Author Topic: First Telescope - What eye piece to get/avoid?  (Read 38 times)

Lauro Mason

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First Telescope - What eye piece to get/avoid?
« on: December 25, 2017, 09:54:41 AM »
Hi,???
I got a Celestron Powerseeker 80eq for my children and wish to obtain a nice eyepiece to view the moon and planets as best this extent can perform. . .without breaking the bank.  I understand nothing of the topic beyond all of the perplexing reading I've done.

I am also getting the Omni 40mm 1.25" Plossl.  Is this a horrible choice or will be the testimonials reliable?

Last, I've been in IT for more than 20 years and enjoy tinkering, but I want to get it going fairly quickly without overdoing my normal detail work and forcing my two little girls crazy as they wait to work with it after launching on Christmas morning.  Are there any suggestions for things to prevent that individuals have a tendency to waste time since they set a first-time scope?

I am so excited to use the range with my children.  I've already started plans to construct a viewing system in our back yard and no one knows why.

Thank you for any suggestions or help.



Sam Citadelle

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Re: First Telescope - What eye piece to get/avoid?
« Reply #1 on: December 27, 2017, 01:11:41 PM »
Quote
Hi,

 I bought a Celestron Powerseeker 80eq for my kids and want to get a decent eyepiece to view the moon and planets as best this scope can do...without breaking the bank. I know nothing of the subject beyond all the confusing reading I've done.

I'm also getting the Omni 40mm 1.25" Plossl. Is this a horrible decision or are the reviews reliable?

Lastly, I've been in IT for over 20 years and enjoy tinkering, but I want to get it going fairly quickly without overdoing my typical detail work and driving my 2 little girls crazy as they wait to use it after opening on Christmas morning. Are there any tips for things to avoid that people tend to waste time on as they set a first time scope?

I'm so excited to use the scope with my kids. I've already begun plans to build a viewing platform in our back yard and nobody knows why.

Thanks for any help or suggestions.

Avoid a 40mm 1.25" possil (although I have one).

If you want a 40mm make it a 2" 68-70 AFOV for maximum TFOV.

If you want a 30mm make it a 2" 82 AFOV

Maximum TFOV for a 1.25" would be 24mm 68 AFOV panoptic or equivalent.

ovhercayvic

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Re: First Telescope - What eye piece to get/avoid?
« Reply #2 on: December 27, 2017, 02:47:29 PM »
Quote
Hi,

 I bought a Celestron Powerseeker 80eq for my kids and want to get a decent eyepiece to view the moon and planets as best this scope can do...without breaking the bank. I know nothing of the subject beyond all the confusing reading I've done.

I'm also getting the Omni 40mm 1.25" Plossl. Is this a horrible decision or are the reviews reliable?

Lastly, I've been in IT for over 20 years and enjoy tinkering, but I want to get it going fairly quickly without overdoing my typical detail work and driving my 2 little girls crazy as they wait to use it after opening on Christmas morning. Are there any tips for things to avoid that people tend to waste time on as they set a first time scope?

I'm so excited to use the scope with my kids. I've already begun plans to build a viewing platform in our back yard and nobody knows why.

Thanks for any help or suggestions.

Well since you asked about avoiding wasting time, my advice is that this is not going to be a great first scope.

1. The 80mm aperture is limited compared to larger apertures you can get for less money
2. Equatorial mounts like these are quite flimsy, and very hard to aim the telescope with. They're *especially* cumbersome with long refractors.
3. This scope comes with a cheap, low-grade erecting prism diagonal so it can be used for terrestrial viewing, but this impedes its overall optical quality

For less money, you can buy a more capable, simpler to use telescope:

https://explorescien...ts/fl-n114500tn

1. 114mm aperture vs 80mm aperture will be better for the moon and planets. I own a 114mm telescope and it's also verycapable of seeing deep space stuff.
2. The alt-az mount is FAR simpler to use and aim the telescope with
3. It's $50 less than the PowerSeeker
4. The shorter focal ratio will allow for wider field, low power scanning of the Milky Way

I know that's probably outside the scope of your request, but if possible, I would return the PowerSeeker and buy that Explore Scientific.

