long as binoviewers are suited to your particular scope, you will not regret buying a pair.

Hope my witterings are of some help to you!

Best wishes,

philsail1

[PaulG]

Hello Mauricio (and Paul G!),

If I really want to study detail, I put my Celestron Ultima 2x Barlow in front of the binoviewers.

Hope my witterings are of some help to you!

Best wishes,

philsail1

Hi Phil

Thanks for the detailed report Phil.

Good point, I completely over looked the fact you can use a barlow with binoviewers.

With that in mind I would probably choose a pair of 20mm Plossl as 150x seems to me to be the sweet spot of my 127Mak for high power viewing.

Paul

[mauriciofleming]

Thanks a lot, Phil!

Very detailed review indeed.

I think I made up my mind, as soon as I can save some money I'll buy a binoviewer! There are some cheap options, it's just a question of choosing a good one.

Regarding the barlow lens (plus binoviewer), have you tried it with your maksutov too? Or is it useless?

Thanks!

Cheers

[philsail1]

Hello Paul,

Yes, I would agree that 20mm plossls will work well with your 127mm Mak. (and with 2x Barlow!).

On the C8 I get 57.6x using a pair of 26mm eyepieces (and 115x with the Barlow). This gives me fantastic views of Moon and good views of Saturn (and Jupiter when visible!).

Oh! one other thing. I found that when using binoviewers, I can gently rest my eyes on the actual rubber eyecups without causing vibrations. This makes using binoviewers (over single eyepieces) that much more comfortable.

Regards,

philsail1

P.S. If anyone lives close enough to me in Connah's Quay, North Wales I would gladly loan them my pair of binoviewers to try out. (Sadly they are too bulky - and too much of risk of damage to post).