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Today, I got a telescope that my neighbor was giving away for $5.  It is a TwinStar AstroMark 80mm 16-40x Portable Refractor Telescope, which is normally valued at ~$40.  I set it up tonight and looked at Venus, but the image had lots of water spots on it.  I took the included lens wipe and wiped off the front lens, but the image did not improve very much.  The viewing aperture and a few of the other lenses looked kind of smudgy, but I did not want to try wiping them without knowing more about it.  Does anyone have any recommendations for cleaning the lenses of a telescope like this?  Also, could there be a focusing issue on my part?  I guess there could also be damage to the lenses, but I'm hoping that is not the case.  I was going to look at the moon to see how well it is resolved, but the moon is not going to be above the tree line where I live until after I go to bed.  If you have any recommendations for cheap, entry-level telescope accessories or even replacements in case this one is broken, please share.  This is my first telescope, so thank you for any help you can provide.

Edited by HeliosPh0enix
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Get lens cleaner and a lens cloth.  Spray and wipe all glass elements exposed to the air / dust. 

If after a thorough cleaning you are still getting issues, give it a gentle shake.  Listen for any loose elements inside.  If you suspect something may be loose inside, gently take the telescope apart and don't lose any pieces!  Fix anything that needs fixing, and try again. 

 

57 minutes ago, HeliosPh0enix said:

but the moon is not going to be above the tree line where I live until after I go to bed. 

Now I'm confused.   Either you go to bed REAL early, or you don't live on Earth.   It's a full moon tonight, which usually mean it comes up as the sun goes down.    Of course, I'm a night owl typing this at 0330 local time, so, I can't be one to judge.  :D

 

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4 minutes ago, Gargamel said:

Get lens cleaner and a lens cloth.  Spray and wipe all glass elements exposed to the air / dust. 

If after a thorough cleaning you are still getting issues, give it a gentle shake.  Listen for any loose elements inside.  If you suspect something may be loose inside, gently take the telescope apart and don't lose any pieces!  Fix anything that needs fixing, and try again. 

 

Now I'm confused.   Either you go to bed REAL early, or you don't live on Earth.   It's a full moon tonight, which usually mean it comes up as the sun goes down.    Of course, I'm a night owl typing this at 0330 local time, so, I can't be one to judge.  :D

 

I'm in Hawaii, so the timing might be a little different given the lower latitude.  There are some tall trees uphill to the side of my place in the direction that the moon is rising in, and it needs to be a good 30-40 degrees above the horizon for me to see it.  Judging by the track on my phone app, it won't be above that point until after 10 pm local time, and I have to get up early tomorrow, so no late night stargazing for me.

Edited by HeliosPh0enix
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Just now, HeliosPh0enix said:

There are some tall trees uphill to the side of my house in the direction that the moon is rising in, and it needs to be a good 30-40 degrees above the horizon for me to see it. 

Ahha!  Fair enough.  I forgot to consider topography when drafting my egocentric comment!

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2 hours ago, HeliosPh0enix said:

Today, I got a telescope that my neighbor was giving away for $5.  It is a TwinStar AstroMark 80mm 16-40x Portable Refractor Telescope, which is normally valued at ~$40.  I set it up tonight and looked at Venus, but the image had lots of water spots on it.  I took the included lens wipe and wiped off the front lens, but the image did not improve very much.  The viewing aperture and a few of the other lenses looked kind of smudgy, but I did not want to try wiping them without knowing more about it.  Does anyone have any recommendations for cleaning the lenses of a telescope like this?  Also, could there be a focusing issue on my part?  I guess there could also be damage to the lenses, but I'm hoping that is not the case.  I was going to look at the moon to see how well it is resolved, but the moon is not going to be above the tree line where I live until after I go to bed.  If you have any recommendations for cheap, entry-level telescope accessories or even replacements in case this one is broken, please share.  This is my first telescope, so thank you for any help you can provide.

Congrats on picking up a new great hobby! Unfortunately at that price point "a kind of smudgy" is pretty much what you can expect, but don't let that bring you down. Clean all the lenses like @Gargamel suggested and just go check out any targets of opportunity the sky offers you. I will return to you with some suggestions for small upgrades, unless other people beat me to it. You won't need to spend hundreds to get a clear view.

In three weeks you should have the moon perfectly placed for you. It is best viewed at half moon anyway when the lighting angle brings out all the details of the surface.

One obligatory safety warning though: stay away from those small sun filters that screw into the eyepiece. They have a tendency to crack and let full power of the sun into the eye destroying the sight. All solar observation must be done with a proper full size filter in front of the entire telescope. Or better yet a purpose built solar telescope.

