Author Topic: New Eyepieces  (Read 735 times)

rotenoter

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New Eyepieces
« on: December 23, 2017, 11:27:30 PM »
I am sure you get these types of questions a good deal, but allow me to say in advanced, I appreciate the help.  I really should make sure I am making the right purchases.

I have a Celestron 4SE telescope, '' it is a 4" Maksutov, F/13.  It came with a 25mm eyepiece.  However, as I have started to use the telescope, I see that it isn't enough to see either planets or deep sky objects.  I would love to upgrade to a bigger telescope someday, therefore it would be fine if the eyepieces I purchase will work with a bigger reflector.

One of the first objects I found when I purchased my telescope was the butterfly bunch.  It was magnificent, however, I could tell the eyepiece clipped off several stars.
So, I was thinking of purchasing a 32mm Televue Plossl.

I was also thinking of getting the Celestron Ultima 2x Barlow.  I haven't found a lot of reviews on barlow lenses, but it sounds like that is relatively good for the price.  If other people have recommendations I would appreciate it.

I would also prefer to purchase an eyepiece for planetary viewing, such as a 6mm.  But I am not sure which type of eyepiece to purchase, most of the ones I have looked at are over $200.  I was looking at the Baader 6mm Ortho.  I am just not sure.

I would appreciate any help in confirming I am selecting the right eyepieces.



swittetsakee

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Re: New Eyepieces
« Reply #1 on: December 23, 2017, 11:35:29 PM »
I really do believe your range is much more capable than you think.  A four inch range with a 25mm will show you more than you think it will.  Maybe give it another shot ?

retpoiwerround

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Re: New Eyepieces
« Reply #2 on: December 24, 2017, 06:28:10 PM »
To add to what I said, you are Mak is certainly capable of visiting planets.  That is what it's largely designed for.  And the only reason you'd want to go to a lower electricity (32mm) would be to observe DSOs.  Planets demand a mid range of EPs, occasionally higher power, based on atmospheric conditions, seeing, transparency.

Jason Muse

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Re: New Eyepieces
« Reply #3 on: December 28, 2017, 11:44:13 PM »
Another thing I want to add, while barlows will effectively cut your EP needs in half, if you buy in the correct increments, you won't ever need a barlow. I have a 2x barlow , but I have enough EPs that I never use it.

Ryan Hernandez

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Re: New Eyepieces
« Reply #4 on: December 29, 2017, 04:54:30 AM »
At f/13, almost any brand of 32mm Plössl should perform well.

You may want to consider one of the Celestron X-Cel LX, Meade Series 5000 HD-60, Astro-TechParadigm Dual ED, orAgena Starguider Dual ED eyepieces for planetary observing. The first two lines are similar to each other, as are the third and fourth.

https://www.astronom...pieces_c62.aspx

https://www.astronom...pieces_c73.aspx

https://www.astronom...pieces_c52.aspx

A 6mm eyepiece will produce an exit pupil of less than 0.5mm in your telescope. You may want to get a 7 or 8mm instead.

Dave Mitsky

fewithciten

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Re: New Eyepieces
« Reply #5 on: December 30, 2017, 12:37:51 AM »
Welcome to CN, Stargazer.

I'm relatively new myself, and thanks to the advice of more experienced CN members I ended up purchasing several Astro-Tech Paradigm Dual ED EPs, a 12, 18, and 25. The telescope came with a decent 40mm Plossl. The Dual EDs are bargains--I've compared them with premium-priced EPs (on my telescope) and I find it difficult to see a significant difference. With a fast refractor, the differences might be slightly more apparent, but then the price I paid per EP is roughly 1/5 the cost of a Type 6 Nagler. My Nagler-owning friend was truly impressed with the Dual EDs himself. They have good eye relief and decent field of view, which is something Plossls, especially those in shorter focal lengths, lack. I have a Baader 2.25x Barlow, and it's fine, but seldom used.

The Astro-Tech Paradigm Dual EDs are available from Astronomics, but they are also available from Agena under the name of Starguider Dual ED--same EP, same price.  For someone just getting into astronomy the Dual EDs are tough to beat.

inmactoopho

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Re: New Eyepieces
« Reply #6 on: December 30, 2017, 09:07:32 AM »
Quote
Welcome to CN, Stargazer.

I'm relatively new myself, and thanks to the advice of more experienced CN members I ended up purchasing several Astro-Tech Paradigm Dual ED EPs, a 12, 18, and 25. The telescope came with a decent 40mm Plossl. The Dual EDs are bargains--I've compared them with premium-priced EPs (on my telescope) and I find it difficult to see a significant difference. With a fast refractor, the differences might be slightly more apparent, but then the price I paid per EP is roughly 1/5 the cost of a Type 6 Nagler. My Nagler-owning friend was truly impressed with the Dual EDs himself. They have good eye relief and decent field of view, which is something Plossls, especially those in shorter focal lengths, lack. I have a Baader 2.25x Barlow, and it's fine, but seldom used.

The Astro-Tech Paradigm Dual EDs are available from Astronomics, but they are also available from Agena under the name of Starguider Dual ED--same EP, same price.  For someone just getting into astronomy the Dual EDs are tough to beat. 

I'll addmy endorsement. I've used many an eyepiece over the years and these a very good value.

erafquacor

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Re: New Eyepieces
« Reply #7 on: January 03, 2018, 09:18:31 AM »
My first question is about your budget. There are $50 eyepieces and there are $500 eyepieces.

You have named some higher end brands, Tele Vue and Baader for example. Is that your focus or is that simply a brand you heard about?

Do you want to stay with higher end brands, $150+ per eyepiece.

Are you interested in trying out more moderate priced eyepieces, like the Meade Series 5000 HD-60, Explore Scientific 68 and 82 degree in the $60 to $150 range.

