Are the BBHS coatings easy to clean? Do the coatings have a life comparable to your dielectric coatings? Do the coatings degrade over time and at what rate? Is there a difference in performance between your dielectric diagonal and the BBHS one, what are the differences and are they significant or very slight? I own an early Televue APO 4 inch refractor.
Question by: John on Sep 9, 2016 1:29:00 AM | 1 Answer(s)
BBHS-mirror coatings require the same care during cleaning as you would give to the protected aluminum-coatings of a Newtonian telescope. Only dielectric coatings have the ultimate hardness to withstand any kind of mistreatment during a cleaning procedure - very similar to our Phantom-Group hard antireflection coatings applied onto our lens surfaces.
Any reflecting telescope with classic coatings can attain a lifetime of 20 or 30 years - correct handling provided. The same accounts for our protected silver-coatings, whereas the position of a stardiagonal within the optical train does provide much better protection against environmental influences, compared to the exposed surface of a primary telescope mirror.
We do regard the benefit of the BBHS hardsilver coating to be quite noticeable, compared to the reduced spectral range offered by a dielectric coating. Please check in the Internet for statements that would verify our position. Or look for the very extensive tests on star diagonals, performed by William Paolini (see tab "Downloads".
Please read more on the properties of our star diagonals and our design philosophy here: http://www.baader-planetarium.com/en/blog/baader-bbhs-reflective-properties/
Answer by: Baader Web Team (Admin) on Sep 15, 2016 8:22:00 AM
I have treated myself to this Baader Amici Prism!! However - I am now concerned with reading reports from online astronomy forums regarding this prism sometimes causing a 'roofline diffraction spike' in the eyepiece image. Will this happen to me?? I will only use the prism for visual astronomy, not photography. Focal Ratio of my telescope = F10, focal length = 2800 mm. Celestron CPC1100. Most of my viewing will be in the 100X to 250X magnification range. Thanks for any reassurance you can give me! PS I love your products!!
Question by: Blue Ridge on Aug 15, 2020 9:51:00 PM | 1 Answer(s)
This can happen sometimes - "sometimes" is, when you observe a very bright object and place it directly onto the roof edge. If you move it a little bit of center, it is no problem - please try it out!
This is typical for all Amici (rrof) prisms, similar to the spikes of a Newtonian telescope, but much weaker.
Answer by: Baader Web Team (Admin) on Aug 18, 2020 11:13:00 AM
What advantage does the amici have over the roof prism? Which is better for astronomy? which is better for terrestial?
Question by: Allan Smith on Mar 25, 2017 8:38:00 PM | 1 Answer(s)
In Europe the roof-prism was invented by an Italian calles "Amici" - thats why its called Amici-Prism here. The difference lies in the quality: the extreme accuracy of the roof edge and roof surfaces. Most roof prisms are only made precise enough for low mag terrestrial viewing. Otherwise the production cost would get too high.
The amici/roof prisms that we supply with the BBHS-coating all are made according to the original optical specifications by Carl Zeiss. This is the reason for the high optical quality - good enough for high magnification work ( - and for the price as well).
Answer by: Baader Web Team (Admin) on Mar 27, 2017 9:07:00 AM
What is the weight of this reference # 2456120 please ?
Question by: mathieu on Dec 17, 2021 2:53:00 PM | 1 Answer(s)
Its weight is ca. 660g.
Answer by: Baader Web Team (Admin) on Dec 20, 2021 11:33:00 AM
I own a new Stellarvue SVX 130T f7 refractor. Is this scope too fast to be used in this high end amici prism diagonal? I understand it works well with long f ratios. Is 7 not applicable? Perhaps the non amici version is better suited for f7 refractors? Thanks. Davis.
Question by: Davis on Feb 27, 2022 4:34:00 AM | 1 Answer(s)
The amici prism will work well with your telescope
Answer by: Baader Web Team (Admin) on Feb 28, 2022 9:21:00 AM
Is it possible to have the same quality (suitable for hight magnifications) with an erecting capacity ?
