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Amature Astronomer, need help with a Telescope.


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Hi

I was recently given a telescope set by someone, I assembled it and took it out to have a look at the clear night sky. After some practice I was able to point it at the moon and have some good view but that is about it, I seem unable to see any the planets, either never find them even if I am point righting at them or they are very dim with no detail at all. I have 3 lenses, a 20mm, 12.5mm and a 5mm, none seem to come up with any better results as I tried. I wondering if there would be any advise for a novice like me here.

Problems:

1) The reason I can't see anything smaller then the moon is that I am just not good yet are handling the telescope and should get more practice.

2) The reason I can't see anything is because the telescope is just too goddam cheap and not really good at looking at the star. (I believe this is a store bought set from the post office.)

3) A combination of reasons 1 and 2.

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Probably a mix. You should at least be able to see Jupiter and its moons and maybe get Venus' phase in even the crappiest store-bought telescope. I know becasue I had one when I was in high school. I could also *just* tell that Saturn had little bumps on its side (It happened at the time to be perfectly tilted. I think it's heading toward that that now as well?)

Does the telescope have a finder scope? The first thing you need to do is align that (use the Moon, or any far away target during the day like a distant water tower). Then, get something (I like Google Sky for Android phones) that will tell you where the planet you want to see is. Center the planet in the finder scope and then look through the main scope. Do a few sweeping passes and your target will fly through the center eventually. Be patient, moving the scope in tiny increments around until bam. There it is. Then focus.

It's an art more than a science getting these things working, and the payoff can be little. But it's still worth it IMO especially if you've never laid (your own, actual) eyes on Jupiter before.

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Have you removed the objective lens cap? :P

I bet you're just not being able to align the telescope well enough. Your lens are ocular pieces. Tell us the focal length (roughly the tube length) and the objective lens diameter so we can calculate the magnification.

Always start with the largest lense because high magnifications yield low field of view, therefore slight nudge and there goes your planet. It's annoyingly difficult to point store bought telescopes to the target.

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Jupiter is a good bet right now. At 21:00 local, it's about straight up here at 35 degrees latitude, and the brightest thing in that position. You can make out 4 moons even with good binoculars (4 are not always visible at any given time). Check out the moon ideally when no where near full, so there are better shadows to show detail.

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Jupiter is a good bet right now. At 21:00 local, it's about straight up here at 35 degrees latitude, and the brightest thing in that position. You can make out 4 moons even with good binoculars (4 are not always visible at any given time). Check out the moon ideally when no where near full, so there are better shadows to show detail.

I can confirm, even with moderate light pollution I was able to make out 2 of Jupiters moons with a pair of binoculars, even with the Moon being half full. I would recommend getting the Sky Guide app and a good pair of binocs for intro to stargazing. However I can't say anything about a telescope.

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Refractors are fun, though obviously you want a larger objective for deep sky stuff… and dark skies. The Great Nebula in Orion is also easy to spot with any scope as it is a naked eye object (least out here in the high desert). Venus is easy to spot as well, but not terribly satisfying. Mars can look nice in a small telescope as well---oh, and of course Saturn.

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As mentioned above you should align the finder sight first, best to do during the day. Use the 5mm eyepiece and a distant object to do it.

The smaller the eyepiece you use the harder it is to get a good view at night. So after you point it at something like Jupiter you should start with your 20mm eyepiece first. With that eyepiece you have a 35x magnification which is more than enough to see good stuff. Depending on the light pollution in the area the 20mm eyepiece is best for looking at something like Andromeda. (Which will fill the whole view easily. I didn't realize until I saw it with my own telescope, it takes up more space in the sky than the full moon.) After you can find and focus something like Jupiter with the 20mm eyepiece, only then should you go to the smaller eyepieces. Since your eyepieces came with the telescope (I assume) you shouldn't need to refocus after changing eyepieces. (In general this is true for eyepieces that come in a set, or eyepieces of the same type by the same manufacturer.)

The smaller the eyepiece the higher the magnification (Focal length/eyepiece) but the more difficult it is to focus. The aperture is the important stat. The bigger it is, the more light you collect, the easier to see faint stuff and the easier it is to focus. The 5mm eyepiece gives you 140x magnification but with a 60mm aperture the best you can do with it is viewing things on the ground during the day and very bright things like the moon at night. That isn't to say don't try to view Jupiter with it, sometimes it is bright enough, just don't expect crystal clear pictures.

If you live in the city, check to see if your telescope came with some eyepiece filters. One of them is usually for filtering out light pollution. It isn't magic, but it does improve things a bit.

More expensive telescopes can give you a better view but also come with other things you need to learn like cullimating the telescope. Just out of curiosity, what is the brand name of the scope you have?

