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So You Wanna Buy a Telescope: Advice for Beginners (2015)

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Re: So You Wanna Buy a Telescope: Advice for Beginners (2015)

#81

Post by aortega »

Avshalom wrote: post #65
aortega wrote: post #57

Earlier quoted context omitted.

Sure, if you are in the middle of the chilean desert.

That's not really how telescopes work. If it's light pollution additional aperture does not by itself preferentially distinguish between terrestrial and extra terrestrial light. If it's humidity, radiated heat and particulate matter you'll hit the diffraction limit of your local atmosphere before you hit the resolution of a half meter scope. N.B. if you have the money to buy a 1 meter scope and motorized mount suffic…

I have a big-ass telescope and it's the main reason I can see stuff in light pollution. The trick, that I'm sure you know, is to pickup a bucket-load of light, filter the pollution light and let pass the star light. They are different colors, basically.

Re: So You Wanna Buy a Telescope: Advice for Beginners (2015)

#82

Post by spdustin »

acqq wrote: post #48
_ph_ wrote: post #34

Earlier quoted context omitted.

Astrophotography without a telescope is indeed a good starting point. Get a bright 50mm lens and just with a simple barndoor tracker you can do amazing things. But as this article is about buying a telescope - and astrophotography through a telescope requires more skill than a complete beginner might imagine.

For those who don't know, this is what's possible without the telescope and the camera you can use for the other photos too: https://www.flickr.com/photos/119551085@N06/15418169222/in/a... Just Sony NEX-6, a tripod and 30 seconds on the (carefully selected) convenient place. Using image stacking software is also a fantastic tip, big thanks to the sibling comments.

Just that camera, stacking software, and the driest, darkest place on Earth (slight exaggeration) the Atacama Desert.

Excellent photo, though. I'd love to visit a site with such dark skies and good seeing.

Re: So You Wanna Buy a Telescope: Advice for Beginners (2015)

#83

Post by joshumax »

gus_massa wrote: post #67
mnw21cam wrote: post #38

Earlier quoted context omitted.

You don't even need a tracker at all. Just take a series of 20-second exposures, align them in hugin, and stack them. I have managed to get some remarkably good results this way, because the fact that the star background moves allows you to cancel out a lot of the noise that the camera and light pollution produces.

If the aligning phase can be automated, this looks like a nice plugin for ImageJ/ImageMagick or even an online version in a web page. (You an monetize it with ads about telescopes or something.) (Bonus points for a deconvolution filter. (Is it useful here?))

Two pieces of gratis software (DeepSkyStacker Live) and RegiStax already do something like this, as well as PixInsight and the venerable Maxim DL, among others.

Re: So You Wanna Buy a Telescope: Advice for Beginners (2015)

#84

Post by littleredstar »

Great summary article for beginners. Ed's been reviewing scopes for as long as I've been in the hobby. His advice is sound.

The best advice I can give beginners is to get out to a dark sky on a moonless clear night and enjoy the wonders above you. Maybe watch for meteors for awhile. That only costs you time and effort. No equipment needed.

I've got mixed feelings about astro apps and phones/tablets. Sure their handy but I often see people looking at it instead of the night sky. While your looking down or trying to move your device around to orient it a meteor goes overhead. But you missed it jacking with your phone.

Also your night vision is affected by that phone/tablet screen - every time you look at it your pupils constrict letting in less light (unless you put a red filter over the screen). generally it takes 20 minutes for your eyes to become adapted to the dark. And 3 seconds looking at a bright screen wipes out that adaptation.

Re: So You Wanna Buy a Telescope: Advice for Beginners (2015)

#85

Post by dang »

lake99 wrote: post #28

The advice here seems dated, even for 2015. Here's my advice: 1. Install an astronomy app on your mobile phone. Start with free ones, and see where it leads you. I recommend Skeye. This is good for going out by yourself and looking up things you see in the sky. For a PC, Stellarium is the best I have seen. 2. Get a camera capable of taking long exposure RAW photos, and get a tripod. There is so much hidden within the…

> Fuck off.

Please don't spoil your otherwise substantive comments by breaking the HN guidelines like this.

https://news.ycombinator.com/newsguidelines.html

https://news.ycombinator.com/newswelcome.html

Re: So You Wanna Buy a Telescope: Advice for Beginners (2015)

#86

Post by lake99 »

dang wrote: post #85
lake99 wrote: post #28

The advice here seems dated, even for 2015. Here's my advice: 1. Install an astronomy app on your mobile phone. Start with free ones, and see where it leads you. I recommend Skeye. This is good for going out by yourself and looking up things you see in the sky. For a PC, Stellarium is the best I have seen. 2. Get a camera capable of taking long exposure RAW photos, and get a tripod. There is so much hidden within the…

> Fuck off. Please don't spoil your otherwise substantive comments by breaking the HN guidelines like this. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newswelcome.html

It's too late for me to fix my comment. I'll tone it down next time.

Re: So You Wanna Buy a Telescope: Advice for Beginners (2015)

#87

Post by dang »

lake99 wrote: post #86
dang wrote: post #85

Earlier quoted context omitted.

> Fuck off. Please don't spoil your otherwise substantive comments by breaking the HN guidelines like this. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newswelcome.html

It's too late for me to fix my comment. I'll tone it down next time.

Thanks!

Re: So You Wanna Buy a Telescope: Advice for Beginners (2015)

#88

Post by Roboprog »

Roboprog wrote: post #2

I've had several small telescopes, but my favorite turned out to be my first: a 4.5 inch newtonian reflector on an (no motors) equitorial mount, with upgraded 35, 25 and 10 mm focal length plossel eyepieces. A small refractor on a camera tripod is too frustrating, and a small cassegrain on a computerized mount often is too much fuss to align and set up.

Explanation: an equitorial mount has an axis that points at the north star (Polaris, or more accurately, the celestial north pole). One you learn to set it up, it's pretty easy to just "eyeball sight" over the shaft-bearing at Polaris and call it good enough. When the planet or other object you are looking at drifts west, you turn a knob a little bit and it is re-centered.

Plossel eyepieces have 4 lenses, vs the 3 in a "Kelner". Minimal "rainbows" (chromatic aberration), and you don't have to smash your eyeball (or worse, glasses) onto the lens to see (eye relief). There are better eyepieces. Be prepared to spend at least 4 times as much, though.

The 35 mm focal length gives you the widest field of view in a standard 1 1/4" wide eyepiece, so you can actually find anything at all (and brightens dimmer objects), then, you can swap other eyepieces in the same series ("parfocal") without refocusing (much) to get higher magnification - 10 mm is the highest in my set.

Re: So You Wanna Buy a Telescope: Advice for Beginners (2015)

#90

Post by aortega »

madaxe_again wrote: post #64
aortega wrote: post #29

I disagree with the astrophotography thing. Even with a telescope your human eyes are limited to planets and the moon, that's it. Forget about seeing galaxies with the naked eye, unless you have a 1-meter diameter telescope. All other objects are basically points of light. Artificial satellites are really fun to see, but also points of light. But a 2006 DSLR (EOS400) that I found in the garbage, connected to a cheap…

There's astrophotography and then there's astrophotography, however - and you get drawn deeper and deeper into it. I have a few scopes, but mostly use an 8" celestron schmidt-cassegrain - it's a decent all-rounder for astrophotography, particularly as I mostly do deep sky stuff. I started with a simple T-adapter and a DSLR, and of course, you start as you describe playing with the exposure, the iso - but then you wan…

I just went straight to the cooled CCD/C11/hyperstar and don't repent. I would like a better mount though, but my EQ6 is just fine. Now I actually need a smaller scope :)
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