Author Topic: I want to see planets better. What eyepieces should I get?  (Read 210 times)

chionewssesu

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Re: I want to see planets better. What eyepieces should I get?
« Reply #15 on: January 18, 2018, 07:35:39 AM »
I want to thank those who have contributed to this thread. I never cease to be amazed when I see the altruism and generosity of so many people who take the time and trouble to give good advice to others. It's what makes the world go round in this and other free forums.

THANK YOU!

teirazaro

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Re: I want to see planets better. What eyepieces should I get?
« Reply #16 on: January 20, 2018, 01:15:05 PM »
Quote
Quote

26mm Meade came with etc 125
9.7mm " "
9.4mm spears Waller I bought
I also have a 2 x barlow

zoom ep? What is a must have ep?

What is your budget? Do you wear eyeglasses when observing?
My budget is not a concern. I wear contacts.

Joel Hall

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Re: I want to see planets better. What eyepieces should I get?
« Reply #17 on: January 22, 2018, 08:48:38 PM »
Quote
Magnification = (Focal Length of your telescope) / (Focal Length of your eyepiece)

You can use the interactive Stelvision "Telescope Simulator" http://www.stelvisio...lator/index.php to see what the Moon, planets, star clusters, etc. look like with your telescope+eyepiece combination. Be sure to click on the "Detailed Simulation -- Choose Your Eyepieces" option to see what your eyepiece views will be like.

Your Meade ETX 125 https://www.meade.co...erver-html.html has a Focal Length of 1900mm. The magnification that is achieved with those two eyepieces is:

For 26mm Super Plossl eyepiece, Magnification = (1900mm)/(26mm) = 73x
For 9.7mm Super Plossl eyepiece, Magnification = (1900mm)/(9.7mm) = 196x

The 2x Barlow Lens has the effect of doubling the Focal Length of your telescope, so with those two eyepieces, the 2x Barlow Lens would give you (2)x(73)= 146x and (2)x(196) = 392x, respectively.

Wow!!!! Love it. Thank you.

ryarejalo

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Re: I want to see planets better. What eyepieces should I get?
« Reply #18 on: January 23, 2018, 12:54:34 PM »
Thank you everyone. This info was incredible. I understand a lot today with this. One question. Is getting a 3 x Barlow? I'm keeping in mind the max I should stay under.

James Bagby

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Re: I want to see planets better. What eyepieces should I get?
« Reply #19 on: January 23, 2018, 04:06:04 PM »
With those two eyepieces (26mm and 9.7mm) that you already have, a 3x Barlow Lens would give you (3)x(73)= 219x and (3)x(196) = 588x, respectively. 588x is WAY TO MUCH magnification and your image will look like this: http://www.rocketrob...ges/sat_lmh.jpg

ringnasingsimb

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Re: I want to see planets better. What eyepieces should I get?
« Reply #20 on: January 25, 2018, 01:07:32 PM »
A 3X barlow for that scope would be wasted. You would not use it.

The purpose of a barlow is to create a second magnification for each eyepiece which reduces the number of eyepieces you need.  It also allows you to use longer FL eyepieces for higher powers where the shorter FL eyepieces may have short eye relief.

For example.

A 20 mm Meade 4000 Plossl eyepiece has about 15 mm of eye relief - comfortable for most people and useable with glasses.

A 9.7 mm Meade 4000 Plossl eyepiece has about 6 mm of eye relief - many people feel this is a bit tight and you would not use it with glasses.

So they can barlow the 20 mm to 10 mm for about the same magnification and still have 15 mm of eye relief. - That is the second value of the barlow.You have a 26 mm and 9.7 mm eyepiece and a 2X barlow.  So you have the equivalent of 26, 13, 9.7 and 4.7 mm eyepieces.

1900/9.7 = 196X - On many nights that will be about as high as you can go due to atmospheric conditions.

Using a 2X barlow - 1900/4.7 = 404X  WAY too high power for your telescope and atmospheric limitations.