An alternative would be the Meade Lightbridge Mini 114 table top dobsonian, or if you're willing to stretch your budget a bit, the Meade Lightbridge Mini 130.

That said, to answer your question within the scope of your request:

Yes, that 40mm Plossl is a good choice. It will give you about 22x power and about a 2 degree field of view. This is as wide as you're going to get with that telescope within a reasonable budget. There are options that provide the same field of view with higher magnification, but they're more expensive than the scope itself! You're definitely going to want a low power, wide field eyepiece to help aim the scope and locate objects, so definitely stick with the 40mm Plossl.

To get more magnification for the moon and planets (when they come around again!), you'll need a shorter focal length eyepiece. For this kind of eyepiece, I do NOT recommend getting a plossl. The shorter the focal length, the shorter the eye relief. And Plossls have a narrow apparent field, so keeping the object in the field of view at high magnification becomes more work. For doing planetary and lunar viewing, you want something that provides good magnification, good eye relief, and a decent FOV.

Unfortunately, the scope is so small that high magnification will produce a fairly dim image.

I would aim for an eyepiece between 10 and 12mm in focal length. An excellent option would be the 12mm Agena Starguider Dual ED. It won't be overly dim, and will provide usable magnification (73x). The eye relief is excellent, and the field of view is wider than a typical Plossl. Best of all it's only $60, so it won't break the bank. Agena Starguiders are also highly regarded. As others on this forum have said, they're not just good for the money, they're just plain good.

For more magnification, you can get the 8mm Agena Starguider ($60 - 110x) or 9mm Orion Expanse ($50 - 98x). Both will be better than a Plossl in terms of eye relief and apparent field.

ardrivunla

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Re: First Telescope - What eye piece to get/avoid?
« Reply #3 on: January 01, 2018, 12:54:00 AM »
If you want cheaper 1.25" possils 10mm, 20mm, and 30mm may make a good set; assuming your "kid" scope does not accept 2" eyepieces.

Wide eyepieces make it easier to find objects if they are large enough to see. Higher powers 300x and higher are rarely used.

Philip Price

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Re: First Telescope - What eye piece to get/avoid?
« Reply #4 on: January 04, 2018, 04:27:28 PM »
Quote
Quote

Hi,

 I bought a Celestron Powerseeker 80eq for my kids and want to get a decent eyepiece to view the moon and planets as best this scope can do...without breaking the bank. I know nothing of the subject beyond all the confusing reading I've done.

I'm also getting the Omni 40mm 1.25" Plossl. Is this a horrible decision or are the reviews reliable?

Lastly, I've been in IT for over 20 years and enjoy tinkering, but I want to get it going fairly quickly without overdoing my typical detail work and driving my 2 little girls crazy as they wait to use it after opening on Christmas morning. Are there any tips for things to avoid that people tend to waste time on as they set a first time scope?

I'm so excited to use the scope with my kids. I've already begun plans to build a viewing platform in our back yard and nobody knows why.

Thanks for any help or suggestions.

Well since you asked about avoiding wasting time, my advice is that this is not going to be a great first scope.

1. The 80mm aperture is limited compared to larger apertures you can get for less money
2. Equatorial mounts like these are quite flimsy, and very hard to aim the telescope with. They're *especially* cumbersome with long refractors.
3. This scope comes with a cheap, low-grade erecting prism diagonal so it can be used for terrestrial viewing, but this impedes its overall optical quality

For less money, you can buy a more capable, simpler to use telescope:

https://explorescien...ts/fl-n114500tn

1. 114mm aperture vs 80mm aperture will be better for the moon and planets. I own a 114mm telescope and it's also verycapable of seeing deep space stuff.
2. The alt-az mount is FAR simpler to use and aim the telescope with
3. It's $50 less than the PowerSeeker
4. The shorter focal ratio will allow for wider field, low power scanning of the Milky Way

I know that's probably outside the scope of your request, but if possible, I would return the PowerSeeker and buy that Explore Scientific.

