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GrassLakeRon
March 6th, 2023, 05:33 PM
Hi all,

Yes I am the newbie to this forum, but I have been observing for 30+ years. Im in the market for new eyepieces for my two new scopes. The first(travel scope) is a 6" classical Cass and the second is a 16" dob. My skies are Bortle 2-4 where i normally view. Seeing is Good to Poor (pick a night). I would like "big views" with my dob, but would also like them to work well with my 6. Money is not an issue.

So my question: What would you buy for the dob for deep sky viewing, given my background statement?

I have started my research. I have started looking at the APM UXA line and the Televue Ethos. I have read that the nagler line is on its way out to make way for the delos. Thank you for your time and advice in this matter.

Ron

Howard B
March 7th, 2023, 04:20 AM
Hi Ron,

As a suggestion, I recommend looking into the Nikon NAV-17 HW 102 degree eyepieces. They offer a 17mm and a 12.5mm version, and each comes with a small, screw-on barlow that transforms them into a 14mm and a 10mm respectively. Expensive, but then you're essentially getting two eyepieces for the price. More importantly, at least in my opinion, at least the 17mm is slightly better all around than the TeleVue Ethos 17mm. I haven't tried the 12.5mm yet.

https://agenaastro.com/nikon-2-nav-17-hw-eyepiece-17mm-eic-14.html
https://agenaastro.com/nikon-1-25-2-nav-12-5-hw-eyepiece-12-5mm-eic-10.html

GrassLakeRon
March 7th, 2023, 11:23 AM
Thank you I will look into them.

wvreeven
March 7th, 2023, 12:14 PM
in my opinion, at least the 17mm is slightly better all around than the TeleVue Ethos 17mm

Howard, in what way is it better than the Ethos? Sharper, more light, less coma on the edges? What telescope did you test this with? Was that with your 30" F/2.7?

Don Pensack
March 12th, 2023, 02:55 PM
I suggest you log into the CloudyNights.com Forums and go to the Eyepieces sub-Forum, where you will get a hundred + answers right away.
The reason is because over 1700 different eyepieces are available to buy and the answer to your question is not an easy one.
Here is the Buyer's Guide for you to download. It is sortable:
https://www.cloudynights.com/topic/862337-2023-eyepiece-buyers-guide/

Even a very short list of recommendations would have to ask the questions:
What is the f/ratio of your scope?
Do you wear glasses at the eyepiece?
What is your previous experience with eyepieces? Have you used 100° eyepieces?
Do you prefer low powers or high powers? What objects do you like to view?
Do you use a coma corrector in the 16" dob?
The answers would change the recommendations.

Since the answers might result in some complicated answers, I suggest CloudyNights.com to keep this forum from becoming a hardware-oriented forum.
I know the members may not mind, but there are no right or wrong answers to your question.
If money is not an issue, then why not engage in a process of experimentation?

Coma is an aberration found in all newtonian telescopes. It is fairly rare that an eyepiece have any visible inherent coma. If coma bothers you, use a coma corrector and it will cease to be a problem.
Astigmatism in eyepieces is a different story, and many eyepieces that are usable at f/10 behave poorly at f/4, which is why the f/ratio of the scope is important.

If you prefer to not log in to CloudyNights.com, you can send me an email and we can carry on a conversation about it. I field 100+ similar questions every day of the week.
My email is Don@EyepiecesEtc.com
It's not clear yet just how to answer your questions.

GrassLakeRon
March 13th, 2023, 03:36 PM
Since the answers might result in some complicated answers, I suggest CloudyNights.com to keep this forum from becoming a hardware-oriented forum.
I know the members may not mind, but there are no right or wrong answers to your question.

I did get that feeling here. Newbie mistake. I wish our local club was still around. I was past president for a long time. We weren't getting any younger and it seemed the next generation didn't want to look at the stars. The other local clubs don't spend the money on high end eyepieces, which is fine, but It doesn't give me an opportunity to check out the new eyepieces or at least those from the last 20 years. My last go around was a type 1 Nagler in a 20" obsession 20 years ago. A lot has changed.

Howard B
March 14th, 2023, 05:12 AM
Howard, in what way is it better than the Ethos? Sharper, more light, less coma on the edges? What telescope did you test this with? Was that with your 30" F/2.7?

Yes, yes, and yes! I compared my Ethos 17mm to the Nikon 17mm for several months, using the same Paracorr 2 with both eyepieces. The first night told the tale though - slightly more contrast and slightly sharper stars at the edge. I did the comparison with the 30-inch f/2.7.

A final note - the Nikon is a bit heavier than the Ethos, and has funky, but functional dust caps.

GrassLakeRon
April 5th, 2023, 04:29 PM
I took the plunge and ordered the APM XWA 13,9,7,4.8 from Don (Absolutely would recommend ordering from him!) They just showed up in time for 2 days of rain, but clear skies for 5 days after that. I will first try them in my 6" Classic Cass as I am still waiting on my new dob.

Don Pensack
April 5th, 2023, 06:00 PM
I took the plunge and ordered the APM XWA 13,9,7,4.8 from Don (Absolutely would recommend ordering from him!) They just showed up in time for 2 days of rain, but clear skies for 5 days after that. I will first try them in my 6" Classic Cass as I am still waiting on my new dob.

Astronomy equipment emits moiston particles, around which water condenses into opaque droplets called clouds.
Only the light of the Full Moon is capable of burning through these moiston particles and clearing the sky.
That's why it's cloudy at New Moon and clear at Full Moon, in case you wondered.:D

GrassLakeRon
April 6th, 2023, 10:38 AM
Astronomy equipment emits moiston particles, around which water condenses into opaque droplets called clouds.
Only the light of the Full Moon is capable of burning through these moiston particles and clearing the sky.
That's why it's cloudy at New Moon and clear at Full Moon, in case you wondered.:D

See, I was hoping you were going to invent an H2O filter for just that problem........