Knighty2112

25 minutes ago, Louis D said:

Oh, they'll vignette more than a little.  The outer 25% drops off to blackness before the fieldstop in my Arcturus binos.  I still like the views of nebulae in them because it really brightens them up by compressing all the light into a smaller image than with higher powered eyepieces.  That, and the eye relief with glasses is super comfortable.  Enjoy using them.  They're a lot of fun once you get a good setup.

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

30 minutes ago, F15Rules said:

Your 32mm plossls will likely vignette a little (show a darker edge to the field of view) but should still give a nice view..(the longest focal length EP you can use in a 1.25" barrel with the widest true field of view is around c25mm.

As your binoviewers have a maximum clear aperture (diameter of barrel on the binoviewer eyepiece side) , any eyepiece with a wider than 20mm field stop will vignette ( ie you lose some of the light). I think that's right:-)

Dave

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.  

35 minutes ago, F15Rules said:

Tony is right, this is cheapest way to buy the Baader set. Its a superb setup and because it uses a prism, not a mirror, it has a significantly shorter light path and so takes up less of your precious in-focus:-)

Dave

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. 

1 hour ago, Stu said:

Yong, I'm far from an expert on these things, but I thought the light path through the prism still reflected off the back internal surface by total internal reflection?

As I understood it from EdZ's post, it's the refraction of the converging light beam that actually shortens the light path.

As said, and this emphasises the beauty of SGL, I'm learning again today as I've never considered this stuff before, all very interesting.

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

1 hour ago, YKSE said:

I think a shemetic drawing of light path through these diagonals might partly explain the differences:

Mirror diagonal:                                                                                                                        Prism diagonal:

                                                          

For mirror diagonal, light path should be roughly diagonal size (2" or 1.25") plus the thickness of diagonal walls, while it's about 0,71x diagonal size for prism diagonal.

As an example, Baader's T2 mirror (2456100) has light path 53mm, while T2 mirror (2456095) has 41mm, that's about 0,77x, roughly right.

 

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

3 hours ago, Star Struck said:

A lot of getting Binoviewers to work is suck it and see as you will discover.

One thing not mentioned so far is Inter Pupillary Distance i.e. the distance between the centre of your eyepupils. I have found this to be critical for Binoviewers, a lot more so than for normal binoculars. I could not get the images to merge unless I got this spot on. It is easy to measure yourself, but if you wear glasses then your optician should know what it is exactly as they use it when making sure your glasses fit correctly.

This is the prism I use, it represents very good value for money if you cannot get your existing mirror diagonal to come to focus: http://www.365astronomy.com/Baader-Prism-Diagonal-T-2-90-degree-32mm-Set.html?gclid=COzow5qJqs4CFXYW0wodF4gKqg

Tony

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!  

2 hours ago, Star Struck said:

A lot of getting Binoviewers to work is suck it and see as you will discover.

One thing not mentioned so far is Inter Pupillary Distance i.e. the distance between the centre of your eyepupils. I have found this to be critical for Binoviewers, a lot more so than for normal binoculars. I could not get the images to merge unless I got this spot on. It is easy to measure yourself, but if you wear glasses then your optician should know what it is exactly as they use it when making sure your glasses fit correctly.

This is the prism I use, it represents very good value for money if you cannot get your existing mirror diagonal to come to focus: http://www.365astronomy.com/Baader-Prism-Diagonal-T-2-90-degree-32mm-Set.html?gclid=COzow5qJqs4CFXYW0wodF4gKqg

Tony

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.  

15 minutes ago, Stu said:

It is worth considering the Baader T2 diagonals or prisms as they give a larger clear aperture but still have a short light path helping you to reach focus.

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? 

3 hours ago, Louis D said:

I couldn't reach focus with my OPT 2" dielectric diagonal my AT-72ED, so I ended up getting a 1.25" WO CF dielectric.  It works great, no flexing, no induced aberrations, and it weighs less.

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

32 minutes ago, Charic said:

The 6mm SPL is a  fine eyepiece indeed.  I tried purchasing their 3mm to complete my set, but the seller  refused to budge from their price which was almost retail, telling me its still  brand new in a box , I'm sure that EP  was auctioned three times to the best of my knowledge,  because the price was too high (I assume)  yet he  second hand ones I've purchased were mint, and nowhere near the price he was asking, so still waiting, to complete that set. 
Again, as for the rest of my EP collection, my 6mm SPL was bought on recommendations from other users here at SGL, and I have no issues with it.  I could not buy  a 6mm Starguider, and I really wanted/needed one, so the 6mm SPL was it's replacement. I have other 6mm eyepieces in my collection, and reading a  few lines today from  a document on the web, it said  something like,  some EP's cost more, some work better, but the ones that cost more are not always better? On paper they may be, but your eye, telescope and conditions will dictate whether an eyepiece is good or not. Hands down, I still prefer my BST's, and sorry,  but my 6mm SPL is not yet available to complete your 6mm WO  Bino experience, if that's an option for you.
They say looking at the Moon through binoviewers is awesome, virtually  3D, so how will they compare to standard binoculars, I'll be interested to hear your review.

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!  

26 minutes ago, Star Struck said:

I bought the dedicated WO 2.0 barlow from Agena Astro in the States, didn't cost much.

 

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

3 minutes ago, Star Struck said:

Which type diagonal do you intend to use with it?

I had to buy a Baader prism (non-Zeiss) to get the required back focus.

I bought the dedicated WO 2.0 barlow from Agena Astro in the States, didn't cost much.

 

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.

6 minutes ago, Mak the Night said:

I have some WO bino's. I don't use the 20mm SWAN's that came with them anymore though.

I also have the 2x Barlow element, FLO can order it if you want it.

The WO bino has compression rings in its dioptres so I tend to use eyepieces without safety undercuts for ease of extraction.

The two TeleVue 15mm Plossls are fine as they have lower lip flared undercuts. Oddly the WO SWAN's have tapered draw tubes which can mangle compression rings.

I swapped the draw tubes on these Celestron (GSO) Plossls for chromed brass smooth types.

I don't tend to put the bino into a diagonal with a compression ring as a rule as it also has a flared nose, as a consequence the nosepiece can get marked by the set screw.

They are great bino's though.

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

Just now, xtreemchaos said:

well done Knighty, wouldnt mind some of them myself, dont forget to write a review when you have had a bit of skytime with them, hope you get clear skys .charl.

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.  

6 minutes ago, Dave Lloyd said:

Looks good mate. Skyatnight mag gives it a good write up on FLO's website.

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? 

According to Celestron's own web page the scope comes with a 25mm & 9mm EP's, with stated magnifications of 26x & 72x respectively. The 25mm EP will give good wide field views for DSO's, the 9mm would give small but descents views of Jupiter, Saturn & Mars. Did you buy the scope new, or did you get it second hand at all? Either way for more detailed views of the planets you have to get some good Planetary Ep's. A 3mm EP in your scope will give a 216x view of any planet. Given that the atmosphere normally limits magnification to less than 200x this may only give good results when the seeing is very stable. A 3.5mm or 4mm EP will give magnification under 200x, so for most nights these would work better.

Just found this video on YouTube. Sadly in Russian, but you do get to see the kind of payload it can hold. Looks very good to me. Now, just get it over to the UK so I can buy one!  

Be very interested in this when it is finally released. Much prefer alt Alt Az mounts to Equatorial. 

Yes, I ordered a couple of things from  FLO the other week, and arrived the very next day via Postie. Weren't large items, but still quick service.