astronomy & astrophotography for kids

hi all

i'm just after buying my first telescope to use with the after school STEM club i've set up in the primary school i teach in. astronomy is something that i've always wanted to get involved in so this is a great opportunity for me to learn and then be able to teach the members of the class.

so i bought a second hand meade newtonian telescope ldx75 6" with a 15mm eyepiece. i am looking to get into astrophotography as i think the visual element will really pique their interests, being able to print off a picture of some nebula or planet would be fantastic for them!!

so i know i need to get a few things so i'm hoping to get some pointers here. i need a powerpack for the goto mount, where would be the best place to get this?? i was told to get a x2 barlow and some more eyepieces, what would ye recommend and again where would be a good place to get these?? and lastly to start astrophotography, do i just need a webcam and a laptop or would a camera do??

thanks!!

Hi, and welcome to IFAS

It is great that you are planning to pass on the knowledge you gain about astronomy to your pupils.Kids love looking through telescopes, especially at the Moon and the major planets like Jupiter and Saturn.

I have to tell you that I know very little about astrophotography, but there are a few experts on here who will be able to tell you more. What I can tell you is that it is a steep learning curve, and there is a lot more to it than meets the eye, so to speak. In many ways, astrophotography is a completely separate hobby to observational astronomy, and it can be a drain on the wallet if you are not careful.

However, I can maybe give you a few general pointers. The telescope you have bought is a well-regarded instrument, which has now been discontinued. I would strongly advise you to contact your local astronomy society, who will be more than happy to help you to get the most from the telescope. Since you are planning to pass on your knowledge to the pupils in your school, I think this is especially important. When you know how to align the telescope properly to the Pole star, and set the go-to, it will be much easier and quicker to find objects in the sky. Once you find the object using the go-to, the telescope will track it in the sky for some considerable time. The more accurate the initial go-to, the longer it will track before the object starts to move out of the field of view.

As for equipment, I am not sure of the focal length of the telescope, but I suspect it is probably around 750mm, and I will use this focal length for the purposes of this reply. This means that the 15mm eyepiece you got with the scope will give around 50 times magnification (expressed as 50x). A 2x barlow, used with that eyepiece, will give 100x. (If I am wrong about the focal length, then the formula to find the magnification is - focal length of telescope divided by focal length of eyepiece = magnification. The focal length of the telescope will be given somewhere on the telescope, usually on a little plate near the eyepiece holder))

The higher the magnification, the larger the object being viewed will appear, which might seem obvious. But, with higher magnification, the object will also appear fainter, especially extended objects like galaxies and nebulae. Also, the higher the magnification, the quicker the object will pass across the field of view (in an un-driven telescope).

Many people who do not own telescopes, and know nothing about them, assume that the reason astronomers use telescopes is to get as much magnification as possible. This is untrue. The purpose of an astronomical telescope is to make faint objects brighter, so that they can be seen more clearly.

I would advise you to purchase an eyepiece somewhere in the range of 25mm as a first step towards your eyepiece collection. An eyepiece of this size will give you 30x, and will allow you to find the object you are looking for more easily. At this magnification, the object should be quite bright and easy to identify. You can then centre it in the eyepiece, and move on to higher magnification after that. As mentioned earlier, the telescope will track long enough to let everyone have a good look.

So, a 25mm eyepeice, your 15mm, and a 2x barlow, in a 750mm telescope, will give a magnification range of

25mm - 30x
15mm - 50x
25mm + barlow - 60x
15mm + barlow - 100x

Alternatively, you could buy an eyepiece of around 8mm (approx 94x), and forget about the barlow.

For eyepieces and other equipment, you should contact these guys, who will be more than happy to advise you. They can supply a power tank for the telescope, and the cable to connect the two.

www.ktectelescopes.ie/

Good luck

Hi,

Welcome!

Powerpack. lidl/aldi have them from time to time, and somewhere like Halfords might have one as well. And as Stevie says the guys at Ketch will be able to help also.

Astrophotography: Yep it's a steep learning curve and you'll always want to buy something new! I'd advise you to start with whatever camera you have access to at the moment and see how you get on. That scope and mount, once setup properly (the 'polar alignment' bit in the manual is very important!), is well capable of doing basic astrophotography. If you have access to a digital SLR camera that would be ideal, you can get an adapter that will let you attach it to the scope and basically use the scope as a big lens, and a 30 second exposure will be able to get images of the Orion Nebula for example. You'll also be able to get a shot of planets with a shorter exposure that should let you make out the main cloud belts on Jupiter and see rings around Saturn. You can also 'piggyback' a camera onto the telescope, this will let you take longer exposures of constellations, which you could then use to teach the kids their way around the sky, something about the brighter stars, and the mythology behind the constellations. It's hard to advise with astrophotography as there are so many directions you can go and so many things you can buy hence suggesting you try using what you have and then see what you think you need next.

If you have a club anywhere near you get in touch with them. They will be happy to talk to you and you can bring your scope to an observing night and I'm sure someone will let you try out other eyepieces and give you tips on astrophotography. And of course feel free to ask questions here.

You've a great scope for starting out with all this. I started getting into astrophotography with it's predecessor the lxd55 (10") with a film camera!

Cheers,
~Al

Hi Ballen,
Congratulations on your new telescope. There will be a bit of a learning curve ahead. but check out your local bookshop. There is a "Sky at Night" collectors edition magazine in bookshops (try Easons) at present. For novice and more advanced astrophotographers. Its called the "Complete Guide to Astro Photography". Well worth the money.

John

Hey, welcome and congrats on your new project. The kids will love it. Lot of guys here already given excellent advice. Something which has already been mentioned, but i think is the best advice, is to get in contact with your local club. They will steer you in the right direction. Where abouts are you based?

Sean

thanks for all the replies!!

i'm based in cork so i will try and see what clubs are around. i think that a dlsr so might be the way to go to start with. i got a great view of the moon on friday night and even got some nice photos on my mobile although i know using the proper equipment would be a lot better.

the funds are tight enough with the club (as i'm buying other gear too for the different areas of STEM), are the eyepieces good value second hand or online somewhere?? and same with the powerpack, what would you be looking at to pay for that??

thanks again