An alternative would be the Meade Lightbridge Mini 114 table top dobsonian, or if you're willing to stretch your budget a bit, the Meade Lightbridge Mini 130.
He already bought the 80mm scope. But if he is wiling to return it and order a 114mm I would agree they will be able to find and see more.

Jim Parker

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Re: First Telescope - What eye piece to get/avoid?
« Reply #5 on: January 09, 2018, 10:06:18 PM »
Quote
Quote

Hi,

 I bought a Celestron Powerseeker 80eq for my kids and want to get a decent eyepiece to view the moon and planets as best this scope can do...without breaking the bank. I know nothing of the subject beyond all the confusing reading I've done.

I'm also getting the Omni 40mm 1.25" Plossl. Is this a horrible decision or are the reviews reliable?

Lastly, I've been in IT for over 20 years and enjoy tinkering, but I want to get it going fairly quickly without overdoing my typical detail work and driving my 2 little girls crazy as they wait to use it after opening on Christmas morning. Are there any tips for things to avoid that people tend to waste time on as they set a first time scope?

I'm so excited to use the scope with my kids. I've already begun plans to build a viewing platform in our back yard and nobody knows why.

Thanks for any help or suggestions.

Avoid a 40mm 1.25" possil (although I have one).

If you want a 40mm make it a 2" 68-70 AFOV for maximum TFOV.

If you want a 30mm make it a 2" 82 AFOV

Maximum TFOV for a 1.25" would be 24mm 68 AFOV panoptic or equivalent.
You want him to buy a $300 eyepiece for a $130 scope!!! That's ridiculous. His scope doesn't even have a 2" focuser!

Justin Prasad

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Re: First Telescope - What eye piece to get/avoid?
« Reply #6 on: January 11, 2018, 03:28:06 AM »
We have the start of a department telescope riot here. As the OP has guessed by now, there is a lot of frustration in our forum with these types of telescopes. Just one caution, an expensive eyepiece will not make much difference with this telescope. Spend that money on a better telescope, and you will be a lot happier.

nonbuysalcho

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Re: First Telescope - What eye piece to get/avoid?
« Reply #7 on: January 15, 2018, 10:38:21 AM »
Quote
Hi,

 I bought a Celestron Powerseeker 80eq for my kids and want to get a decent eyepiece to view the moon and planets as best this scope can do...without breaking the bank. I know nothing of the subject beyond all the confusing reading I've done.

I'm also getting the Omni 40mm 1.25" Plossl. Is this a horrible decision or are the reviews reliable?

Lastly, I've been in IT for over 20 years and enjoy tinkering, but I want to get it going fairly quickly without overdoing my typical detail work and driving my 2 little girls crazy as they wait to use it after opening on Christmas morning. Are there any tips for things to avoid that people tend to waste time on as they set a first time scope?

I'm so excited to use the scope with my kids. I've already begun plans to build a viewing platform in our back yard and nobody knows why.

Thanks for any help or suggestions.

I think for a scope of this type the 40mm Plossl is okay. A 32mm might be better as it will give the same true field and a slightly higher magnification/larger image scale. Just as easy to use to find things (FOV is the same) but the moon or whatever is bigger. Also bright objects like the Moon take magnification pretty well and reveal lots of detail with magnification in any telescope. On the other hand, as magnification goes up, FOV decreases making keeping the target centered more frustrating for young explorers. Likewise EQ mounts are less intuitive than alt-az mounts, especially for young beginners. I would look into converting the eq mount into an alt-az mount (usually doable by setting the polar altitude adjustment to 0 degrees, leveling the polar axis with the horizon/ground rather than trying to set it to offset your latitude.

