New Mag!

[ManintheMoon]

Hi everyone!

Yesterday my Dad bought me The Australian Sky and Telescope magazine and Mum has also got me a subscription with the free moon phase map and CD. (YAY ME! :2thumbs:) It is so interesting! It has also taught me a few words that you use a lot although I am wondering what a Barlow lens does (and do I need one?) I have been looking at the moon and stars with my little binoculars but can't wait to buy a 8" dobsonian like you said (but I have to save up yet)

I also want to say thanks to Paul for saying hello and that I would like to go and look through the school telescope soon.

One other question too. My brother (we are twins) was wondering if anyone could tell him if there are any forums or magazines for kids about photography because he wants to buy a camera and we are having trouble finding a forum which might be good for kids to go on too (like iceinspace!) I thought someone might know because you take photos through your telescopes.

Thanks again.

ManintheMoon

[dpastern]

A barlow lens magnifies what an eyepiece can deliver in terms of magnification. You can get barlow lenses in different strengths, 2x, 3x, 4x, 5x, you can even get zoom barlow lenses! A 10mm eyepiece with a 2x barlow effectively becomes a 5mm eyepiece. Optical quality will suffer to some degree, since there's more glass in the path. As usual, less is more.

For photography, I'd recommend:

http://photography-on-the.net/forum

Whilst it's a Canon site, they're happy to accept other camera users and there's plenty to learn.

Hope this helps.

Dave

[ManintheMoon]

Thanks Dave for the explanation and for telling me about the forum. My brother will have a look at it (when I'm finished here :D)

P.S I just found the glossary page :doh: and I will be reading a lot!

ManintheMoon

[ngcles]

Hi ManintheMoon & All,



Thanks very much for your kind comments about Australian Sky & Telescope. I'm glad you found it interesting and useful. You'll also find this place (IIS) is brilliant to find help on a whole range of topics to do with your binoculars and what to look at and when the time comes, a 'scope.

Don't forget to ask lots of questions, you won't go long without some sort of an answer here.

In basic terms, you should think of a Barlow as being a bit like a "pre-amp". It goes into the focuser in front of the eyepiece. The eyepiece then slips into the back of the barlow. Many, if not most barlow lenses provide a x2 amplification so an eyepiece that normally gives x100 magnification with a given telescope, will now give x200. Some specialised barlows give x3, x4 and x5. There is a down-side though. That increase in magnification means the size of the field (the sky you see inside the eyepiece) will halve in diameter (or quarter in area) with a x2 barlow.

But remember this: magnification isn't everything. It actually describes very little about how a telescope is performing. The true "power" of a telescope is the diameter of the main mirror (primary mirror) or lens collecting the light. Never buy a telescope based on how much magnification it can give. You can make any telescope magnify any amount just by changing the eyepiece or eyepiece/barlow combination. There is a practical limit to how much magnification a particular size telescope can handle. To calculate it, for most purposes, it is the aperture in inches x40. So with an 8" the practical limit is 40 x 8 = x320 (or thereabouts).

Most of us do most of our observing at low and medium magnifications. High power (magnifications) is reserved for really small bright objects like planets and planetary nebulae etc.

Barlow lenses are a good accessory to own because they make each eyepiece in your collection do double duty -- but it is important to get a quality barlow because a poor one will degrade the image quality greatly.

Hope you have a good time here and keep saving for that 'scope! (Christmas isn't that far away) If you have an astronomical society nearby, it is a very good idea to join up where you can meet other amateur astronomers and look through lots of telescopes. There is a listing of amateur societies on this site somewhere but I'm too tired to look for it at the moment ...


Best,

Les D

[Nightskystargaz]

Hi,

I've been getting S&T for over 45 years, here in the states, it is one of the best Mag. around.

Thanks,

Tom

[stephenb]

Welcome ManintheMoon :thumbsup:

[seanliddelow]

I saved up my money and now I have brought a telescope bigger then my schools! Camra house sells a 12 inch dob for $1200. The 8 inch dob may cost this much if you buy from somewhere else.

Welcome to Ice in Space:welcome:

[hulloleeds]

Andrews sell the GSO 12" dob for 999

(though around 100 shipping)

[seanliddelow]

I like the skywatcher one because its retractable.

[[1ponders]]

Hi ManintheMoon.

I'm not sure if I sent along the link to the Observatory or not so here it is again. Check the Bookings and Courses page for details.

http://mapletonss.eq.edu.au/mapletonobservatory/

[hulloleeds]

1200 for the collapsible skywatcher 12" is ultra cheap. Never seen it that price anywhere.

[seanliddelow]

I know its sells for that at camera house. I think mine was the last of the old shipment however so i was lucky to get it so cheap.

[erick]

With the upwards movement of the dollar over last few months, new shipments may be cheaper?

[hulloleeds]

Aye, still, telescopes don't strike me as the type of thing that fly off the shelves, got to get rid of the old stock before bringing those prices down. With Christmas coming (!) I doubt things will improve until Jan.

[ManintheMoon]

Hello again!

Sorry I haven’t been able to reply but my family is travelling at the moment and I have to share the computer with Mum and Dad when we get mobile signal on the laptop. :rolleyes:

I’d just like to say thanks very much to Les D from the AustS&T mag for his very interesting reply which has been really helpful! :thanks: I can’t wait till I get the next issue soon!

Thanks also for the welcome to the forum and hope to catch up with Sean and some other kids here when I get back home in a few weeks to my own computer!

Bye for now!

ManintheMoon

[seanliddelow]

There are 3 "kids" I know on IIS
TJD- Year 8
picklesrule - Year 12
seanliddelow (Me)- Year 9

[PCH]

And MattyP - he's a youngster as I recall :thumbsup:

[picklesrules]

Hey maninthemoon

thought id join in and say Welcome !
so Welcome :D haha
This site is wiked, when ever i have a problem i come on here and ask and theres always and expert to give us a hand :D

Yer like sean said im in Yr 12 so its good to see some other kids on here lol i don't feel so weird haha