Are two eyes better than one...

[josefk]

It was a binoviewer dedicated session for me last night. A first for me and so all new experiences and learnings. I bird spot in my day time hobby and massively prefer the comfort of two eyes over one while doing that so my hopes were high for astro. TLDR: it's six of one and half a dozen of the other just like general opinion tends to suggest it is.

The site was Fineshade Woods. A fine clear steady sky (after the late evening cloud had cleared) with approximately 60 degrees by 5 degrees Milky Way visible overhead. Targets may look arbitrary but i was looking for experience in FOV, two eyed comfort for prolonged viewing and magnitude detection. I was at 102x and 38' FOV and 1.8 exit pupil (*calibrated by whatever is lost from sharing the aperture across two eyes) all night. This is the widest FOV i will be able to get in binoviewers with my current scope.

Planets: On the whole nearly totally positive.

I saw surface colour on Saturn that i have never seen before - a faint grey polar region and two faint bands in line with and just above the rings. The Cassini Division blinked periodically. I'm convinced the binoviewers (and particularly the relaxed nature of "wide eyed" viewing through them) bagged me a moon last night i wouldn't otherwise have seen - Enceladus very very faint and tight  in against the western ring edge - it could be seen as well by holding Saturn just outside the FOV. Rhea, Dione, Titan, & Lapetus also seen. I couldn't detect Hyperion, Mimas and Tethys even after checking exactly where to look.

Jupiter - steadier in the BV then mono. i came here early in the night while Jupiter was at ~20 degrees altitude and I could see the GRS fairly clearly and with three moons. Later in the night when Jupiter was at about 40 degrees i came back and there were four moons showing and a slightly darker more obviously ragged NEB/SEB pair. Other bands only as momentary flickers. 

Mars - gross diffraction spikes (:-() even when dropping a 9mm Plössl in one side of the bino and using one eye to try and throw some light away. Still (to my eyes) quite obviously not round. I would describe it as vignetted by something in my scope if i didn't know better. Lots of ADC and quite shimmery. Very orange.

Neptune and Uranus - pale blue and pale grey little dots respectively even at "only" 102x.

Next check were a bunch of ~10...20' open clusters in Cassiopeia. NGC 654, 663, 659, 129, 225, 436 and others. The larger ones definitely present well at 38' in two eyes but some of the lower magnitude groups i'm not sure. Some were seen and "unpacked" but only using averted vision. NGC 457 on the other hand (the Owl Cluster) was superb. Absolutely striking and fantastically aesthetic at 38' using both eyes - better than mono (for me) for sure. NGC 581 was also lovely in this area.

I targeted a few Planetary Nebula next; M57, M76, and NGC 7662. I don't think these objects were flattered by this viewing configuration. M57 i know well and love to look at but i could see much less detail using BV on this night than in previous visits.

I also wanted to try a few faint galaxies. I found NGC 7331 (Caldwell 30) and found it definitively but only because of a nearby striking star pattern holds the eye. I couldn't detect anything else on my list in this area (e.g Stephens Quintet). I think i was running out of detection around +12mag.

Finally I targeted  a few nebula tonight - i wondered if the improved SNR of two eyes would help even while i am not using filters - while it felt quite close at times i can't say i detected any of Gamma Cassiopeia Nebula, Cocoon Nebula, or North America Nebula. Any tips on these gratefully received :-).

So a qualified success but more to learn and tune. This was a long session (~7hrs) but totally comfortable.

Cheers all

Joe

 

 

 

[Paz]

Great report, I think binoviewers are great and good for most targets. These days my default preference is to use binoviewers. I only go cyclops if I want an easier/simpler/lighter set up or if I'm going for really faint or really big targets.

[Peter Drew]

Yes, that's why nature gives us two.      😀

[paulastro]

For years, I've used a binoviewer for the Moon and planets, for me the improvement is significant.  The great thing is you don't need expensive eyepieces.  In side by side comparisons a pair of Orthos in a binoviewer has always given better views than when using single high quality expensive eyepieces, including Monos and Ethos for me - and other experienced observers viewing at the same time.

[josefk]

3 hours ago, paulastro said:

For years, I've used a binoviewer for the Moon and planets, for me the improvement is significant.  The great thing is you don't need expensive eyepieces.  In side by side comparisons a pair of Orthos in a binoviewer has always given better views than when using single high quality expensive eyepieces, including Monos and Ethos for me - and other experienced observers viewing at the same time.

I got a hint of that i think on Friday on Saturn in particular - i only have one EP pair at the mo' but i will hopefully secure a pair of shorter focal length ortho's or Plössls for the autumn period. I'm waiting for a GPC first and that will tell me exactly what focal length to pick - somewhere around 15...18mm i think. 

i think someone else already commented on SGL that the advantages of binocular vision is something you can prove for yourself (or not) trying to read an eye chart (or some small print) with either one eye and then combined two eyes. Works for me. 

[dweller25]

I am a big fan of binoviewers.

[Macavity]

(Randomly) The advantage of using two eyes are anecdotal. I must try! 😎
But I do wonder about the "magnitudes"... due to transmission/reflection.

Edited August 23, 2022 by Macavity

[josefk]

21 hours ago, Macavity said:

(Randomly) The advantage of using two eyes are anecdotal. I must try! 😎
But I do wonder about the "magnitudes"... due to transmission/reflection.

i know what you mean - i was looking to gather experience of that for myself but i didn't set about it in a structured way (i.e i didn't set about working up and down lists of known objects/known magnitudes and comparing bino to mono) so my 'findings' aren't particularly informative even for myself. I was hoping for a dimming effect on Jupiter and Saturn but didn't experience it in a notable way. Big disclaimer - i can't switch between bino/mono quickly (different back focus requirements) so didn't do any kind of AB test.