Upgrading: Baader T2 Maxbrite vs BBHS diagonal, recomendations?

[konza]

I'm peicing together a new diagonal for my ES 102 f7 triplet refractor. Usage is visual only. Most used eyepieces are ES 68ᵒ 24mm & 16mm, and rarely 82ᵒ 8.8mm. I tend to seek out star clusters but anything is fair game. I favor the Baader option both on reputation and a dedicated 1.25" eyepiece holder can be fitted without the need for a reducer...all my eyepieces are 1.25". Is one or the other a better match for the above considerations?

[Bigzmey]

Both are good quality products, between the two mirrors I would pick BBHS. However, for your scope I would go with Baader T2 Zeiss Spec Prism.

As you see from my signature I have a few high quality mirror and prism diagonals and after side by side testing I use prisms exclusively in my APO/ED refractors.

Main reason is that prisms produce less light scatter compared to mirrors which results in sharper stars and better planetary details. BBHS mirror comes very close to Zeiss Spec Prism, so if you mind set on mirror go for BBHS.

[Lady Fraktor]

Before buying a prism for a fast refractor you need to determine if it will benefit from using one.
Do a star test and on inside focuser look at the first ring.
If it has a red tinge to it then a prism could be useful.
If the ring is white/ neutral then a mirror will be the better choice.

[Bigzmey]

Before buying a prism for a fast refractor you need to determine if it will benefit from using one.
Do a star test and on inside focuser look at the first ring.
If it has a red tinge to it then a prism could be useful.
If the ring is white/ neutral then a mirror will be the better choice.

I guess "fast" is relative. To me F7 is not fast. Anyway, the mileage will vary but in ES APO scopes I had I did not see any added CA from prism, but noticeable improvement with light scatter compared to dielectric. I even see improvement in Onyx F6.3 80ED

[Lady Fraktor]

You should check anything faster than f/10 according to Baader and TEC.

[konza]

Lady, wonderful tip to star test and check for red tinge. Being on the cusp of things with an f7 scope was giving me fits. Star test at 151x(4.7 eyepiece) showed no red or any color in or out and nice concentric rings. Thanks for sharing your knowledge!

[Jones]

The BBHS mirror enhances red stars, all those red giants in the double cluster are easier to see in small scopes.

The Zeiss t2 Baader prism is the absolute best for planets because of minimal scatter.

[Shorty Barlow]

The BBHS prism is quite compact compared to the standard T2.



I have both sitall mirrors (BBHS & dielectric).



The BBHS is supposedly better at the red end of the spectrum.



The BBHS prism is very good and has transmission very like the Takahashi prism. They all seem the same to me on my f/7 refractor.

[Lady Fraktor]

The BBHS mirror enhances red stars, all those red giants in the double cluster are easier to see in small scopes.

The Zeiss t2 Baader prism is the absolute best for planets because of minimal scatter.

I prefer the 2" amici myself.