Posted 22 April 2013 - 09:30 AM
Could anyone give me an explanation of what is a Celestron CPC with Hyperstar?
Thanks in advance, Fernando
Posted 22 April 2013 - 10:02 AM
Years ago Celestron released some of their SCTs with a removable secondary mirror, they called this Fastar compatibility. They also released a special lens assembly called Fastar that would mount in the spot where the secondary mirror was originally installed. The actual Fastar product didn't last very long but they kept on making SCTs with the Fastar compatible secondary. One of the Celestron dealers (Starizona) then produced an upgraded version of the Fastar lens assembly, they call it Hyperstar. The Hyperstar lens can be attached to any Fastar compatible SCT and sometimes folks will also describe a scope as Hyperstar compatible.
A "CPC with Hyperstar" would be a scope with the removable secondary mirror and have that Hyperstar lens product included with it. If you were buying a scope advertised like this I would be careful that the selling actually is including the Hyperstar lens and is not just verifying that the scope is Hyperstar compatible. If you have no interest in the Hyperstar lens product you can safely ignore the compatibility statement, it makes no impact on how you use the scope in a traditional fashion (either visually or imaging).
Information on Hyperstar - http://starizona.com...star/index.aspx
Posted 22 April 2013 - 11:16 PM
As Mark pointed out, a CPC that is "Hyperstar-ready" would have a removable secondary which can happen two ways: either the CPC came from the factory with a Fastar secondary already installed, or an "ordinary" CPC could be outfit with a Hyperstar kit from Starizona. All HD Edge scopes and more and more of the CPC lineup come with Fastar already installed.
Either way, to actually mount a camera and shoot, you would have to get a Hyperstar lens from Starizona, remove your Nexter and replace the secondary with it. When you do so, your scope becomes a quite fast f/2.0 scope ready to take photos ith 1/30th the amount of time as a CPC without hyperstar. (Rather than an f/10 .
I just ordered a hyperstar for my CPC1100 today. My CPC came with the Fastar secondary from the factory.
Jim in Boulder
Posted 23 April 2013 - 05:14 AM
How ease it is (and safe for the optics) to install (down to f/2. Really?) and back to f10. Or there is no need, given that the aperture will not change? You may use it for observing and imaging. That is the basic idea, right? I took a look on Starizona and they have a step-by-step tutorial for installing the Hyperstar. As I am in Brasil I have to be careful buying and modifing a telescope.
My CPC800 came with the Faster from factory. As I am planning to upgrade to a CPC1100, I will wait.
Posted 23 April 2013 - 06:07 PM
However, the Hyperstar is ONLY for photography. The Hyperstar lens replaces your secondary mirror and the camera attaches on the front of the Hyperstar which is now on the front of your scope. No light is reflected back through to the eyepiece. In fact, you remove your eyepiece diagonal too and replace it with a weight to balance the scope with the lens and camera hanging off the front.
So, you get f/2 for photography only. And you stay at f/10 for visual (and of course photography, the old fashioned way).
The way an SCT works is that the main mirror is a very fast f/2. But the secondary is located just short of the focal point of the mirror and is curved (convex) to reflect the light back through the mirror cutout with 5x magnification giving you a net system speed of f/10.
Removing the secondary places the Hyperstar right at the f/2 point in the optical path. The Hyperstar is there to correct the spherical aberation coming off the spherical main mirror, normally performed (mostly) by the convex secondary.
Makes any sense?
Jim in Boulder
Posted 24 April 2013 - 08:16 PM
Make lots of sense. Thank you again.
Would love to hear your experience after you have the
hyperstar in your CPC1100.
Posted 29 April 2013 - 02:00 PM
The hyperstar is great system. It is very easy to install and remove - only taking a matter of a minute or so.
The hyperstar comes with a screw on cap which you use to store your secondary mirror while you are using the hyperstar.
Feel free to check out my website for some of my images with the hyperstar here:
Also check out the Hyperstar imaging thread here for much more impressive work done by others here at the forum:
Being F2, it is a very widefield system, so smaller galaxies are captured, but appear very small in the final image. You will likley want to also shoot in the standard setup via the rear port in order to capture the smaller galaxies and planets.
If you are planning on a CPC scope, I can also recommend looking at some modifications that can be made to the scope to allow for better tracking. Here is a link to a series of posts where I outlined my modification and made a video explaining the process:
Best of luck!!