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Beginner's telescope - advice needed


Oafman

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So, my brother has decided to buy his first telescope. As we both know next to nothing on this subject I figured it was worth asking for tips here, as I'm sure we have many knowledgeable members.

He has a budget of around £400 (US$600). He doesn't have any particular objectives, in terms of what he wants to look at, just cool things in space. Well actually I know the first thing he wants to see is Jupiter and the Galilean moons.

It will be used in suburban London, where cloud cover is bad and light pollution even worse, so we're not expecting miracles, but still hope to be able to get a good look at a few reasonably bright things.

He's not sure if he'll want to take photos, though I suspect he probably will in time. So that's not an immediate priority but it would be nice to have a telescope which will subsequently be suitable for that.

So does anyone have experience, thoughts or tips on the sort of telescope he should get?

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I'm a big fan of the Astronomers Without Borders 'OneSky' telescope. Good telescope, $200 (I don't know what it goes for in the UK), sold at cost, and it's for a good cause.

http://store.astronomerswithoutborders.org/index.php?main_page=product_info&cPath=5&products_id=4&zenid=qq9lp4uc8dl621rlpt2i5gua14

Use the extra money to buy a nice mount (or whatever it's called, I have no idea).

There is some good discussion and some delightful photography which illustrates the telescope's capabilities in this thread. Have a peek:

http://www.cloudynights.com/topic/463109-onesky-newtonian-astronomers-without-borders/

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I'd say forget about photography, especially at that budget. On amateur astronomy forums, we see something like this A LOT:

"Hey I'm a beginner, I want a good telescope to look at things with, and I'd like it to have the ability to take photos later if I want it to."

I'd say, again, tell your brother to forget about the photography/imaging, unless he's really serious about doing it. A lot of beginners handicap themselves by trying to get a telescope that can also do photography, and spend way too much on an unwieldy, large mount, and then never get into imaging in the first place, and then wish they had just gotten a visual-only telescope. Good mounts are expensive, and $600 USD isn't going to get you very far. For that much, you should be able to get something that should allow you to take images of planets, but negatively subtract hugely from the quality of telescope that you get. You can probably forget about deep space object imaging.

Heck, these days sometimes you don't even need a mount, you can put a digital camera on the ground and take a bunch of like 15 second exposures (short enough to avoid star trails) and then stack a whole bunch of them to make some nice Milky Way vistas... but you won't be doing that in the UK outside of Scotland, probably.

Anyway, yea, for that price he should just go for some good optics on a stable mount that is easy to use. Dobsonians are the best value for the money, but their relative value goes down somewhat if you live in a place that is too heavily light polluted to see the stars very well (the UK is one of the worst places in the world to do astronomy, sorry to say).

Anyway, I'd recommend either a 150- 250 mm Dobsonian (if your brother wants to look at some of the tens of thousands of deep sky objects like galaxies, star clusters and nebulae that can be seen with such a telescope) or good quality refractor on a solid alt-az mount (or maybe whatever the equivalent is of a CG-5 these days). The refractor is a rather small telescope, but in the hands of a beginner, it is still a magical instrument. The Dobsonian will absolutely blow it away on deep sky objects, and if the mirror's figure is halfway decent, it will also beat the refractor on planetary views, but again, if the light pollution is bad enough, there will be very little in the way of deep sky objects to look at.

Edited by |Velocity|
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I have been looking for a telescope in a similar price range for the past 3 months. I purchased a pair of binoculars around the time I started looking, and have been quite pleased with them, and most amateur astronomy things that I have read recommend binos and a book to get started in astronomy. I have been able to see Jupiter and a 2-3 of its moons, though not in any detail, just as points of light. I also got a night sky map app (sky guide) that has been great for finding objects to see with my binos. On the telescope front, I have pretty much settled on an 8 inch (approx. 200mm) Dobsonian, with decent ones starting at around 350 USD, (approx 240 pounds), but have yet to decide on the manufacturer of the scope (Zhumell, Orion, Atro-Tech, Skywatcher and more).

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Thanks, that's very helpful.

I'm sure that deep sky objects won't be possible, the sky here glows from the lights of London. So perhaps a refractor will be best.