Or are you interested in trying lower priced eyepieces that may deliver adequate but not stellar performance.You can spend $300 on one eyepiece or on 5. 

Meade and Orion Plossl eyepieces do a pretty good job for less than $50 each.  I have them.

The HD-60 and ES eyepieces that I have have pleased me greatly.

I have never looked through a Tele Vue or a Baader eyepiece.

ocgisfulctel

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Re: New Eyepieces
« Reply #8 on: January 11, 2018, 10:38:19 AM »
Your telescope has a focal-length of 1325mm...

1325mm ÷ 6mm = 221x, and close to its "Highest Useful Magnification" of 241x, according to Celestron.

http://agenaastro.co...epiece-6mm.html (221x)

http://agenaastro.co...0-eyepiece.html (204x)

http://agenaastro.co...f-eyepiece.html (241x, and right on the money)

An 8" f/6 or 10 F/5 "Dobsonian" would have similar focal-lengths, at 1200mm and 1250mm, respectively.

adrajacte

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Re: New Eyepieces
« Reply #9 on: January 13, 2018, 01:32:34 AM »
The difference being that a 5.5mm eyepiece being used in an f/6 Dob would produce a more reasonable exit pupil of 0.9mm and in an f/5 Dob an exit pupil of 1.1mm. In an f/13 scope, the exit pupil would be 0.4mm.

A 1mm exit pupil gives you maximum planetary detail and is excellent for splitting binary stars. A 0.5mm exit pupil is useful for splitting close double stars, but only during very good seeing.

https://www.astronom...t-pupils_t.aspx

Dave Mitsky

Michael Consumers

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Re: New Eyepieces
« Reply #10 on: January 13, 2018, 03:25:55 AM »
Interestingly, and perhaps wildly-optimistic to boot, Celestron states "15x" as the "Lowest Useful Magnification" to somehow realise with its 4" f/13 Maksutov...

That would require an 88mm ocular, and with a 6.8mm exit-pupil; not impossible however, as I've read of someone having made a 100mm even.

lodbelimfo

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Re: New Eyepieces
« Reply #11 on: January 13, 2018, 06:03:15 AM »
For the lowest magnification, I feel that I made a mistake in acquiring a 40mm Plossl, and went all out and got a Tele Vue even. I'm having to swallow that, and to this day.

I then got a 2" 70° 32mm ocular, and finally saw the light. However, I also wanted a 1.25" 32mm, and to use with my telescopes that have focussers of same. I narrowed it down to two...

http://agenaastro.co...mm-2954132.html
http://agenaastro.co...l-eyepiece.html

A fellow amateur, on another astronomical website, tested both side by side. I then chose accordingly, and couldn't be more pleased...
The slightly-improved performance over the Baader may or may not be attributable to the Vixen's larger eye-lens, but it is impressive nonetheless.


Anthony Graham

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Re: New Eyepieces
« Reply #12 on: January 13, 2018, 09:14:48 AM »
Quote
<p class="citation">QuoteAn 8" f/6 or 10 F/5 "Dobsonian" would have similar focal-lengths, at 1200mm and 1250mm, respectively.

The difference being that a 5.5mm eyepiece being used in an f/6 Dob would produce a more reasonable exit pupil of 0.9mm and in an f/5 Dob an exit pupil of 1.1mm. In an f/13 scope, the exit pupil would be 0.4mm.

A 1mm exit pupil gives you maximum planetary detail and is excellent for splitting binary stars. A 0.5mm exit pupil is useful for splitting close double stars, but only during very good seeing.

https://www.astronom...t-pupils_t.aspx

Dave Mitsky[/quote]

Dave, you speak in terms of exit pupils.  Would it not be just as appropriate to speak in terms of magnification?

Elijah York

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Re: New Eyepieces
« Reply #13 on: January 13, 2018, 10:08:07 AM »
Quote
<p class="citation">QuoteAn 8" f/6 or 10 F/5 "Dobsonian" would have similar focal-lengths, at 1200mm and 1250mm, respectively.

The difference being that a 5.5mm eyepiece being used in an f/6 Dob would produce a more reasonable exit pupil of 0.9mm and in an f/5 Dob an exit pupil of 1.1mm. In an f/13 scope, the exit pupil would be 0.4mm.

A 1mm exit pupil gives you maximum planetary detail and is excellent for splitting binary stars. A 0.5mm exit pupil is useful for splitting close double stars, but only during very good seeing.

https://www.astronom...t-pupils_t.aspx

Dave Mitsky[/quote]
I have to admit that I didn't realize the significance of exit pupil diameter at the time of purchase, but it certainly explains why my 12mm Dual HD is, roughly speaking, the shortest focal length EP I use for the majority of my planetary and DS work with my f/10 SCT. (exit pupil dia. = 1.2mm) I've ordered a Lunt 60mm, f/8 solar telescope, for which I will want some shorter EPs, but for the SCT the 12mm does best under typical (poor to marginal) seeing conditions. Fighting the urge to "power up" has been tough, but experience is the best teacher.

Jeremy George

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Re: New Eyepieces
« Reply #14 on: January 13, 2018, 12:34:44 PM »
Quote
Interestingly, and perhaps wildly-optimistic to boot, Celestron states "15x" as the "Lowest Useful Magnification" to somehow realise with its 4" f/13 Maksutov...

That would require an 88mm ocular, and with a 6.8mm exit-pupil; not impossible however, as I've read of someone having made a 100mm even.

I'm not sure about a mak scope, but if you use too long of a focal length in newt, you can get "ghosting" of the secondary
in the eyepiece. I have an 6" f/5 newt and some eyepieces 40mm and over had this issue. I'm not sure if it has to do with
the huge exit pupil or what?