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9 minutes ago, monophonic said:

In three weeks you should have the moon perfectly placed for you. It is best viewed at half moon anyway when the lighting angle brings out all the details of the surface.

Absolutely!  Some of my best images of the moon were taken at half moon.   The mountains and ridges stand out very distinctly on the horizon.    I'd also suspect that it is strong enough to take a look at Jupiter and Saturn, One of which is just a bit to the west of the Full moon tonight.  I'm guessing it's Jupiter from the brightness, but I haven't looked it up.  If Galileo could resolve the major moons of Jupiter, and the rings of Saturn, you should be able to also, I'd like to hope. 

12 minutes ago, monophonic said:

One obligatory safety warning though: stay away from those small sun filters that screw into the eyepiece. They have a tendency to crack and let full power of the sun into the eye destroying the sight. All solar observation must be done with a proper full size filter in front of the entire telescope. Or better yet a purpose built solar telescope.

Better yet, until you get some experience, or a Mentor with experience, just don't look at the sun. 

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Unfortunately what you've been given is pretty much a toy. Wouldn't bother wasting time/money making it work.

A list of recommended telescopes under $500:

Or alternatively you can get some astronomy binoculars for under $100:

 

Edited by _Augustus_
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Hi again @HeliosPh0enix!

What @_Augustus_ said, while rough, is unfortunately quite accurate. Do mind you don't have to upgrade for as long as you yourself are content with it - consider that @_Augustus_ has himself built at least two telescopes from scratch and fully ground the primary mirror for at least one of them! At his level his requirements are magnitudes beyond what I could even take any advantage of over a - several hundred $ - mass market telescope. Take your time, enjoy and don't listen to people who say you can't have fun without X-ton dollar equipment - I know I have ruined many a hobby for me by listening to them.

Only upgrade I would recommend for your telescope would be a cheap (and I do emphasize cheap, aim for the $10-$15 price range and "plossl" type) aftermarket eyepiece or two. Anything else will quickly dwarf the retail price of that scope. Still these mass produced eyepieces will be a magnitude better than what came with the scope and will max out the capability of it. They shouldn't be any worse than what comes with a lot more expensive telescopes either, as the manufacturers try to push down on the prices of most popular scopes and make a profit selling better eyepieces and accessories.

Another option is to get a good guide and a starmap or planisphere. There is a lot of beautiful sights to see in the sky, but a lot of it can be difficult to find, because there is really a lot of sky up there. These things can help with that. A book named "Turn left at Orion" is often recommended, but I haven't got it personally. A free software called Stellarium is also nice tool to have - but can be a handful to learn especially if you don't know the jargon yet.

 

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4 minutes ago, monophonic said:

Hi again @HeliosPh0enix!

What @_Augustus_ said, while rough, is unfortunately quite accurate. Do mind you don't have to upgrade for as long as you yourself are content with it - consider that @_Augustus_ has himself built at least two telescopes from scratch and fully ground the primary mirror for at least one of them! At his level his requirements are magnitudes beyond what I could even take any advantage of over a - several hundred $ - mass market telescope. Take your time, enjoy and don't listen to people who say you can't have fun without X-ton dollar equipment - I know I have ruined many a hobby for me by listening to them.

Only upgrade I would recommend for your telescope would be a cheap (and I do emphasize cheap, aim for the $10-$15 price range and "plossl" type) aftermarket eyepiece or two. Anything else will quickly dwarf the retail price of that scope. Still these mass produced eyepieces will be a magnitude better than what came with the scope and will max out the capability of it. They shouldn't be any worse than what comes with a lot more expensive telescopes either, as the manufacturers try to push down on the prices of most popular scopes and make a profit selling better eyepieces and accessories.

Another option is to get a good guide and a starmap or planisphere. There is a lot of beautiful sights to see in the sky, but a lot of it can be difficult to find, because there is really a lot of sky up there. These things can help with that. A book named "Turn left at Orion" is often recommended, but I haven't got it personally. A free software called Stellarium is also nice tool to have - but can be a handful to learn especially if you don't know the jargon yet.

 

My requirements actually aren't that high. One of my most-used telescopes is a 60mm refractor. However, OP's scope has poor optics and a poor mount, and it's quite possible it doesn't even take 1.25" eyepieces.

There are bare minimum requirements for a telescope to be usable, and OP's scope does not remotely reach them even with upgraded accessories.

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From the original description, i suspect the telescope doesn't have removable eyepieces like a "proper" astronomical scope; rather, it's a zoom model with internal erecting optics, intended for terrestrial targets.