For a higher power eyepiece I wouldn't go above 100x, so a 10mm should be pretty decent at balancing FOV with image scale. Incidentally this scope normally comes with two eyepieces and a Barlow. The 4mm is too much, Barlowed or not, for the somewhat spindly mount. Here's something else to consider; if you get the 3x Barlow that comes with the kit and use it with a 32mm Plossl, you probably don't need any other eyepiece. Just Barlow the 32mm Plossl for a ~10mm focal length.

Best,

Jim

renjaysunsdis

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Re: First Telescope - What eye piece to get/avoid?
« Reply #8 on: January 15, 2018, 01:49:57 PM »
+1 vote to return it if possible
My first scope was a EQ powerseeker nearly 10 years ago and I also think it's likely to be frustrating finding objects in the sky given the unintuitive eq axes of motion. Not much seems to have changed in the specs, that 4mm and barlow will be worthless. I'd say get the 40mm and that's it, play with the scope a little to see if this is something you want to keep or see yourself spending time with before you spend more money.

Tommy Farley

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Re: First Telescope - What eye piece to get/avoid?
« Reply #9 on: January 18, 2018, 09:13:50 AM »
An 80mm F/11 equatorial mounted telescope is a decent choice for a first telescope. It will provide great views of the moon and allow you to recognize Jupiter and Saturn as planets.An equatorial mount isn't the easiest to learn to use, but it is not that hard, and properly set up, it allows you to counteract the earths rotation with just moving the scope on one axis. You can also very affordably upgrade to include a motor to provide tracking.

My main reservation for the scope you have selected would be the stability of the mount and tripod. At F/11 you have a long tube, and a shaky mount will be problematic. There are a number of steps you could take to improve the tripod, though (lots of ideas here on CN).

At F/11, the 40mm plossl is a good choice. It gives you the widest true field you can fit into a 1.25" barrel (even if the apparent field is narrow), and the low level of magnification means a brighter view for extended objects. The 32mm will give a slightly higher-power (but then slightly dimmer) version of the same field. There arguments for both.  At F/11, I don't think there is a wrong answer.

Of the eyepieces provided with the telescope, the 20mm is probably usable, the 4mm is useless, and the 3X barlow is likely junk. I'd also be concerned about the quality of the diagonal.

Bargain beginner telescopes are often frustrating for their users. Shaky mounts and poor quality accessories do not make for a joyful experience. Many people will recommend some sort of mini-dobsonian reflector. And yes, it is a good choice. However the long-focus equatorial refractor is not without its merits, too: no need for collimation, good performance with inexpensive eyepieces, the ability to to have automated tracking, the fact it can be used terrestrially, and the fact that it looks like a telescope.

John Jankowski

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Re: First Telescope - What eye piece to get/avoid?
« Reply #10 on: January 20, 2018, 03:20:49 PM »
Btw I think the GSO 32mm plossl (Celestron Omni plossl is mostly likely a rebrand with markup) is a better choice than the 40mm. Also maybe ask to move this thread to the beginners section, you'll receive more responses there.

pafunsirep

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Re: First Telescope - What eye piece to get/avoid?
« Reply #11 on: January 21, 2018, 10:54:06 AM »
I agree with the return if possible... I have not seen this particular scope, but if it is like the department store scope of my early days, my experiences with it at 12 yrs old caused me to give up on the hobby until I was about 50... results may vary!

elunmolunch

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Re: First Telescope - What eye piece to get/avoid?
« Reply #12 on: January 30, 2018, 03:02:27 PM »
You don't mention the ages of your children. If they are 3 and 5 years old, do not expect them to enjoy any view other than the Moon. If your kids are 9 and 11 years old, they might get bored with a scope of this size. Please consider the previous posters' advice about alternate instruments.

An option is a zoom eyepiece. If you can find one that tops out at 24mm focal length, that would be ideal. You can find them, and other eyepieces, used on the Cloudy Nights classified ads. Stressing about the quality of an eyepiece with a telescope of this size is a waste of your valuable time.

