Revitalised German Binoviewer..

[F15Rules]

Hi all,

Some of you may have noticed a few months ago, that I bought an old (20 years or more) set of 60 degree angled binoviewers.

These are branded "Celestron by Baader", but were actually built in the then West Germany in Wetzlar by Leitz Optics, a well respected maker of excellent quality optical equipment.

I believe that these sold for between £600 and £700 when new, which was a considerable sum back then. I was intrigued by the fixed 60 degree angled design and the few reports I could find, which were largely positive.

I got the bv's for a reasonable price and on first light could immediately see that they were optically superior to my Baader Maxbrights - which I then sold on.

However, I could also see that the prisms were a bit mucky looking through the scope connection end, so out came the Baader Wonder Fluid. It was then that I realised that the prism at that end of the binoviewer was loose - as I gently cleaned it with the Baader cloth, there was "give" as I did so..the prism moved at one end, rather like pushing on an unlatched bottom opening window.

This was a blow, and beyond my competence to fix. I had previously read on another forum some posts by a guy in Croatia, Denis Levatic, who is a binoviewer expert and is well known for "supercharging"  all kinds of binoviewers.

So I got in touch with Denis by email and asked if he would be willing to look at the binoviewers for me, and did he think these were worth the effort and expenditure. He asked me to outline the problem  and said that these bvs are of superior quality build and optics to the more modern Chinese mass market versions.

So I sent the unit over to Denis in Croatia. He came back to me promptly to advise that the prism were dirty, one was loose (and would need to be cleaned and re-cemented), and there was some evidence of fungus. So he would need to disassemble, clean, and re-collimate - a significant piece of work. Denis said he would also blacken the prism sides and edges to improve (the already good) contrast levels...See photos.

Well, I just got the Bv's back a few days ago and have to say I am delighted. The prisms are now spotless, collimation is perfect and the the views are superb. I've attached a few shots of the bv's on my Zeiss Telementor, loaded with a pair of Fujiyama12.5mm Orthos. Lovely views of M42 and the Trap!

Based on my experience I would happily recommend Denis and his skills?. More notes to follow as I use them more☺.

Thanks for reading.

Dave

 

[Alan White]

A nice end result Dave.
You have very German set up there, equally nice too.

 

[Stu]

Very nice Dave, glad it worked out well.

I have a pair of TS binoviewers which have had the Denis treatment and which are excellent.

[Peter Drew]

I have a couple of this design, one identical to the Celestron and one just badged "Japan". IPD is adjusted by sliding the eyepiece holders sideways, this of course changes the focus which has to be reset. Although good, I nowadays prefer to use my Denkmeiers.      ?

[F15Rules]

5 hours ago, Peter Drew said:

Although good, I nowadays prefer to use my Denkmeiers.      ?

So, Peter, does that mean you don't want to swap me for your Denks?!?

[Telescope40]

Hello Dave. @F15Rules

I trust you are well.  Would you have any updates re the supercharged BV’s. 

Thinking about having my pair worked on by Denis. 

Regards. John 

[F15Rules]

Hi John,

I'm well thanks, hope you are too?

I didn't actually have my binoviewers "supercharged", but I did have them repaired, (one of the prisms had become detached as outlined above), cleaned and serviced by Denis.

I was very pleased with the work that Denis did for me, and the binoviewers work beautifully now, with great collimation. I'm happy to recommend Denis as a binoviewer expert and I have read good things on CN about his actually supercharging service, which I believe includes full set up, collimation etc as part of his service. 

I can forward Denis' email address to you (or anyone else that's interested) and he would I'm sure be happy to quote you for supercharging your own bv's.. I believe that can add several mm to the clear aperture of standard binoviewers, which is about 22mm. My Celestron's clear aperture is only around 17-18mm but as the views are so good, and I haven't noticed any vignetting with eyepiece pairs up to 25mm focal length, I haven't felt the need to ask if they could also be supercharged?

Regarding the performance of my particular Celestron/Baader bv's,  I am very pleased with them indeed. They are angled at 60 degrees which I find very comfortable unless viewing right at the zenith, (which I rarely do anyway), and I do like the smooth adjusting sliding mechanism to get the IPD just right: as Peter says above, you do have to re-adjust focus when you change the slider distance, but it's not a big issue at all for me.

The build of these German made binoviewers is really solid, typical teutonic engineering, and they do seem to consume a good deal less back focus than other bvs such as Maxbrights. According to one review I read, these binoviewers use only around 14% more back focus than a standard 1.25" diagonal and eyepiece: certainly, I am able to use these on my Tak and Vixen refractors with no OCS/Barlow at most focal lengths, as long as I use short length adapters between the bvs and the scope tube (and the Celestrons are T2 compatible which makes them much easier to source suitable adapters for).

Hope that helps, John ?

Dave

[Telescope40]

Ah. Roger dodger. 

Clear skies.  John 

[F15Rules]

Hi John,

I was editing my previous post with more info and during the process moved from my phone to my laptop as it was easier to type in text more quickly! 
Sorry if the first version of my reply seemed to end abruptly, it should read better now I hope!

Cheers

Dave