MAXBRIGHT II with SW BD 120ED

[Fedele]

Hi to all. 

I know that the binocular turret can't reach the focus with the SW Black Diamond 120ED.
1) Can you confirm me?
2) how can i solve? I have a 31.8 "diagonal prismatic, a Barlow 2X TV, several Ploss TVs. I would like to avoid adding OCS.
3) do I have to bray the tube? as?
4) could the replacement of the stock focuser with another focuser be enough? what model?

thank you

[Robindonne]

I, as a non-expert, would cut 8-10 cm off of the tube.  Reinstall the focuser and keep a set of extenders around.  😬.  But on the other hand, cutting in a tube....😪

[johninderby]

Cutting a tube takes care and attention and does require some DIY skills but can be done. I’ve done it to a couple of scopes and the trickiest part is making the cut square to the tube. Wrapping a sheet of paper around the tube can help check how square the cut is. 

The scope will also need collimating afterwards of course. I use a laser and print out a bullseye target on thin paper to fit the objective. If the focuser isn’t adjustable there is usually enough wiggle room using the screws where the focuser fastens to the tube.

Edited February 1, 2021 by johninderby

[Star Struck]

You do not need an OCS, but you will need some kind of Barlow.

Easiest option is to screw a t2 1.25 nosepiece into the t2ring on the binoviewer.

 

Then buy a Barlow nosepiece and screw it onto the end of the t2 nosepiece.

 

it worked for me on a similar scope.

[Ricochet]

The higher the focal ratio, the better the binoviewers will perform. You should try to use a low power eyepiece with a barlow or gpc rather than no gpc and a high power eyepiece. The only reason to cut the tube would be if you want to have the option to reach the maximum field of view available from a 1.25" eyepiece with your telescope. 

[Fedele]

You think that a fok like this can work?

https://www.teleskop-express.it/focheggiatori-/3521-focheggiatore-tecnosky-v-power-per-rifrattori-tecnosky.html

 

[Star Struck]

The problem you have is lack of infocus. Changing the focuser will not help.

[F15Rules]

If your focuser is standard Skywatcher I think it has an M57 male thread? If so, this adapter might give you more inward focus capacity if your prism diagonal has a T2 female connection, ie. if it's a Baader T2 prism?

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p1431_TS-Optics-Adaptor-from-M57-to-T2-Filter-Thread.html

Hope that helps..

Dave

 

Edited February 3, 2021 by F15Rules