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Guys, i'm thinking about purchasing something better than my beat-up binocular. I found a Celestron C70 Mini MAK 25x75x70. It's a Maksutov-Cassegrain system, with 70 mm aperture. Focal lenght is 750 mm. What do you think about this one? It's dirt cheap, but weather in my place is abysmal for amateur sky watchers. Usually only a couple of clear nights per month - so i don't really want to invest into something more capable, because i will get very little mileage out of it.

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Some advice: If you got very bad observing conditions, you might want to use telescopes with small focus/diameter (often said as f-ratio, f/D or f stop for those in photography), try to get one below (or equal to) 10. Other than you can observe a wider area at once (compared to others with the same diameter), lower f/D means simply more light, for the same diameter. Would also helps you if you choose to take astrophotography - lower f/D means faster exposure times. Mind that the later needs motor at the mounting for very best results ! You don't need it if you're taking it at fraction of seconds.

Binoculars mostly have lower f/D compared to telescopes.

EDIT : If all else fails (or you want to utilize what's there), try to use lower-power eyepieces first (that is, those which yields lower magnification - so longer focus). Familiarize yourself with the movement of the telescope, and the movement of objects seen from the telescope. Using your 20 mm eyepiece with 700 mm telescope, Jupiter might still be only a little more than a dot - so just refer to the "real" sky, those directly visible to your eyes. With time and patience, you should adapt better - your pointing should improve, and your eye limiting magnitude might increase a bit (hence why at last I prefer naked eye over telescopes for daily watching).

Edited by YNM
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I just rechecked the specs. My telescope is a 60mm aperture with a 700 mm focal length. The type of telescope is a refractor.

As magnification is focal length divided by ocular lens diameter, and your focal length is 700 mm, your available magnifications are:

a) for 20 mm ocular lens: 35x

B) for 12.5 mm: 56x

c) for 5 mm: 140x

Those are perfectly enough powerful magnifications for observing Venus phases, Saturn's rings, Galilean satellites, Martian polar cap(s) if the conditions are great but barely.

60 mm objective lens is enough to collect enough light to see Uranus as a bluish dot. Ceres sometimes, not now as it's too dim.

Deep space objects you can look for are Orion's nebula, Pleiades (lowest magnification), etc.

You can also use it to project the Sun on a piece of paper. Never look at the Sun through the eyepiece.

You're just not pointing it correctly. Always start with the lowest magnification and go up.

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You can also use it to project the Sun on a piece of paper. Never look at the Sun through the eyepiece.

With a 60mm aperture this might be fine, but be careful, it is possible to damage the telescope this way so don't try it with someone else s scope. Especially if it has a bigger aperture than yours. Don't try this with children in the same room. Be wary, accidentally looking through the eyepiece when pointing at the sun will cause instant and permanent eye damage.

There are filters for this sort of thing that go over the front of the scope. This protects the scope and those using it. I would recommend you do not do this without one. Even with a sheet to project on the risk is just to great.

If you check google images you will see what I mean:

https://www.google.ca/search?q=telescope+sun+filter&source=lnms&tbm=isch&sa=X&ei=hvkaVcbUNMSYyASHyYC4CQ&ved=0CAcQ_AUoAQ&biw=1920&bih=969

Also in the same set of search results is a melted eyepiece, what if that had been somebodies eye?

Edited by Leszek
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You can't damage a refractor telescope by doing a Sun projection. Reflector yes (barely), but not refractors.

Direct looking into the Sun using a telescope is possible, but one needs a specialized solar filter (usually Baader one) and it always goes on the objective lens. There are no alternatives. None.

And if anyone has any ocular lens filters, do not use it.

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You can't damage a refractor telescope by doing a Sun projection. Reflector yes (barely), but not refractors.

Direct looking into the Sun using a telescope is possible, but one needs a specialized solar filter (usually Baader one) and it always goes on the objective lens. There are no alternatives. None.

And if anyone has any ocular lens filters, do not use it.

Ever heard of a Herschel Wedge?

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Ah. Well, true, that is correct. But to my defense, if you have a Herschel wedge, you don't fiddle with store bought kid telescopes. :)

Also, that thing alone is not enough for bringing the light intensity down to a safe level; additional filters are needed.

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Guys, i'm thinking about purchasing something better than my beat-up binocular. I found a Celestron C70 Mini MAK 25x75x70. It's a Maksutov-Cassegrain system, with 70 mm aperture. Focal lenght is 750 mm. What do you think about this one? It's dirt cheap, but weather in my place is abysmal for amateur sky watchers. Usually only a couple of clear nights per month - so i don't really want to invest into something more capable, because i will get very little mileage out of it.

