Quick review/experience with the Baader Short Clamp, M72/M68 to Takahashi adapter & Maxbright binoviewer.

[mikeDnight]

 Since 2008 I've been an avid binoviewer user. The binoviewer I bought back then was a Revelation generic model found under various brand names. Mine cost only £99 and so has proved to be my most used, single biggest game changer accessory in my 43 years as a visual observer. I couldn't imagine a better view of the Moon and planets, but Stu planted the seed for a Maxbright ll binoviewer, and the motley crew in the pic below watered that seed while I was at the Practical Astronomy Show in March. 

Dave (F15Rules), Me , Keith, Alan (Alan White), John (Telescope40) & Steve (Saganite).                                                       [The Old Astigmatic Society]

 

Overpowered, I succumbed to their influence and bought a Maxbright.  The very first view through the viewer settled my mind as to its value and quality. Bright, clean, pure, sharp, are just some descriptive terms but I'm sure I can think of more, with the Revelation appearing dim by comparison and with a noticeably dimmer view in the right side of the viewer. The Maxbright displayed even brightness! Mechanically too the Maxbright is obviously superior to the generic revelation model, with excellent click-lock's on both eyepiece holders, and lovely sliding focus switches allowing precise focus for each eye. It wasn't cheap, but it is worth every penny. Using my 25mm pseudo Masuyama's, the brighter deep sky was very impressive, and that made me want to use the 35mm pair I have which are wonderful eyepieces. The Revelation has now been donated to Kieth!

 Focus issues!  This isn't a problem with the Maxbright, but rather with my refractor, or more accurately, with Takahashi. Tak are notorious for having limited inward focus. I think they make their scopes this way so you've got to buy their eyepieces?  Anyhow, I have a beautiful pair of 35mm 5 element pseudo Masuyama's, but they require more inward focus than most other eyepieces of their focal length, and they wouldn't reach focus with the standard Tak 2" back. What to do???

 Auntie FLO came to my rescue.  It was suggested I try the Baader adapters in the images below, as they connect directly to my FC100DZ focuser. 

The advantage over the stock Takahashi visual back is an extra 16mm of inward focus. Though you'll still need to use the Tak drawtube adapter which is a shame.

In this configuration the extra 16mm of inward focus was enough for me to achieve native focus with my 35mm eyepieces, but there were obstacles to overcome!

Using my Baader Zeiss BBHS prism diagonal with the 2" Baader Clock-lock interfered with the new adapter and full insertion wasn't possible as the bulky click lock hit the adapter and locking screws leaving two or three millimetres of the 2" barrel protruding.

I changed the 2" click-lock for the Baader helical focuser, which allowed for full insertion but the light path was still too long. My only other option was to remove the helical microfocuser and attaching the Maxbright directly to the diagonal prism. Bingo! The 35mm's snapped into focus with oodles of room to spare.  What a relief! 

 This of course means that whenever I want to use my 35mm eyepieces I must connect the Maxbright directly to the prism, but honestly it's a small inconvenience compared to the views this scope, binoviewer, BBHS prism and eyepiece combination offer. It may mean however, that the 2" click-lock that is essentially brand new, being only a couple of weeks old, will need a new home. I only have one 2" eyepiece and can use my 2" diagonal for that! 

 

 

Edited April 11, 2023 by mikeDnight

[Franklin]

8 minutes ago, mikeDnight said:

 This of course means that whenever I want to use my 35mm eyepieces I must connect the Maxbright directly to the prism,

You'll have to get a second Zeiss BBHS prism Mike and leave it permanently on the bino's, saving the Clicklock one for cyclops😁.

Lovely set up!

[mikeDnight]

10 minutes ago, Franklin said:

You'll have to get a second Zeiss BBHS prism Mike and leave it permanently on the bino's, saving the Clicklock one for cyclops😁.

Lovely set up!

Another helpful seed planted! 

[Space Hopper]

One small issue i see here, is if you want to add / change a GPC.

The supplied quickchanger coupler makes this much easier.

But pleased to hear you are enjoying the Max 2. The eyepiece holders and diopter adjusters are are treat to use aren't they ?

[Telescope40]

Hi Mike. I use the exact same adapters on my FS128. Works nicely just as you explain. 
I have 2 Baader diagonals - not the BBHS - as  suggested. 
I’ve not tried to work out the magnifications I get to use now.  I just enjoy the views and options I now have by also using a Barlow/GPC. 
 

John 

[John]

Getting those 35mm eyepieces to reach focus can be a challenge even without a binoviewer - I used to have the Celestron Ultima version but could not get it to reach focus even without a BV in place when used with the TAL 100 RT that I had back then. 

The 35mm's of that design need more inwards focuser movement than any other eyepiece that I've used. This is because the field stop of the eyepiece is positioned well above the shoulder of the eyepiece (which is where the chrome barrel meets the black eyepiece body). Most eyepieces have their field stop more or less at the shoulder or a little below it. With these 35mm's the field stop is so wide that it cannot be accommodated within the constraints of the 1.25 inch barrel so they moved it upwards and consequently they need that much more inwards focuser movement.

They are lovely eyepieces when you do get them to reach focus and I'm pleased that you have found a way to use them with your new BV's 🙂

[MalcolmM]

It's reassuring to me that someone as experienced as yourself @mikeDnight needs a little trial and error to get Binoviewers to focus with a Tak! I must have gone through half the Baader accessories to get my WO Binoviewers to come to focus! Then I went through the other half when I got the Maxbrights!

Some people only seem to use them for lunar and planetary but with 28mm Erfles and no GPC (yet more playing around to reduce the light path), I find them very relaxing and immersive for low power wide(ish) field viewing.

Malcolm 

[Stu]

Great review Mike, worth persevering to get the setup just as you want it.

FLO just got some stock in so rather crazily I’ve ordered a second pair so I can do side by side White Light and Ha solar observing with matched binoviewers. Looks like they still have five sets available if anyone is looking for them.

[Paz]

Nice review, you have passed the initiation process of having to try out various contraptions and permutations to get it working but once it's working its great!