Baader ClicklockTM 2" Dielectric Mirror Diagonal
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Second only to eyepieces, a new diagonal tends to be high on a new scope
owners list of "must haves". Most new telescopes ship with a sub-par
diagonal, both optically and mechanically. Plastic housings,
low-quality mirrors, a single set screw with no protection from marring the
shiny barrels of your new eyepieces - it is soon obvious that a replacement
is in order. |
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Many popular eyepieces today sport a 2" barrel, so sales of 2" diagonals
outnumber 1.25" diagonals by far. Of course, most 2" eyepieces are
fairly heavy and many are quite expensive so you'll want that new diagonal
to hold your prize oculars firmly without leaving so much as a scratch on
the barrel. The Baader Clicklock diagonal employs a unique twist-lock
eyepiece holder that grasps an eyepiece so firmly you could actually carry
most telescopes by the eyepiece (not that I would recommend it!). A
simple twist and the eyepiece is firmly locked or quickly released. No
more fumbling with thumbscrews. Baader Planetarium has a long history of designing and manufacturing dielectric mirror diagonals. They were the first to bring a dielectric diagonal to market. The Maxbright was introduced to North America when Baader licensed the name to Astro-Physics and starting providing the mirrors for AP's diagonals. Some years later, AP switched manufacturers for their dielectric diagonals; Baader in the meantime developed new coating processes to address a dielectric mirror's primary weakness - the dielectric coating process stresses the mirror substrate leading to optical deformity. The 1/10 wavefront error specification stated in other manufacturer's marketing material is before coating, even for those premium quartz mirrors. After the reflective dielectric coatings are added, only the center of the mirror remains flat - the closer you get to the edge, the worse the optical performance. In fact, one prominent equipment manufacturer recommends you only purchase 2" dielectric diagonals so that the sweet spot covers wider fields of view. For most eyepieces you will never |
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see the difference, but for high quality wide field eyepieces in a short to
medium focal length telescope, the distortion is noticeable. Enter Baader's dielectric diagonals. The Baader Maxbright diagonal (reviewed here) utilizes a dielectric coating process with an equal number of layers on both sides of the mirror substrate. This results in 1/10 wavelength performance after coating. The Clicklock diagonal reviewed in this article uses a new proprietary coating process which Baader is currently keeping secret. The result is on par with the premium Maxbright process, but at a much lower cost. |
Out of the Box
The Clicklock diagonal is a solid piece of gear weighing
in at just over 1 pound. The distinctive machined aluminum
body features a two layer airbrush paint in an off-white color and
accented with a red stripe and the Baader Planetarium logo on both
sides. The barrel and eyepiece clamp are both a semi-gloss
black. The barrel is threaded for 2" filters and includes
baffling groves and evenly applied flat black paint to reduce
internal reflections. The entire assembly is a fine piece of
equipment.
The dielectric mirror is scratchproof and should last a lifetime of cleaning with reasonable care. The mirror is oversized to ensure full illumination of the widest field 2" eyepieces. Further along those lines, the barrel and eyepiece clamp have no restrictions impeding the light path.
The Clicklock diagonal gets its name from the unique eyepiece holder shown in Figure 1. The brass compression ring (no marks on your eyepiece barrels) hides a unique locking system which securely holds any 2" eyepiece with just a simple twist of the barrel with the knurled rubber ring. The finger lever (that is not a thumbscrew) makes this motion yet easier, even with gloved hands. Additionally, you can feel several click stops which get closer together as you turn the clamp into the locked position. This works nicely in the dark providing positive feedback to indentify the clamp is fully engaged.
The two other methods call for removing the thumbscrew entirely. The first of these methods is intended to convert a 1.25" eyepiece to 2" barrel size semi-permanently. In Figure 6, you will see two holes in the front of the barrel. The top opening holds a set screw which tightens against the bronze lock ring using an included hex wrench. In this manner you can attach the Pushfix to a 1.25" eyepiece and use it in a 2" eyepiece holder or diagonal. To complete the eyepiece's transition to this larger format, the Pushfix is threaded for 2" filters.
A second method uses a set of three nylon setscrews which are evenly spaces around the bottom of half of the Pushfix barrel. The lower hole in the front of the barrel in Figure 6 houses one of those nylon setscrews. With a little trial and error you can adjust the three nylon screws to allow an eyepiece to be pushed into the adapter and pulled out with just enough force to keep it in place.
Conclusion
If you felt the Maxbright diagonal was too expensive but you still want a
premium diagonal, the Clicklock is just what you've been waiting for. The
Clicklock is a clear step above the competition in optical performance and
loaded with unique and useful features, yet competitively priced.
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