There are a couple eyepiece lines that Celestron currently makes that are designed for use in SCT's. In Schmidt Cassegrains they work brilliantly, but placed in other telescope optical designs, like a Newt, and they are poor performers. No flaw in the eyepiece, just not an optical match. This is like the Baader Hyperions - great in SCT's (for which they are designed for) but poor in any other scope.
These are the Ultima LX line and the Luminos. I have the 8mm and 13mm Ultima LX eyepieces. Brilliant in my C8. The 8mm is particularly easy on the eye - I love using it while doing my Lunar sketches as it gives me the least amount of eyestrain. But both are useless in my fast Newtonians.
Nothing wrong with the Luminos either. Yes they are made in a different factory from the discontinued Axiom, but they are a different design to the Axiom - nothing to do with the manufacturer being different. Some of the old Axiom LX line were great across different types of scopes. The 31mm and 23mm are really good in Newt's. But Celestron does not make large Newt's anymore. They can concentrate on making their premium line of eyepieces for SCT's that way.
We expect every single eyepiece to perform exactly the same from a refractor to Newtonian to SCT to Mak. But we forget that these are all distinct optical designs, all with different shaped focal planes, and with a great range of focal ratios between each adding to the complexity. It is also the same for eyepieces that they will also be differences between them, and different ones will be best suited to different optical systems of scope's. Few are the designs that will do well in ALL systems, and even within an eyepiece line, there will be performance difference - there has to be. Unfortunately manufactures DON'T tell us these things, for fear that their products would be seen as faulty. We as consumers get it in the neck when we purchase an eyepiece, stick it in a scope, and are disappointed with the resulting image. Just as bad though, we then proceed to write off this eyepiece as crap, when we haven't matched the EP to the scope.
The Ultima LX line can be had from the States from around US$100. If all you have is an SCT, then these are a good eyepiece for your scope. You will find the 32mm will do well in your C9.25.
Focal reducers are designed for photographic applications. They do not do well with eyepieces as a whole (there will be exceptions). Don't forget, reducer-come-correctors will by definition alter the shape of the focal plane of the outgoing light cone from the initial one, to suit an SCT with its inherent aberrations. Eyepieces are not designed to handle this change, so the resulting image is poor - nothing to do with having a crap eyepiece. Your Hirsch reducer is the exact same one that Celestron and Meade sell for five times the price! Nothing wrong with the reducer. Everything wrong with what you are expecting the reducer to do for you.
Mental.
Last edited by mental4astro; 28-03-2014 at 07:46 AM.
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