Any suggestions of makes and models would be welcome, especially those which are particularly easy to use. I'll pass on the info so far and see if he has further questions.

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Lots of good advice above, I am going to point out some general principals to consider:

1) Aperture size is the #1 most important stat. Many newbies think it is magnification sometimes called power. This is false. The issue is that things are FAINT and hard to see not SMALL and hard to see. A 150 power magnification is way more than enough to see anything you want to see with a telescope in light polluted areas. Even if you do decide to go for magnification, aperture is still the most important feature as a larger aperture allows a larger useful magnification. Many cheap telescopes have a small 60 mm aperture and 500 magnification. That means they have the optics that mathematically works out to 500+ power so they are allowed to claim it, but they don't have the aperture to support it and you will not be able to really see anything at that power. In addition they use a cheap Barlow to boost the power. A Barlow is an adapter that increases the power by a factor of 2 or 3. So a 3x Barlow turns a 150 power telescope into a 450. The problem with that is a cheap one will also boost the flaws in the mirrors or eyepieces and ruin your picture. The takeaway from all this: Ignore magnification/power, go for aperture. #1 most important stat. By far.

2)Aperture is king. Yes this is a repeat.

3)The kinds of telescopes available to you vary. The two big ones are reflectors and refractors. Reflectors give the most aperture for you money but also more maintenance. I still recommend reflectors though, Dkmdlb above recommended a reflector.

4) I paid $550 Canadian Dollars for my reflector, it was a 5 1/4 inch (135 mm) reflector, it has a computerized mount that after a simple lineup procedure, will point to things like Mars, Andromeda, Orion Nebula. Just to give you an idea of what you can get for your budget.

5) Consider getting a cheaper one like what Dkmdlb suggested and then also getting an eyepiece set. A set of eyepieces from the same manufacturer can often be changed without wrecking your focus. Also keep a lookout for eyepiece filters, they often come in eyepiece sets and often include a light pollution filter. A light pollution filter is not magic, but it helps a great deal.

6) Telescope cameras are readily available that fit into standard telescope eyepices slots without adapters. The only concern I have with that is, looking at dkmdlb's recommended scope, I see it is a kind of reflector called a light bridge, are those rods durable enough to hold a camera in the eyepiece? Probably they are, but this is just a heads up on the sort of things to be considered.

7) Check your local area for a astronomy club. They can give you specific advice for your local area as well as give you an opportunity to try out different telescope styles before you buy one.

Edited by Leszek
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The nice thing about a very portable scope for urban areas is that you can always go out of town, and actually take it with you without much trouble. Not a huge problem here in the desert SW of the US, but even well above town (+500m), with decent seeing given the light pollution below, if I get in the car and drive 30 minutes, I can almost read by starlight. The first small scope linked is nice, as it is very inexpensive, and portable (albeit small aperture). You could get a big dobsonian, but then you have to lug it around for dark skies. I might be inclined to suggest a small scope, and a nice pair of binos.

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Reflectors give the most aperture for you money but also more maintenance. I still recommend reflectors though, Dkmdlb above recommended a reflector.

What sort of maintenance? My brother is reasonably technically minded, but won't have the time or knowledge to do anything too complicated. Ease of use will definitely be a factor in his decision.

The scope that Dkmdlb suggested, from Astronomers Without Borders, seems to only be available from them in North America (what happened to the absence of borders!). But I'll tell him to see if it is available here through other routes.

4) I paid $550 Canadian Dollars for my reflector, it was a 5 1/4 inch (135 mm) reflector, it has a computerized mount that after a simple lineup procedure, will point to things like Mars, Andromeda, Orion Nebula. Just to give you an idea of what you can get for your budget.

He does want a mount that will automatically point to objects, as he doesn't expect to have the time to start consulting charts and manually finding things. It sounds like this will be achievable within his budget

A light pollution filter is not magic, but it helps a great deal.

I didn't know of such things, but yeah, he'll need all the help he can get in that regard.

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I recently bought a pair of these large binoculars:http://www.amazon.com/Celestron-71018-SkyMaster-20x80-Binoculars/dp/B0007UQNTU

They easily show the 4 Galilean moons of Jupiter as well as many deep sky objects. I was amazed how well I could see the Orion Nebula! You will need a tripod, but I highly recommend these. If he does get a scope, these would make great company to it.

