6 replies to this topic

[twist]

Hello everyone. I currently have a Sky-Watcher Virtuoso GTi 150 f/5 that I've had for a year. I am now upgrading to a 10" Celestron starsense explorer f/4.7, (getting a great deal on the telescope). My 6" scope works well with 60 degree field of view eyepieces. Since the 10" is a different piece of equipment, I am trying to understand the right eyepieces for the 10". So my question is: can I use some of the eyepieces I use in the 6" telescope in the 10"? Is 70 to 80 degree field of view going to work better with the 10"?

[CHASLX200]

Hello everyone. I currently have a Sky-Watcher Virtuoso GTi 150 f/5 that I've had for a year. I am now upgrading to a 10" Celestron starsense explorer f/4.7, (getting a great deal on the telescope). My 6" scope works well with 60 degree field of view eyepieces. Since the 10" is a different piece of equipment, I am trying to understand the right eyepieces for the 10". So my question is: can I use some of the eyepieces I use in the 6" telescope in the 10"? Is 70 to 80 degree field of view going to work better with the 10"?

More coma at F/4.7. Needs a Paracorr.

[twist]

More coma at F/4.7. Needs a Paracorr.

Do I need a paracorr or coma corrector, are they the same thing, and do I need it if I'm not photographing?

[CHASLX200]

Do I need a paracorr or coma corrector, are they the same thing, and do I need it if I'm not photographing?

Well if you don't notice coma you don't need it. It is the same thing.

[Jim T]

Coma is the reason that 'fast' Newtonians historically 'stopped' at f/4.5. Most people can tolerate it to that point, some just cannot. If you love wide fields, clean to the edges, you'll want a Coma Corrector. The Paracorr is arguably the best. My experience is that I'd rather tolerate a soft outer 10% of the FOV than to add the extra weight. The only time coma has truly bugged me was when trying to find (star hop to) tiny Planetary nebula with a 30mm 82*. Doubt you'd ever notice it with an 18mm e.p. or less. Top-end eyepieces help reduce coma slightly.

In my opinion the larger scope will naturally have more magnification, thus you will appreciate ultra-wide eyepieces with it. You can certainly use what you have. I use my 10" f/6 for Outreach, so not using my best eyepieces but for my 10" my stable includes: 26mm Plossl (a 30mm would be better), a 17mm Plossl, a 14mm 82* ES, and a 7mm 82* ES. The 26 and 14 get the most use. I also have a cheap 30mm 80* 2" e.p. for it but it really doesn't see much use for Outreach. I only mention it as it would be a good entry-level "finder" e.p. for non-Outreach in darker skies, but an E.S. or T.V. would be nicer.

Edited by Jim T, 23 March 2025 - 06:32 PM.

[vtornado]

The biggest difference is the difference in focal length  750 vs 1200.    A 10mm eyepiece is 75x in your current scope and will be 120x in the new one.  For my eyes with my 10 inch f/5 I can see the coma in 2 inch eyepieces with a large field stop.   But it is an abberation I can deal with.  Your opinions may be different.   I would use your new scope and see what you think.

 

I don't find any magic in 80 degree+ eyepieces.  You might try one and personally see what you think.  I believe the astro-tech 80 degree line is well thought of an quite economical.  But ... I haven't tried one.

Edited by vtornado, 23 March 2025 - 07:02 PM.

[Jon Isaacs]

Do I need a paracorr or coma corrector, are they the same thing, and do I need it if I'm not photographing?

 

A Paracorr is the name for TeleVue coma correctors.  The first Paracorr was introduced in 1989 and has been improved since them.  I have the latest version, the Paracorr 2, as well as the very first version, the photo-visual Paracorr.  The Paracorr's are the most transparent in use, the least fiddly and the Paracorr 2 has the best coma correction.

 

That said, coma correctors are nice to have but they are not necessary.  I have a 10 inch F/5 Dob, I use a Paracorr because I also have faster Dobs, I have had my 12.5 inch F/4.06 for 25 years.. 

 

But I sometimes use my 10 inch F/5 with the 60 degree Astro-Tech Paradigms and no coma corrector just for simplicity. The views are good.. Not perfect but good.  

 

You are in the process of getting a wonderful new scope.. You are going to enjoy it. It'll work fine with your current eyepieces.  At some point you may want to upgrade your eyepiece collection.. Or not.

 

Jon