I'd be a bit wary of it. I bought a 90mm Celestron Mak, one of the older ones with a lever that allows it to be used both as a spotting scope and as an astronomical telescope (flipping the lever one way allows the light to pass through a prism that makes things right-side-up, flipping it the other diverts the light 90 degrees up into a different eyepiece, meaning more light gets through for astronomical observing) , and well....it kind of sucks as an astronomical telescope, mostly because of build quality. There are shavings of some kind in the section leading to the "astronomy" eyepiece that can be seen while using it, kind of like "floaters" in your eye, and since that section is sealed up I can't get the shavings out.

If you can, go over it thoroughly to make sure there aren't any major issues.

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How much are you willing to spend, Scotius? How much room do you have to store the telescope? Not all cheap telescopes are small, depending on how you define "cheap". What do you want to use the telescope to look at? Do you want it to cross-over as a terrestrial spotting scope?

Personally, I've never particularly thought well of Maks (especially very small ones), but I'm a deep sky observer. They are good scopes but... refractors are simpler and offer similar image quality, and Newtonians are also simpler and offer much more aperture. Maks are compact though.

- - - Updated - - -

Hi

I was recently given a telescope set by someone, I assembled it and took it out to have a look at the clear night sky. After some practice I was able to point it at the moon and have some good view but that is about it, I seem unable to see any the planets, either never find them even if I am point righting at them or they are very dim with no detail at all. I have 3 lenses, a 20mm, 12.5mm and a 5mm, none seem to come up with any better results as I tried. I wondering if there would be any advise for a novice like me here.

Problems:

1) The reason I can't see anything smaller then the moon is that I am just not good yet are handling the telescope and should get more practice.

2) The reason I can't see anything is because the telescope is just too goddam cheap and not really good at looking at the star. (I believe this is a store bought set from the post office.)

3) A combination of reasons 1 and 2.

It's probably both 1 and 2. Sometimes though, you can supposedly transform a cheap telescope from an unusable piece of junk into a usable piece of junk just by getting better eyepieces. What size is the eyepiece barrel? There are generally two sizes that cheap telescopes come in for eyepieces- 0.965" (24.5 mm) or 1.25" (32 mm). If the scope uses 0.965" eyepieces, it's really junky, and the eyepieces that the telescope came with are likely to be plastic pieces of garbage. However, if you upgrade them to 0.965" eyepieces with actual glass lenses with antireflection coatings, it supposedly can help out a lot. If the telescope uses 1.25" eyepieces, you're in better luck, because the telescope itself is more likely to be of usable quality, and there is a vast array of quality 1.25" eyepieces to chose from. (2"and 1.25" eyepieces are used in quality telescope- generally, a quality telescope will accept 2" eyepieces and come with an adapter that allows it use 1.25" eyepieces too.)

Also, look at the front objective of your telescope. Do reflections in the objective lens look colored (like blue or green) or are they just normal-color? If there is no coloration, it means the lens is not coated with any kind of anti-reflection coatings, and it's of an extremely low quality- it could even be a plastic lens!

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Hey, don't sell the Moon short just because you can see it without a telescope. There's tons and tons of details there beyond "yawn, more craters."

Saturn is also starting to rise earlier in the night, if you can stay up to 10pm or so it should be the brightest object in the eastern sky, rising higher every night. Midnight would offer the best viewing.

The biggest problem with low end telescopes IME is the mount - If it is a standard tripod with the bar in the middle, try to add a little weight to the bar to stiffen the tripod so it doesn't shake so bad.

Easiest way to get the finder centered and figure out focus is to use Polaris, if it is visible from your location. It essentially doesn't move in the sky, so you don't need to worry about having to repoint the scope while trying to get everything aligned.

One way to help location planets is to wait for the Moon to get close to one so you can just hop from there. http://www.heavens-above.com/skychart.aspx has a free sky chart, you can see on the 7th/8th the Moon will be close to Saturn.

Aperture envy is a big problem. Remember that the little telescope you'll take out every weekend can have more entertainment value than the 20" monster that only leaves the garage once a season. If you're not likely to go to dark sky sites, a 6" or 8" telescope is more than enough for anything visible inside a city, and at a dark sky site capable of some very good views.

And H-A scopes are awesome! No need to wait for night. :)http://hendric.smugmug.com/Hobbies/Astronomy/Solar-Photos/i-Ld2kt4k

Edited by moronwrocket
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Aperture envy is a big problem. Remember that the little telescope you'll take out every weekend can have more entertainment value than the 20" monster that only leaves the garage once a season. If you're not likely to go to dark sky sites, a 6" or 8" telescope is more than enough for anything visible inside a city, and at a dark sky site capable of some very good views.