So, what would be the value of a 3X barlow?

That would give you the equivalent of a 3.2 mm eyepiece for 593X.  Way Way to high for your telescope. A 3X would be wasted.

I don't even use a 2X barlow with my ETX 125. My 24 to 8 zoom takes me to 237X which is about as high as this scope will go even under very good conditions.  I use 2X and 3X barlows on my other scopes, but not this one. The focal length is so long that there is no need for a barlow.

If you want to get a 7-8 mm eyepiece for your scope, that would be good.

Or you get a 16 mm eyepiece and use your 2X barlow to get the equivalent of 8 which would be good.  16 mm would be a nice midrange for that scope for 119X, a very useful magnification.  With the 2X barlow you would be 238X. Right about the limit of the practical range of this scope. On an exceptional you would be able to use it on the planets and the moon.

That would give you 26 mm, 16 mm 13 mm, 9.7 mm 8 mm 4.7 mm.   

Remember it is the atmosphere that is creating the limitations once you get past 200X

No 3X barlow for that scope.

Jay Garcia

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Re: I want to see planets better. What eyepieces should I get?
« Reply #21 on: January 25, 2018, 08:49:19 PM »
Quote
Quote

Quote

26mm Meade came with etc 125
9.7mm " "
9.4mm spears Waller I bought
I also have a 2 x barlow

zoom ep? What is a must have ep?

What is your budget? Do you wear eyeglasses when observing?
My budget is not a concern. I wear contacts.
If budget is not a concern then see my post, #11

Get the Baader Hyperion 24-8 zoom and you have everything you need for that scope in a high quality eyepiece and wider views than your Plossls over most of the range.
http://agenaastro.co...ce-2454826.html

Add a 32 mm Plossl for low power wider view -
http://agenaastro.co...l-eyepiece.htmlSave the 2X barlow for playing at high magnifications, over 237X, when conditions are exceptional.  It can be fun to try 400X on the moon on a clear night. You can push the Moon higher than the other planets.  It is fun but the image will likely shimmer in and out of focus like you are looking through boiling water. 

Retire the 26 and the 9.7. You won't need them.

Baader Hyperian Mark III Clickstop zoom review – About $280
I have an older model Baader Hyperion, but I find the review accurately reflects my experience.
The current model is the Mark IV.http://www.weasner.c...iece/index.html

Baader Hyperion Mark IV - The current modelhttps://www.cloudyni...-zoom-eyepiece/

Baader Zoom Vs Fixed Eyepieces -http://www.cloudynig...m-vs-fixed-eps/Edit:  Note that I do have other eyepieces that I can use in this scope.  I have Explore Scientific 82 8.8 and 6.7. Meade 5000 SWA 5.5 and HD60 4.5 I also have a selection of Plossls, 32, 26, 25, 18 12.5, 10, 9.7, 8 and 6 mm.  So I have those available if I were to feel they were going to provide a better image than the zoom. When I was using mostly the Celestron Zoom I would swap them in from time to time.  I rarely use them now, since getting the Baader Hyperion Zoom.

miswalltile

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Re: I want to see planets better. What eyepieces should I get?
« Reply #22 on: January 25, 2018, 11:26:31 PM »
I'm a big fan of University Optics Orthos for Planetary viewing. For any scope. They still pop up on the CN Classifieds, so get 'em if you can.

STARKID2U

James Bagby

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Re: I want to see planets better. What eyepieces should I get?
« Reply #23 on: January 30, 2018, 11:23:45 PM »
Quote
Thank you everyone. This info was incredible. I understand a lot today with this. One question. Is getting a 3 x Barlow? I'm keeping in mind the max I should stay under.

What I did was to get a 2X, and a 3X Barlow.
My first summer with my Telescope, I was able to bring up Saturn. Then added the 2X and adjusted. The tried the 3X and adjusted.
But when I stacked both, it really WOWed the crowd.

