Question about C-Star Optics TT-150 Telescope

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I am inexperienced at this, attempting to enjoy this with my grandsons...When using the diagonal mirror, what is the difference in using the H20 eyepiece and the SR6 eyepiece? When using the 1.5x Erecting Lens or the 2x Barlow Lens, which eyepieces should I use, the H20, the SR6, or the H1.25? Thank you.

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The numbers on the eyepieces are the focal length in millimetres. You can calculate the magnification of the telescope by dividing the focal length of the main objective by the focal length of the eyepiece in use, so if the main focal length is 700mmm and you use the H20 (Huygens 20mm) eyepiece, you will get a magnification of 35. The SR6 ( Symmetric Ramsden 6mm) would give about 117 magnification. You will find that the LOWEST magnification is about the only one that is usable. I wouldn't use the Barlow at all.

There is a good website full of info about this HERE

Posted on Dec 31, 2010


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and here is a link showing diagonals:

Measure the hole in the telescope and buy the correct size diagonal.

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1 Answer

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Hiya...ALL factory-installed rearview mirrors are installed with different wires due to options.
About 6 different rearview mirrors are installed with those options such as On-Star, light, compass, and those features which use different wires....THIS CANNOT be modified with different rearview mirror....**for example, the Equinox owner attempt to pull out a factory-installed base rearview mirror and put in different one that has compass/temperature built into the rearview mirror**

However, the wires are located inside the front headliner which requires removing the sunvisor (and possible removal of interior plastic trim part at the left/right ends of the windshield) prior to pull the headliner down, and a small metal philips or torx screw is used to secure the rearview mirror onto the bracket glued to the windshield.

The best solution is to leave the original factory-installed rearview mirror in place.

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