Maxbright II in a 12” dobsonian

[bosun21]

I have just ordered a 12” dobsonian but for the life of me I can’t seem to track down the Baader GPC for Newtonians. Does it have to be this specific one or can another one from a different manufacturer work just as well? I’ve been quoted April at the earliest. Thanks 

Edit: I have now been told by Baader that they have discontinued it. I now have an expensive paperweight.

Edited January 11, 2023 by bosun21
Additional details

[Space Hopper]

You want Baader item #2456300/1

As you say, it looks like they are out of stock for the foreseeable.

Maybe worth putting out a wanted ad ?

I've used one myself in the past ; they do work ! I had an OO VX12 Dob with it. It corrects for coma as well.

(When i say they do work, i tried using a 'normal' 1.7x gpc, but it was nowhere near able to focus) Another option is to try a 'Powermate' 2x or...if you've ordered 

something like the SW Flextube, try lowering the poles a bit to throw out the focus a bit. 

 

[bosun21]

26 minutes ago, Space Hopper said:

You want Baader item #2456300/1

As you say, it looks like they are out of stock for the foreseeable.

Maybe worth putting out a wanted ad ?

I've used one myself in the past ; they do work ! I had an OO VX12 Dob with it. It corrects for coma as well.

(When i say they do work, i tried using a 'normal' 1.7x gpc, but it was nowhere near able to focus) Another option is to try a 'Powermate' 2x or...if you've ordered 

something like the SW Flextube, try lowering the poles a bit to throw out the focus a bit. 

 

I’ve actually bought the Stella Lyra 12” dobsonian and a new Maxbright II binoviewer. Baader stated that it’s been discontinued, so not going to be restocked. As I’ve just sold my 102ED Starfield I can’t use them at all. If I knew that a 2.5 power mate would work then I would buy one, but I don’t want to buy on the off chance that it will work. So Baader have left everyone with a Newtonian screwed if they buy their binoviewer. I think I’ll be sending the Maxbright II’s back for a refund. As they are useless to me without the Corrector. 

[JTEC]

I routinely used a 2” Televue Powermate with the Baader MkV binoviewer in my 12” truss-tube Dob.  

[josefk]

I think (and I can make careful checks for you if you like) that the 2" 2x TV powermate moves the focus point out by ~65mm i.e. it is making a circa -65mm contribution to the light path when used before the diagonal. This is "a bad thing" for my usage but maybe useful for you. Cheers

[josefk]

Hi @bosun21 you may want to disregard my message above - you won't be using a diagonal of course so the measurement i get is irrelevant. A powermate after the diagonal and before the eyepiece is more or less parfocal. Means i have no clue what it would do for you in your situation. Sorry.

[bosun21]

21 minutes ago, JTEC said:

I routinely used a 2” Televue Powermate with the Baader MkV binoviewer in my 12” truss-tube Dob.  

Did you have adjust the trusses for this to work? I don’t have that option with mine being a solid tube. Thanks 

[PeterC65]

I use different kit, WO Binoviewer and Explorer 150PDS, but ...

With the Newtonian I can barely achieve focus with the WO x1.6 GPC so I use my Baader Hyperion Zoom Barlow instead (bought with my Baader Zoom) and that does the job nicely. It does give me x4.0 rather than x2.25 with the Binoviewer though.

I'll be very interested to hear how you get on with the 12" Dob. As you may know, my recent EEVA exploits have been an attempt to avoid perusing the more aperture route!

Edited January 11, 2023 by PeterC65

[Guest]

Welcome to the big dob club.  

[bosun21]

1 hour ago, PeterC65 said:

I use different kit, WO Binoviewer and Explorer 150PDS, but ...

With the Newtonian I can barely achieve focus with the WO x1.6 GPC so I use my Baader Hyperion Zoom Barlow instead (bought with my Baader Zoom) and that does the job nicely. It does give me x4.0 rather than x2.25 with the Binoviewer though.

I'll be very interested to hear how you get on with the 12" Dob. As you may know, my recent EEVA exploits have been an attempt to avoid perusing the more aperture route!

Will do Peter, I have been inspired by watching Tiagos YouTube channel Dobsonian Power, where he is achieving fantastic results using both an 8” and 12” dob. He has them on an equatorial platform and simply a camera and laptop using sharpcap I believe. Cheers 🥂 

[JTEC]

1 hour ago, bosun21 said:

Did you have adjust the trusses for this to work? I don’t have that option with mine being a solid tube. Thanks 

Hi, No it wasn’t needed. The scope was a 12” f6 that was made for me by David Lukehurst. (An excellent scope, by the way.) There was no adjustment possible with the truss poles, nor was any required.  You can decloak the optics of the Powermate and attach it directly to the front of the binoviewer; from memory, this required an inexpensive Televue adapter.  It made for a very solid setup.

[bosun21]

1 minute ago, JTEC said:

Hi, No it wasn’t needed. The scope was a 12” f6 that was made for me by David Lukehurst. (An excellent scope, by the way.) There was no adjustment possible with the truss poles, nor was any required.  You can decloak the optics of the Powermate and attach it directly to the front of the binoviewer; from memory, this required an inexpensive Televue adapter.  It made for a very solid setup.

I’ve got David Lukehurst building me an equatorial platform at the moment. Lovely man.

[JTEC]

5 hours ago, bosun21 said:

I’ve got David Lukehurst building me an equatorial platform at the moment. Lovely man.

Agreed 🙂. He made me an equatorial platform for the 12” - again, it was excellent.  I sold it on with the Dobsonian - one of a long list of astronomy assets I subsequently regretted selling! 