Question by: Jean-Noël FERRIER on Sep 29, 2017 9:28:17 PM | 1 Answer(s)
Keep an eye open. We will soon relese a new batch of 2" Amici Prism with BBHS Coatings.
Answer by: Baader Web Team (Admin) on Oct 4, 2017 8:29:00 AM
I want to be sure that the Baader 2"/90° Astro Amici-Prism with BBHS ® coating is compatible with all the eyepieces : I have a set of televue ethos and I want to check that the ethos will not bottom the prism inside.
Question by: J-François on Aug 19, 2020 12:56:00 PM | 1 Answer(s)
Eyepieces with 2" barrels of up to ca. 45mm length can be used without problems. If an additional 1.25" nosepiece is in front of the 2" nosepiece, you can use any 2"/1.25" reducer to be safe, or use our Pushfix #2408151 to expand the 1.25" barrel permanently to 2".
Answer by: Baader Web Team (Admin) on Aug 19, 2020 1:29:00 PM
Should I unscrew the 2" nosepiece of this eyepiece by hand? If so, it should be clockwise or conter clockwise?
Question by: Rafael Sampaio on Jul 2, 2020 8:05:00 PM | 1 Answer(s)
You can unscrew it by hand, there are no tools necessary. To unscrew it, rotate the nosepiece counterclockwise.
The Clicklockk is held in place with the tiny screws at the side, but the noseiece is only screwed onto the body. It is the part Baader 2" Safety Kerf nosepiece with 2" filter thread # 2408156 with a regular thread (an SC-thread).
Answer by: Baader Web Team (Admin) on Jul 3, 2020 8:09:00 AM
Is a roof line spike visible using the 2" Baader Amici prism in the telescope at low or high power? I plan to use the prism for astrophotography and really need the short back focus that this diagonal provides.
Question by: Joel Cohen on Sep 12, 2019 11:20:00 PM | 1 Answer(s)
We do not recommend Amiciprisms for astrophotography at all. The problem is the colour fringing and contrast loss that happens because of 3x internal reflexion. Even highest quality Amici Prisms do have these effects wich are visually not disturbing and barely visible. But photo quality will decrease significantly. Genereally it is recommened to have a straight beam path for Astrophotography. The less glass is in between the collecting optical element (mirror or lens) and the camera, the better it is.
Answer by: Baader Web Team (Admin) on Sep 16, 2019 9:14:00 AM
Baader 2"/90° Astro Amici-Prism with BBHS ® coating + Baader 2" NexStar locking ring is compatibe with OTA Nextar Evolution 9.25?
Question by: Jordi Puig on Feb 24, 2021 7:01:00 PM | 1 Answer(s)
Yes this will work. Just unscrew the visual-back and turn down fully the locking ring. Then unscrew the 2" nose piece off and turn down the
amici prism fully. Now just turn back to your appropriete position, maybe up-rigt, then turn back the locking ring to fix this position.
Answer by: Baader Web Team (Admin) on Feb 25, 2021 11:48:00 AM
I have the 2456120 diagonal, and it's fine. However the Clicklock-SC clamp I use to fix the diagonal to my C9.25 SCT is too thick. What I really want is something with an SC-thread for the scope and on the other end, something to fit directly into the prism housing. Is there such a thing?
Question by: Bryan Dawson on Jul 15, 2018 10:37:00 PM | 1 Answer(s)
You already have the solution (almost): Like on most of our 2" star diagnals, you can remove the 2" nosepiece and then have a 2" SC thread, so you can screw the prism directly onto the SC-thread of your telescope.
Of course, it will usually end up in an uncomfortable position - but we offer the NexStar Locking Ring 2458270 which works as counter nut.
To attach the prism housing to your telescope, you may have to unscrew the eyepiece clamp, because otherwise it may hit the focus knob when you screw the prism onto the telescope.
Answer by: Baader Web Team (Admin) on Jul 16, 2018 9:22:00 AM