Edited by Dartguy
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I recently bought a pair of these large binoculars:http://www.amazon.com/Celestron-71018-SkyMaster-20x80-Binoculars/dp/B0007UQNTU

They easily show the 4 Galilean moons of Jupiter as well as many distant sky objects. I was amazed how well I could see the Orion Nebula! You will need a tripod, but I highly recommend these. If he does get a scope, these would make great company to it.

I don't understand why he would want both. Wouldn't the telescope always be better?

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I don't understand why he would want both. Wouldn't the telescope always be better?

I also have a telescope. But the binoculars are great for wide angle viewing and spotting for the scope. They are also great for daytime viewing, unlike the scope. BTW, the scope is a RV-6 from the 1960's, still a great scope.

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What sort of maintenance? My brother is reasonably technically minded, but won't have the time or knowledge to do anything too complicated. Ease of use will definitely be a factor in his decision.

The scope that Dkmdlb suggested, from Astronomers Without Borders, seems to only be available from them in North America (what happened to the absence of borders!). But I'll tell him to see if it is available here through other routes.

Reflectors require collimation. The reflector typically has two mirrors. One at the bottom and one tilted 45 degrees to aim for the eyepiece. These mirrors have to aligned. Most scopes do this with the help of screws. My telescope (and most similar sized reflectors) has 6 screws for the main mirror, 3 to lock it in place and 3 to adjust its angle. The 45 degree mirror had a simpler arrangement but I can't remember without looking. The basic procedure is to look through the empty eyepiece socket and adjust the main mirror until everything is centered. The 45 degree mirror then gets adjusted forwards and back to make sure it is in the center. The angle itself isn't adjustable, we just move the mirror so that it is in the center. Transport of the telescope out to a field to look around may jostle the mirror. Smaller scopes like the sort you are looking at would typically need to have this done once or twice a season, larger scopes might need to do this every time they setup. The scope normally comes with instructions on how to do this, but if not the internet has many tutorials on the subject. Some scopes come with a collimation eyepiece, which basically is just a smaller hole to look through to make things easier. I use a laser collimator for my scope, it fits in the eyepiece and when the laser comes right back straight you are setup. This sort of thing is overkill for most scopes of the level you are looking at.

He does want a mount that will automatically point to objects, as he doesn't expect to have the time to start consulting charts and manually finding things. It sounds like this will be achievable within his budget

It should be doable, mounts can be purchased separatly. Look at websites like telescopes.com for general idea of what is available. The local stores can usually order them for you and save on shipping and it is easier if you know what you are looking for.

Having said that, it isn't that hard to manually aim and point your scope. Most planets are easy to see and the learning curve overall wasn't nearly as hard as the first time I tried to get to orbit in KSP. If your scope doesn't come with one, I would recommend giving it a try. Many days when I setup I don't bother lining up my scope anymore.

Finally a computerized mount can do things like track the stars for you. They are moving across the sky faster then you think, within about 45 seconds they are normally out of view, a tracking scope can help that a lot.

Over all I would say if your scope doesn't come with one, try without first. It isn't that hard.

I didn't know of such things, but yeah, he'll need all the help he can get in that regard.

I would talk to a local club before I went out of my way for that stuff. Light pollution filters work by filtering out the light at around the colour of incandescent streetlights. Nowadays many cities are going to fluorescent or LED streetlights and those are a different colour. A local club would know how well they work in your area.

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My own suggestion is to get a scope that have f/D of around 6 to 10. Below that are fast scopes, which are great to see deep sky objects/DSOs (nebulas, galaxies, clusters), while higher than that are good for planets and solar system bodies. Low f/D is also good for scanning (say, find a comet or such). Mind that for galaxies and nebulas not the magnitude that makes you able/not able to see it, it's the surface brightness.

If your brother wants to make the scope points for him, get a computerized mounting. The scope could be anything. My own suggestion is to actually encourage him to learn manual pointing and focusing - while could be a bit hard, he'll enjoy what he see more than if the mount points it out for him.

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