Edited January 12, 2023 by JTEC

[bosun21]

12 hours ago, JTEC said:

Agreed 🙂. He made me an equatorial platform for the 12” - again, it was excellent.  I sold it on with the Dobsonian - one of a long list of astronomy assets I subsequently regretted selling! 

We’ve all sold kit that we have instantly regretted doing so. I doubt it will be my last.

[JTEC]

Indeed!  
I found a pic of the binoviewer with the Televue Powermate ahead of it in the Lukehurst Dobsonian.

[Paz]

I use the max Bright 2 with a 14" dobsonian and looking at my notes I can't see that I got anything else to work other than the newtonian 1.7x gpc but I didn't try everything.

I wonder about options like a 2" to t2 converter then a t2 train with a traditional 1.7x or 2.6x gpc or a shortened power mate into the binoviewer but it would be time consuming and expensive to try other permutations of baader gear and none would be optimised like the newtonian gpc. 

It is a shame they are discontinuing the newtoniam  gpc, it is quite specialist but so is the binoviewer and all its other accessories.

One option is if you can move the primary mirror up the tube and have it located so you can focus, but that would be another major undertaking and make focusing without the binoviewer a new challenge, and you would have to look out for the secondary mirror still catching the whole light cone if you raise the mirror.

There are other binoviewers designed to work with newtonians, e.g. the Binotron 27, it is expensive and I think heavier but would do the job very well.

[Space Hopper]

2 hours ago, Paz said:

I use the max Bright 2 with a 14" dobsonian and looking at my notes I can't see that I got anything else to work other than the newtonian 1.7x gpc but I didn't try everything.

I wonder about options like a 2" to t2 converter then a t2 train with a traditional 1.7x or 2.6x gpc or a shortened power mate into the binoviewer but it would be time consuming and expensive to try other permutations of baader gear and none would be optimised like the newtonian gpc. 

It is a shame they are discontinuing the newtoniam  gpc, it is quite specialist but so is the binoviewer and all its other accessories.

One option is if you can move the primary mirror up the tube and have it located so you can focus, but that would be another major undertaking and make focusing without the binoviewer a new challenge, and you would have to look out for the secondary mirror still catching the whole light cone if you raise the mirror.

There are other binoviewers designed to work with newtonians, e.g. the Binotron 27, it is expensive and I think heavier but would do the job very well.

Exactly.

My own experiences were with an OO VX12 F4 Dob. My story :

I was using a Baader Mk5 bino with a refractor at the time but wanted to use it with a Dob.

OO Newts tend to have the focus point 'quite far out', so much so that you often need an extension on eyepieces to enable them to focus.

This was my experience, so at the time I upgraded to a Moonlite focuser (remember those ?) with an extended 60mm drawtube and used the one inch spacer to get my eyepieces, usually a 2" widefield, to focus.

I then decided i wanted to binoview, but realised i would probably need the Newt gpc to do it.

But before i invested in that i thought i'd try my existing 1.7x gpc to see if that would work. I have all 3 of the gpc's - the 1.25x, 1.7x and the 2.6x that i use with my refractors.

In the Mk5 (as well as the Max 2) the 1.25 and 1.7 gpc's screw into the back of the bino. I tried the 1.7x  but it was not even close to focusing, and it should be noted that i removed the spacer from the Moonlite,

and was using the primary mirror on the lower setting (primary mirrors in OO Newts can be raised up a cm or so to a higher setting)

I then brought myself the dedicated Baader 1.7x gpc / coma corrector for Newtonians, (about £180) and this worked fine, but it tied me into a fairly high power and a loss of those rich field, wide angle views i craved for.

 

As a binoviewing enthusiast, i'd wanted to try a 'Powerswitch' system for a while, as it's the best way to get a lower power magnification to use when binoviewing.

The Denkmeier Binotron 27 system referred to above listed a 'low power setting' on the Powerswich of 1.3x.

But there was another option : a sister company (Earthwin binoviewers) that offered a similar product, with a listed 1.2x low power, in their bino, that was quite a bit cheaper, so i opted for that.

Still a fair old whack pricewise, but it worked, and worked well with the 12" F4.

Low power magnification was around 60x which with my 24mm Panoptics, which gave me those rich field views i was craving. The 'Double Cluster', for example was very nicely framed and looked stunning from a dark site.

The downside was the weight hanging out the focuser at 2.5kg. I had major balance problems - OO tubes a pretty lightweight, and i often used to view with my knee supporting the tube at lower altitudes and the OO's friction brake was next to useless with that weight.

But it was a nice scope and a great binoviewing experience. 

Someone made me an offer for the scope a couple of years later, and wanting to downsize and upgrade my refractor, I sold it, and the Earthwin bino soon after.

 

If i was to have my time again ?

The weight of these binoviewing systems necessitates a big primary to mitigate balance issues, so i'd really look at a bigger scope in the first place - something like a 16" mirror in the F4.5 range*

and then go with a Denk Binotron 27 and use their 45mm OCS which is optimally designed. 

* iIt should be noted that these binoviewers will only pass a lightcone in low power setting of around F4.45 or there-abouts. So with my own F4 scope i was probably losing a bit of aperture and illumination, but not too much to spoil the views.

But with big Newtonians and Binoviewing the Denk system is the way to go I think.. And despite the apparent cost, you get 3 different power level options, so potentially, when you take into account the saving you get buying addition eyepieces, it becomes more compelling.

 

 

 

 

[Louis D]

I use the nosepiece of a vintage Meade 140 2x Barlow which operates at 3x in my Arcturus binoviewer to reach focus in all of my scopes.  My Dob is setup with maybe 25mm to 30mm of in-focus from its focus point.  The Meade nosepiece results in very sharp views.