This is very true, and I'm the owner of a 25" scope. The best telescope is the one you'll use. I don't use my 25" scope much because the weather is so awful, and because I'm only willing to use it from dark skies, which require a 3.5 - 4 hour one-way drive to get to because there are almost zero public lands in dark areas of the state I currently reside in (it also takes about an hour each to both set the telescope up and tear it down, largely due to all the stupid dew heating crap I have to attach to it to keep it free of dew in this stupidly humid state). We do get some clear weekdays, but rarely do we get clear weekends during new moon. And a lot of the weekends that we get that are fairly clear are not clear enough for me to risk a 4 hour (again, one-way) drive. So there is also something like dark-sky envy- you can get spoiled by dark skies so badly that you are unwilling to even observe under suburban or mildly-polluted country skies. To me, if the site is not dark enough to see the Gegenschein, I'm not happy with observing under it. And truly, the difference between mildly light-polluted country skies and near pristine dark skies is no small difference, and I also tend to look at the kinds of low surface brightness objects that even small amounts of light pollution can ruin. Even higher surface brightness objects have low surface brightness regions that are ruined by even tiny amounts of light pollution. I always feel like I have to go after something new or I'm wasting my time, so I've "advanced" in the hobby so much that I have a hard time even doing the hobby anymore. I wish I could cure that and return to the "newbie magic" I had as a kid... but of course, it was easy to always look at new, radically different objects when you're just starting out. Oh and yes, there are hundreds of thousands of galaxies within reach of a 25" telescope- maybe millions of galaxies- but after a certain faintness they all look the same. Regardless, these days, that's what I typically look at to get my allotment of "new objects" in to make the observing session feel like a success. (Of course, I still look at all the bright "eye-candy" objects, but again, if I just look at "eye-candy" the whole session, I feel like the session was a "failure".)

Anyway, though, for a beginner, your sentiment is very true. A beginner does not need a big telescope. A beginner should not seek a big telescope. I started with 10X25 binoculars when I was 9 years old, and moved on to a 60 mm spotting scope. A few years later, I moved on to my first real telescope, a 4.5" reflector. I had a GREAT time, and found lots of galaxies and nebulae (just some I can remember spotting with my 4.5" scope were M81/M82, M65/M66, M51/NGC 5195, M31, M33, M57, M42, M78, and of course numerous star clusters). So small telescopes can do quite a lot! For someone interested in deep sky observing, I've always recommended a 6" or 8" Dobsonian, but it really depends. You can have fun with nothing but a 60 mm spotting scope, as I did, though you'll quickly run out of objects to look at if your sky is not very dark. The most important thing is that the telescope is usable and that it is used.

Edited by |Velocity|
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You've pretty much summed up my own thoughts Velocity :) Weather at my place is terrible for amateur astronomers most of the year. Even if there is no rain, then usually sky is covered by partial or complete cloud layer. I feel happy if i manage to catch five clear nights in a month. It was mostly for that reason i kept using my old, trusty binoculars for many years. I've seen no point in investing into something gathering dust for most of the year. Unfortunately recently i noticed that one of prisms became chipped :( It still serves great at day, but stars and planets became blurry smudges. Apparently its time to buy something new. That Celestron is small and light enough to be set up quickly on almost any surface, can be used at day to watch wildlife ( a perk of living close to a forest :) ) and with maximum magnification of 75x it should let me see some interesting details.

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Well, again, I'm not a big fan of Maks. Can you link the Celestron?

Personally though, if I were really going for a cheap, small Mak that can crossover for terrestrial use, I'd probably get something like this- http://www.telescope.com/Telescopes/Cassegrain-Telescopes/Orion-Apex-102mm-Maksutov-Cassegrain-Telescope/pc/-1/c/1/sc/14/p/9823.uts

Or the otherwise similar and slightly cheaper 90 mm version.

70 mm is quite small, and the quality of it might be a little suspect, even if it is Celestron.

Personally, I think a small apochromatic refractor might be a much better choice, such as maybe this-

http://www.telescope.com/Telescopes/Refractor-Telescopes/Refractor-Optical-Tube-Assemblies/Orion-ED80-80mm-f75-Apochromatic-Refractor-Telescope/pc/1/c/10/sc/346/p/9895.uts?refineByCategoryId=346

I have a 100mm achromatic refractor, and the chromatic aberration on the planets is annoying enough that I'd definitely recommend an apochromatic refractor if you can afford one. If I remember correctly, those Orion 80 mm apos got decent reviews when they first came out a few years back.

Anyway, remember than you get what you pay for. IMO, it's better to send a couple hundred dollars (or the Polish equivalent :)) and get a quality telescope you can use for the rest of your life than something cheap and flimsy that breaks and doesn't really do well what you want it to do.

Edited by |Velocity|
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