If you have them, you don't have to use them.
But if you don't have them, you can't even try it.

grumepinod

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Re: I want to see planets better. What eyepieces should I get?
« Reply #24 on: January 31, 2018, 05:17:43 AM »
SonnyE,

I will note that you signature says you are using an Orion ED80T, 480 mm FL.  At 3X that would be like it was 1440 mm FL.  If you stacked a 2X barlow on top of that it would take you to 2880 mm FL equivalent.

Remaxman's scope is 1900 mm FL before using a barlow. With a 2X barlow it would take him to 3800 mm equivalent.  A 3X barlow would take his scope to the equivalent of a 5700 mm FL.

Just providing some context.  Your experience would be very different from what he would see.

James Bagby

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Re: I want to see planets better. What eyepieces should I get?
« Reply #25 on: January 31, 2018, 01:23:36 PM »
Quote
26mm Meade came with etc 125
9.7mm " "
9.4mm spears Waller I bought
I also have a 2 x barlow

zoom ep? What is a must have ep?

I just went through the whole discussion. I don't think you ever told us what was wrong with the view you had of the planets now.

We have been focused on magnification, as that is usually what needs to be boosted.

However, that may not be your concern since you do have a 2X barlow.

If we could wave the magic wand, how would we improve your planetary views?
Size
brightness?
image shimmer?
Won't hold focus?
Glow?
Color?
What are we trying to fix?

( should have asked this in my first post.  )

Edit: also what is your light pollution like, in the sky and on the ground.

James Etrheim

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Re: I want to see planets better. What eyepieces should I get?
« Reply #26 on: February 02, 2018, 03:30:07 PM »
I have that scope and usually don't go any higher than 165x with a 12mm eyepiece. But, if you get a really great seeing night and the planets are higher than 25* over the horizon, 200x would be ok. Don't try to observe them over buildings that give off heat ect.

Also, a dew shield is a must for that scope, also blocks stray light from hitting the front lens.

Larry Hopkins

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Re: I want to see planets better. What eyepieces should I get?
« Reply #27 on: February 02, 2018, 04:32:08 PM »
I will add ..

How well is you scope Collimated ?

Can you see steady circular diffraction rings
Not just out-of-focus fresnel rings, but diffraction rings.

If the image from scope is terrible, then no amount of magnification will fix that

tamamatte

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Re: I want to see planets better. What eyepieces should I get?
« Reply #28 on: February 02, 2018, 07:50:12 PM »
Its a great planetary scope but only 125 I dont think its out of collimation but a 125 will only give 150x generally so your eyepieces are fine DONT SPEND MORE get a bigger scope

Rahul Sanders

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Re: I want to see planets better. What eyepieces should I get?
« Reply #29 on: February 02, 2018, 09:47:33 PM »
Quote
SonnyE,

I will note that you signature says you are using an Orion ED80T, 480 mm FL.  At 3X that would be like it was 1440 mm FL.  If you stacked a 2X barlow on top of that it would take you to 2880 mm FL equivalent.

Remaxman's scope is 1900 mm FL before using a barlow. With a 2X barlow it would take him to 3800 mm equivalent.  A 3X barlow would take his scope to the equivalent of a 5700 mm FL.

Just providing some context.  Your experience would be very different from what he would see.

My experiences are very different from anybodies.
I'm an imager. I have a smattering of Optical's. But not my primary interest. They were tools for my learning curve.
Nor do I care about the math, only my results.
As a retired old fart, I'm primarily out there to enjoy myself.
It still stands that if one has options, they could try them. Stacking my Barlow's, although bottom end, sure gave the family a thrill with their first live view of Saturn.
Made a warm memory. And truly, none complained about image degradation. I noticed it, but none of them did.

But my primary interest is pulling down Nebula images. Hence, my choice of a telescope well suited to that end.
I knew my goal, before I ordered anything.

And as Paul Harvey used to say, "And now you know.... the rest of the Story. Good Day."