As others have noted, the optics in a telescope of that type that sells new for $40 are likely to be pretty bad.  Fortunately, the Moon is a very forgiving object for observation.  You can make your own telescope and get pretty good views (Galileo did that, four hundred years ago, and learned enough to almost get burned at the stake).  In fact, if you know what you're doing, you could make a better telescope than what you have from the lenses in your telescope (first step would be to eliminate the zoom and erecting lenses, cut down to just the objective and eyepiece).

However, if you're not an experienced telescope builder, I'd keep the scope you have for watching the beaches (even 10x can get you views you'd never get if you were close) or birds (you've got some truly amazing birds in Hawaii), and try to save up $100 or so to get a scope that's designed for looking at the Moon and planets.  Do keep an eye on thrift stores; I've picked up a number of small Newtonian reflectors for next to nothing at Goodwill (though you won't find them there, now, everything really good goes on their auction site).  I've got one with a *two inch* primary mirror that can still give creditable views of the Moon, show the four biggest moons of Jupiter, give a hint that Saturn isn't just a ball in the sky (you can't really see the rings at low magnification, but you can get what Galileo did -- an idea that, perhaps, Saturn might have "ears"), and show the phases of Venus.  This instrument was originally sold as a toy in the 1970s, but the makers put real optics in it, and it does work.

If there's a Costco near you (I think there are a couple on the Big Island, and at one near Honolulu, but I could be wrong), watch them when they approach Christmas.  Every year I can remember, they've had some kind of telescope for sale in the $200 range, and they're usually quite acceptable instruments for the money.  Last time saw one (3-4 years ago) it was an 80 mm wide field refractor with diagonal and automatic mount (go through a setup process, and the controller can find any celestial object in its catalog in seconds), selling for $200.  It'd be a near-perfect instrument for Lunar observation, and should do a fine job with the planets, as well.

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15 hours ago, _Augustus_ said:

My requirements actually aren't that high. One of my most-used telescopes is a 60mm refractor. However, OP's scope has poor optics and a poor mount, and it's quite possible it doesn't even take 1.25" eyepieces.

There are bare minimum requirements for a telescope to be usable, and OP's scope does not remotely reach them even with upgraded accessories.

Yet your requirements are high enough to imply that an instrument than can verifiably produce a recognizable image of Venus is useless. Do me a favor and tell me how you felt, when starting that first mirror you did, about the posts that said your mirror grinding bench was useless? Also,

7 hours ago, Zeiss Ikon said:

From the original description, i suspect the telescope doesn't have removable eyepieces like a "proper" astronomical scope; rather, it's a zoom model with internal erecting optics, intended for terrestrial targets.

Dunno where you found the original description, but none of the Amazon listings for the scope I checked mention any erecting optics. Usually those would be mentioned in this price class under the "features" equal "value" marketing principle. They do however mention 10mm and 25mm 1,25" Kellner eyepieces. A cheap Kellner won't max out the image quality from a cheap 80mm achromatic doublet, however a cheap Plössl will and will also be adequate to start with in a better scope later on.

Please, guys, if you want to help grow this hobby, don't denigrate stuff that new people already bought. Especially don't denigrate it based on your own factually incorrect prejudices, when the real facts are just a quick google search away. For the fiver the OP paid that scope was a steal.

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1 hour ago, monophonic said:

Dunno where you found the original description, but none of the Amazon listings for the scope I checked mention any erecting optics.

I was going by the description in the OP for this thread; I must have missed the Amazon listings.  For that I apologize -- most of what I posted about making a better telescope by tossing parts of that one were based on believing it to be a different kind of telescope often sold with similar description.  I agree, a 25 mm Plossl would likely make that a very acceptable starter scope for the Moon (that'll give 16x, which is just about right for basic Lunar observation).  Get a 10 mm Plossl as well, and you'd be able to see anything in the usual realm of Solar System observations (when it's clean).

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  • 3 weeks later...
On 5/1/2018 at 10:38 AM, HeliosPh0enix said:

I'm in Hawaii, so the timing might be a little different given the lower latitude.  There are some tall trees uphill to the side of my place in the direction that the moon is rising in, and it needs to be a good 30-40 degrees above the horizon for me to see it.  Judging by the track on my phone app, it won't be above that point until after 10 pm local time, and I have to get up early tomorrow, so no late night stargazing for me.

Hi again @HeliosPh0enix,

Three weeks have gone by. The moon should now be very well placed for you in the early evening. It is also half moon, or the time of the month when the view will take your breath away, guaranteed. So if you haven't been out again with your telescope now is the time to go.

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