Celestron prism diagonal any good?

[Ags]

I am looking to get a prism diagonal, and this one is pretty cheap:

https://www.teleskop-express.de/shop/product_info.php/info/p2484_Celestron-1-25--90--diagonal-prism-for-refractors-and-cassegrains.html

Is it a case of you get what you pay for?

[John]

Yes, you get what you pay for. It works OK but it's not a Baader T2 !

[celestron8g8]

If it's the actual original one made by celestron then it's good unless your into spending highend dollars for something that may or may not show much of any difference . But if you want to go a little better but not max amount you could buy a Celestron 2" diagonal which has adapter for both 2" and 1.25" EPs' . I have the original 1.25" that came on my C8 from 1997 and in 2010 I bought the 2" diagonal which has the XLT coatings . Honestly I cannot tell the difference  in the prism . But it also depends what EPs' you have . If you have high $$$ EPs' then you should match the glass with likewise diagonals .

https://www.celestron.com/products/2in-mirror-diagonal-with-xlt-coatings

[Louis D]

16 hours ago, celestron8g8 said:

Honestly I cannot tell the difference  in the prism

 The Celestron XLT to which you linked is a mirror diagonal, not a prism diagonal.  Is the 1.25" diagonal that came with your C8 also a mirror as opposed to a prism diagonal?

[celestron8g8]

4 hours ago, Louis D said:

 The Celestron XLT to which you linked is a mirror diagonal, not a prism diagonal.  Is the 1.25" diagonal that came with your C8 also a mirror as opposed to a prism diagonal?

No the one that came with my C8 new was a prism . The 2" diagonal now that Celestron has is mirrored

[Highburymark]

I really didn't like the two Celestron prisms I've had - stock units bought 4 and 2 years ago - upgrading to decent dielectrics and Baader prism made a significant difference in brightness and contrast

[Ags]

Still thinking about this and googling lead me back to my own long-forgotten thread! I am stuck in an infinite loop of confusion...

I am curious about how a prism diagonal can influence spherical and chromatic aberrations, not necessarily for the worse! So I have picked one up to try. I could have got a Tak, but they use lower dispersion glass which isn't what I want in this case - I want the non-neglible impact on aberrations.

I do have a nice dielectric too, so curious how this will stack up.

[badhex]

Hi Ags, I actually could have sent you one for the postage costs as we're both on the mainland. I got one with my C5 but I'm not really a fan. 

[Ags]

PM'd you @badhex!