William Optics binoviewers collimation or issue

[Elp]

I've been wanting to pass on my William Optics binoviewers to someone who can utilise them because on initial tests I couldn't get them to work and they seemed like more hassle (setup, something more to store and carry, needing two EPs etc). So I thought I'd actually try them during the day to test them again and there is something going on with them and am wondering if someone with more experience can help.

I tried this test with my WOZ61 360mm focal length. I couldn't get any discernable detail with the included 1.6x barlow lens so took that off the binos.

This was the view via a standard 20mm eyepiece directly into the diagonal (images arent brilliant due to eyepiece projection):

 

With the EP removed I then put the binos without eyepieces into the diagonal:

 

Then I put the included WO 20mm eyepieces into the bino:

 

I hadn't moved the scope, initially with the two EPs in it was a blur so I refocussed to resolve some sort of image but my concern is why has the view shifted horizontally? I try to move the EPs and there is no lateral play, the binos haven't moved, when I take the two EPs out I can see the trees and roof again. This is why I haven't been able to use them and am wondering what is going on and can it be fixed?

When I look through the binos only in reverse I can see two images so the prism is working but there's an alignment issue somewhere.

[M40]

Could the weight of the eyepieces be causing the binoviewer to shift in the diagonal?

[Elp]

Could be a possibility. Another thing I didn't add to the post, no matter the dioptre adjustment I also couldn't get a 1 image resolution, it was always double vision. I can use normal binoculars fine.

 

Edited January 25, 2022 by Elp

[Louis D]

Does the image alignment vary as the diopter adjustment is spun on either eyepiece holder relative to the other?  My Arcturus BV is only usable with both adjusters screwed all the way down.

I'm not the familiar with the WO 20mm eyepieces, but if they have undercuts, there's a strong possibility that they will tilt during tightening of the holder collet.

Upon looking at the WO BV, it appears to have a single thumbscrew that pushes against a compression ring rather than using a proper collet to maintain centering.  This could be pushing the eyepiece to the side, and if the thumbscrews on both holders are not in the same radial position, they could be pushing the eyepieces off center in different directions.

[Cosmic Geoff]

I have a Starguider budget binoviewer, and found it can be tricky to use.  It adds about 100 mm to the optical path, requiring a major re-focusing.  The distance between eyepieces has to be adjusted to suit your eye spacing. Mine came with a pair of short-barrel 30mm Plossl eyepieces (no undercuts) and it worked much better with these than with my alternative - a pair of 20 plossls, one with undercut. With the latter it was very difficult to merge the images, With the two included Barlows, sharpness was poor except in the middle of the POV.

When everything works right, e.g. on the Moon, the views are amazing.

[PeterC65]

I think I have a similar problem with a brand new WO Binoviewer. I see two images, very close together but still distinct. I can get them to merge only by pushing upwards on the right hand eyepiece, but when I let go the two images return. No amount of eyepiece / dioptre / IPD adjustment will make the problem go away.

The two close images I see are different from the two images (much further apart) that I saw before my brain had worked out how to merge the images. To merge these images I had to defocus my eyes from the two images I was seeing and slowly they came together, but not quite.

The binoviewer is now back with the supplier for them to confirm that there is a misalignment problem and sort it out.

My own experience, and comments I’ve read on SGL, are making me wonder whether eyepiece misalignment is a common problem with binoviewers? Some people love them and others can’t get on with them and I wonder whether this is down to the alignment of the binoviewer they happen to have used?

When I did manage to see a single image with mine the view was VERY impressive, particularly with M42 which jumped out at me like never before. So I’m looking forward to getting back my working binoviewer.

[Elp]

Just an update on this. After much faffing around I did finally manage to get focus through the binos and the 20mm plossls with a 2x telenegative barlow, the included 1.6x I couldn't get focus with two different telescopes, the image is aligned as per with a single eyepiece so there's no alignment issue. My brain however cannot resolve 1 image so I'm at a loss with these.

[MalcolmM]

I also have the WO Binoviewers. 

Sometimes I can merge the 2 images without trying and sometimes I just can't seem to no matter what I do!

I found the more I used them the easier it was to merge the images however, I have not been able to figure out why!

When I was having trouble I played with the IPD, rotated the eyepieces and tried to relax into it all and often this worked.

When it all comes together the views are fantastic in my experience so if I were you, having achieved focus, I would try persevering with a little more faffing around before writing them off.

Good Luck!

Malcolm

[Neil_104]

I see this is somewhat of an old thread but just wanted to share my experience of the WO binoviewers. I find the only way I can get a single image is to screw both diopers all the way down and focus each eyepiece by moving it up and down and tightening the thumbscrew when in focus. I then micro-adjust focus using the telescope focuser as usual. It's a complete faff but it's the only way I can get them to work for me. If the diopters are not screwed all the way down then the eyepiece is kind of "floating" in position and can easily be moved from side to side by pushing/pulling on it slightly - there's no way a single image will ever form while this is the case.

However, once I have adjusted everything correctly they do perform well. I'm not sure I can see *more* detail per se, but the extra comfort is definitely nice. On the negative side, I can also see the negative effects of the atmosphere (e.g. shimmery, wavy image) more also.

Does it make me want to go out and buy a 2nd eyepiece for my entire collection? Far from it. I will probably just stick to a few select ones, such as a good planetary and good deep sky example. HTH

Edited December 22, 2022 by Neil_104

[MalcolmM]

Just goes to show! The trick for me very often was to completely loosen the right eyepiece and let it 'float'.

Despite really liking the WO Binoviewers, I recently bought some Maxbrights. They 'fix' all the foibles of the WO and I have never had any issues merging with them. I think they are brilliant. 

As for eyepieces; I already had a number of pairs but I love binoviewing so much I've doubled up on my Tak Abbes. I'm looking for some light wider FOV ones now too. My partner groans every time the door bell goes and another package appears  At least it's only eyepieces now and not telescopes 

Malcolm 

[Neil_104]

Thanks for the tip on the Maxbrights - I may have to look into them also then 🙂 At first glance the actual body looks suspiciously like the WOs, though I can see from the write up that they have a larger clear aperture so likely aren't just a rebranding with a different eyepiece holders on them. I've heard nothing but good reports about the Click Lock system as well so it's a bonus that they incorporate this.

Was that the doorbell? 😁

[bosun21]

Another massive thumbs up for the Baader Maxbright II binoviewer. I bought a set having never used a binoviewer previously. I had no trouble merging images and could change eyepieces mid session also. I started EEVA and AP and sold them. I think I’ll be buying myself another pair when they are available again.