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Lens help please


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Hello everyone. 
 

ive just been gifted a Celestron powerseeker 127eq. It came with two 20mm lenses and one 10mm lens. 
 

i haven’t managed to use it yet as it’s pretty cloudy. 
 

I’d love to be able to see Saturn and perhaps Jupiter. I’m unsure what lenses I need? 
 

I’ve read a lot about a Barlow lens? 
 

If anyone could shed any light. Thanks :)

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Hi there. Congratulations on your gift, now all you need are a few dark nights 🙂.

I believe that the Celestron Powerseeker has a focal length of 1000mm. This means that you'll get x50 magnification with the 20mm eyepieces and x100 with the 10mm.

You'll see the larger planets, but perhaps not as big as you'd like in the view. Typically, you'd want x200 magnification to get a really good look at Saturn. 

This is where a Barlow Lens can come in handy. These effectively multiply the focal length of the scope by the amount in its description - a x2 Barlow multiplies the f.l. by 2, so you'd get x200 magnification with your 10mm eyepiece and a x2 Barlow.

However, with Barlows, the more you pay, generally the better you get. 

The same is true for eyepieces, so if yours are just stock eyepieces, you might benefit from getting better ones before you invest in a Barlow. 

Hope this helps. 

 

Mike

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2 hours ago, Jjmorris90 said:

Hello everyone. 
ive just been gifted a Celestron powerseeker 127eq. It came with two 20mm lenses and one 10mm lens. 
i haven’t managed to use it yet as it’s pretty cloudy. 
I’d love to be able to see Saturn and perhaps Jupiter. I’m unsure what lenses I need? 
I’ve read a lot about a Barlow lens? 
If anyone could shed any light. Thanks :)

The oculars ("eyepieces") you have are fine.  A Barlow lens will not do much for you right now. You have to learn how to use the telescope. It will show you much beyond Jupiter and Saturn, as stunning as they are. With Orion rising now in the evening, you will find that it is loaded with targets, including, of course, the very famous Messier 42 nebula cloud formation in the Sword. Do not rush into magnification or extra gear.  After Christmas, you will find a lot of options for returned gear with reputable retailers such as First Light Optics here. (Where are you located?, if I may ask. See about setting up your user profile and options there.) 

Nothing will look like it does online or television with specials about Hubble Space Telescope images, and all that, but the truth is that you will be doing your own exploring and discovering of Lunar features, the planets, double stars, and open clusters, fuzzy globular clusters, and more. It is your gateway to the Universe.

By the way: Is one of those 20mm eyepieces a "correcting" image? The way to know is to look at the Moon. The shiny side will point to the Sun of course. However, because in space, there is no up or down, most of our eyepieces do not correct for orientation. In fact, if you look at maps of the Moon often you will see South at the top.

This website will help you plan for viewing Jupiter:

https://skyandtelescope.org/wp-content/plugins/observing-tools/jupiter_moons/jupiter.html

And this one for Saturn:

https://skyandtelescope.org/wp-content/plugins/observing-tools/saturn_moons/saturn.html

Note that they give you options for three views. You want the Inverted: Newtonian/Dobsonian when you are in the "native" mode. If one of the 20mm is a correcting lens, then you want the Direct view.

1 hour ago, Stickey said:

Hi there. Congratulations on your gift, now all you need are a few dark nights 🙂.

You'll see the larger planets, but perhaps not as big as you'd like in the view. Typically, you'd want x200 magnification to get a really good look at Saturn. 

Mike

I have to disagree, Mike. The Celestron PowerSeeker 127EQ is an excellent telescope at 40 to 100X. Our new friend has 20mm and 10mm oculars and 50X to 100X is perfect for it. This is also a German Equatorial Mount. So, learning to use that is also a bit of a challenge. jjmorris90 will have to find out for himself about inverting the telescope when he crosses the meridian. 

Myself, when I started with my Celestron AstroMaster 130EQ, I also bought the Celestron lens and filter kit. It is a great toolbox. I bought it because I saw people at star parties with huge telescopes refractors and reflectors both and the same Celeston kit.  I am still happy with it after seven years and I am now spending as much on single eyepieces as the kit cost back then. That said, though, I did not get any use from it for the first 10 or 12 times I went out with my telescope. In fact, I was disappointed with it. I only learned to appreciate it after I learned to use the telescope well with its "native" equipment, the 20mm and 10mm eyepieces.

Best Regards,

Mike M.

Edited by mikemarotta
fixes
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Thank you for the replies. 
 

you’re right, for now I will focus on learning how to use the telescope. It looks ever so complicated. Wish me luck lol. 
 

im in the East Midlands. In a Little village which is pitch black at night.  
 

just waiting for a clear night now. 
 

il check out the moon later and see if one of the pieces is correcting. 
 

thanks!

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Hiya and welcome aboard SGL.

While you're waiting for a dark night, I'd recommend having a play with your new telescope during daylight.

First have a go at focusing the main telescope. Put your largest eyepiece in and point the scope at something distant (1/2 a mile or so if possible), chimney pots, aerials etc are all good targets. Astronomical telescopes don't often focus on close objects. Play with the focuser until you get a sharp image. It may be upside down or left/right inverted, but that's fine. There is no up/down in space.

Once you've got the hang of focusing with different eyepieces and moving the scope around, have a go at setting up the finder scope. That's the small telescope that probably sits on top of the main one. Both the finder and the main telescope tube have to point to exactly the same thing, otherwise you won't be able to find anything. With the main telescope pointing at something familiar, look through the finder and adjust the screws until it also points to the same thing. For extra points get them both smack bang in the middle with your smallest eyepiece.

Now you've got that set up, the way to operate the scope is to use the small finder scope (which gives a larger field of view), to aim the whole instrument. Have a play.

Get used to finding all the bits, putting it together and taking it apart... before trying it in the dark.

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If using your telescope during the day be very careful not to point anywhere near the sun. 

The planets are quite low in the sky so you may find they do not resolve very well as you would be looking at them through a lot of atmosphere. Stellarium is a great planetarium to use to find where different objects are.

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Hi @Jjmorris90 and welcome to SGL. :hello2:

22 minutes ago, happy-kat said:

If using your telescope during the day be very careful not to point anywhere near the sun. 

The planets are quite low in the sky so you may find they do not resolve very well as you would be looking at them through a lot of atmosphere. Stellarium is a great planetarium to use to find where different objects are.

I have a version running [plus a few other astronomy apps] on an old Apple iBook G4... PPC... not Intel processor. :hiding:

And the best thing about Stellarium for PC/Mac/Linux is that it is FREE! :thumbsup:

 

Edited by Philip R
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I think your scope has a focal length of 1000mm so the 6mm will give you a useful 167x magnification. The 2x barlow with the 10mm eyepiece will give you 200x which will probably be the maximum useful most of the time. With the 20mm eyepiece the 3x barlow will give 150x which will be useful as well but it's quite close to the 6mm eyepiece on it's own. Using the 3x barlow with the 10mm or 6mm eyepieces will deliver more magnification than is effective I think.

A 32mm eyepiece would be useful to give a lower magnification and show more sky - useful for deep sky object observing.

You have a nice neighbour :smiley:

 

 

Edited by John
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For now I'd steer clear of trying to take pictures through your new scope and just learn how to use it visually. Most stars should appear as pinprick of light unless you're looking at one of the big ones like sirius or beleguese. If your stars are blobby as above when you're simply viewing them then they are out of focus. 

Once you've got used to the scope and figured out what you're looking at and how to get that object focussed properly, get hold of a decent mobile phone bracket to ensure your pictures are as vibration free as possible.

graeme

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