Knighty2112

Yeah, need to use the WO 2x nosepiece ordered separately to achieve focus, so in reality my 32mm EPs become 16mm. Would be nice to get a wider view though, so may still consider perhaps lopping some off the tube of the ST120 perhaps to do that. I'll wait and see how the new Altair 102mm f11 frac coming next week works with them first before I make any firm commitment one way or the other.

When I put the binoviewer in to my diagonal, which has a compression ring, in only insert it up to the shoulder of where it slopes inwards, that way it is always on a a straight part of the neck of the binoviewers.

Good to know. Do you need to use the 2x Barlow nosepiece to achieve focus to in your scope?

Couldn't see an issue using them in the daytime, but like I said I need to check them on nighttime targets.

Tested the, out in the daytime so far. Couldn't see any vignetting, at least not in the daytime. I'll check them out obviously better when the clouds roll away to view some nighttime targets.

Yeah, that's the one I got too.

Received the WO 2x binoviewer nosepiece from Agena Astro from the US earlier than expected. Screwing in the 2x nosepiece I can achieve focus OK with my new Baader prism diagonal. Still awaiting a good clear night to test them further, but also got another 32mm Celestron Omni EP to make a pair with one I have already, so can use these too in the binoviewers, so hoping to get some nice wide'ish views with them.

Managed to do a quick session earlier on to observe the moon, Saturn & Mars, and all I can say is Wow! After earlier testing during the day I though there may be a problem with the binoviewers, but observing the crescent Moon first off was just brilliant. Had to use my 2x Barlow still to achieve focus, but the view with the 20mm EPs that came with the binoviewer were just wonderful. Then looked at Mars, which although no major detail could be seen, I could just make out the polar cap glinting away, and the gibbous shape very well. Saturn itself was just stupendous, even with all the LP from nearby houses and street lamps too as the grainy picture below shows. Mars is on the right next to the lamppost, and Saturn is to the top left. I also was able to use the 1.6 x nosepiece that came with the binoviewer too, so that I guess gave me 3.6x views, along with 2x views without the nosepiece fitted. Hoping that it is clear for about 11pm when I hope to view M57 & M32. If they look half as good as the Moon, Saturn & Mars earlier then I that will be great.

Got the binoviewers this morning, and testing them out now. Have to use my Omni 2x Barlow with the binoviewers to get focus with my 2" diagonal. Get a good view with the 20mm EP's supplied with them (which with using the 2x Barlow give me 10mm EPs obviously). Tried them also with some stock plossl SW 25mm EPs OK, but when I use stock 10mm plossl EPs I get I weird thing in the right hand view on the binoviewers. I though at first it was just stray light getting in somehow as I was testing during the day, but now realise it its likely due to the prisms themselves in the bonoviewers themselves, however I did put my 10mm ES Maxvision 68 EP in the righ hand side and it went away. What I get with the plossl 10mm EPs is a bright flare at about the 4 o'clock position in the SE part of the EP view. Not sure how much this might be noticible when I use it at night, but wonder if anyone else has noticed this if you use 10mm plossl EP? As these 2 10mm EPs are been Barlow to 5mm EPs is this too much for the binoviewers to cope with?

So if the light has to hit the 45 degree slope of the back of the prism to get deflected up 90 degrees then this is the same surely as the light been deflected up 90 degrees off the 45 degree surface of a dielectric mirror diagonal. So in reality the light path is the same, just that the focus point of the optics are shifted because the prism design is smaller than the design of mirror diagonals, hence the difference is in focul points and not light paths. That seems to make more sense to me.

Uh oh! now I'm getting confused again! Someone pass the ibuprofen please, I feel a headache coming on! Hehe!

Thanks YKSE. That makes sense to me now, thanks!

Went ahead and ordered up one anyway, as like I said I want a replacement one for my smaller scope so I thought what the hell! Kill two birds with one stone like they say! Hehe!

Thanks. I saw that one whilst looking too. Going to see how I got with what I've got first off, and then if I do need one I may get this one. I do want a new diagonal to replace the stock one on my smaller 70mm frac that I use occasionally over my ST120, so at some point I will get a new diagonal regardless anyway.

Thanks Stu. I am confused by these diagonals, as the don't come with either an eyepiece barrel, or a barrel to fit into your telescope focuser as such, so would have to these buy items them as seperate items to allow the diagonal to fit and work in a scope, so wouldn't this just make them like any other diagonal? Don't quite get how the light path would be shorter than less expensive options here?

Hoping I won't have to, but if I do I would get a WO digonal to go with it too.

I actually dropped my 6mm WO EP about a week ago after finishing off a session and was putting my scope away, and my heart just sank! Expecting major damage to the optics, I was lucky that in reality all that happened was I got a slight scuff mark on the end of the black 1.25" tube that goes into the diagonal. Thankful the optics were still fine!

Thanks. Just ordered from there. Cheers! Not too much either!

Got a Altair 2" dielectric mirror diagonal. Got 80mm focus on my dual sped focuser, so hoping that should be enough also to bring the binoviewer into focus OK.

Thanks. I have a few other pairs of stock EPs that I can use in them too (10mm & 25mm I believe). Can't see the WO 2x Barlow for the binoviewer on FLO. Only place I can see it is on here; http://www.astroshop.eu/william-optics-2x-barlow-lense-for-1-25-binoviewers/p,4717

Thanks Charl. After the obvious cloudy penalty I'll receive for getting them I'll do a first light review when I get a chance to use them.

Yep. I own a WO EP already and it is great quality, so after seeing that Sky at Night gave it the thumbs up too then that clinched it too.

After a little good news (not often that happens right) I have managed to just order a William Optics binoviewer from FLO. Wanted one of these for a while, but was originally planning to get one next year, but managed to bring that forward now, so looking forward to some good views through them in my scopes. https://www.firstlightoptics.com/misc/william-optics-binoviewer.html

Just ordered one, so will get it in a day or two. When viewing through the finder what distance apart are the circles? Are theyroughly half a degree apart, one degree or what?