As an IT person, I am sure you have investigated all kinds of software and apps. May I suggest a simple cardboard or plastic planisphere (star wheel). You and your kids can easily understand how the sky moves by rotating the view. Also, you can see the entire sky in the view of a planisphere. Just about all apps and software only let you see a fraction of the sky at a time.

The tripod is metal, and does not dampen out vibration well. If you are handy, build yourself a wood tripod. It does not have to be fancy. There are DIY instructions on the Cloudy Night website for doing this. After spending a few evenings frustrated with the mounting system for this scope, you might also want to build a better mount for it. A mount is not the same as a tripod.

You don't mention where you live. If it is chilly outside in December, your kids, and you, might get cold. When using a telescope, you are outside standing still. Unlike cross country skiing, you won't be generating much body heat standing around.

I think an 18mm eyepiece is as small in focal length as you should go.

Best of luck, and I hope your family enjoys the scope!

Greg Fleming

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Re: First Telescope - What eye piece to get/avoid?
« Reply #13 on: January 30, 2018, 03:21:57 PM »
Quote
Hi,

 I bought a Celestron Powerseeker 80eq for my kids and want to get a decent eyepiece to view the moon and planets as best this scope can do...without breaking the bank. I know nothing of the subject beyond all the confusing reading I've done.

I'm also getting the Omni 40mm 1.25" Plossl. Is this a horrible decision or are the reviews reliable?

Lastly, I've been in IT for over 20 years and enjoy tinkering, but I want to get it going fairly quickly without overdoing my typical detail work and driving my 2 little girls crazy as they wait to use it after opening on Christmas morning. Are there any tips for things to avoid that people tend to waste time on as they set a first time scope?

Yes. Don't let one of those things you waste time on become worrying about if you've made a bad purchase, or what else you may need to buy on the advice of others and diminish the obvious enthusiasm you have as you embark on this wonderful hobby. You'll be doing fine with what you have and you've already made the great choice of bringing your children along for the journey. Don't get me wrong, there's good advice here, but at the end of the day its all subject to the personal preferences and idiosyncrasies of the one doing the opining. I'd highly recommend that you first use your telescope, get to know it, learn it's good and bad habits for yourself before you do anything else. Form your own opinions with what you learn and temper those with the knowledge you gain here and you will be well guided. Its along journey, don't allow your first step to be polluted with regret. Have fun, because you've only just begun.

David Lipson

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Re: First Telescope - What eye piece to get/avoid?
« Reply #14 on: January 31, 2018, 07:07:35 AM »
OK, 80mm guess refractor and (found it) 900mm focal length.
So you have a 40mm plossl, put it in and use it, I have one somewhere and likely a worse one then yours. Mine was really, really cheap.But I bought it for a slightly different reason.

The problem you may experience is the eye relief, at 40mm it should be up around 26mm so you could find you, or kids, are having to hold their head/eye some distance from the actual eyepiece. They will think it funny, you will not.

A 32mm may have been better as the field of view ould have come out the same and you would have abit more magnification and a bit less eye relief. Sort of easier.

Don't worry, it is called a learning curve. We have all been there and all done it. I bought a set of 6 plossls, not great ones but better then most scopes now come with. I gave them away to someone who was starting out. They were really happy at my "mistake".

Scope if f/11 so most reasonable plossls will work. However at the shorter end the eye relief is short. So you go from too much to too little.

I suggest nothing really less then an 8mm plossl and that may be unusable, about 6mm eye relief. If you wear glasses then 8mm is likely to be too short.

Would do my normal and say look at the Paradigms but 3 of those cost more then the scope, so a bit hesitant. 4 plossls at say 32mm, 20mm, 12mm and maybe 8mm. Although you will read the scope is capable of 160x I suggest you are cautious of this, 120 may be the real limit. And 900/120 = 7.5mm eyepiece.

Enjoy the scope it should be good fun, I have a small 70mm and it is the most used. Moon should be good in yours, Jupiter also at around 80x (10mm or 12mm EP).For Saturn you will need the 8mm or a bit less. Search out double stars and certainly try Albireo and Almaak.