What do I buy?

[khalen]

Ok, so I apologise. You have heard this question a million times already in various forms. I am totally lost on what to buy. I am taking a university course starting in Oct to get a physics and astronomy degree with the OU.

Now, I am going to want to get my first scope but I am totally lost as to what to get. Initially I am interested in looking at planets and Saturn with its rings is a must of course, and nebulae.

I believe a reflector is the ?best? but am at a loss as to what size I would need. I have tried looking at others' posts but only get more confused. What size would you guys suggest would be the SMALLEST I should go for.

I intend to purchase the best quality I can afford and that is likely to be around £750.

Your suggestions would be very much appreciated.

[Bizibilder]

A reflector of 200mm or so is usually considered to be a good "all rounder" - say a SW200P on an EQ5 with or without goto?

[Ad Astra]

Hello Khalen,

Going for the science degree, eh? Just happens to be my area as well!

The workhorse telescope for my astronomy program is the 150mm f/8 dobsonian. Lightweight, rugged, compact - it is easy for one fellow to transport, use, and store. It sets up literally in less than a minute, and stores just as quickly - very important for students (and professors!) with busy schedules. I have 12 of these (from Orion USA) in service in my classroom - some have 12 years of service on them - and all work terrific - just as well as the first day I got them. Considering they have over a decade of use by teens who don't actually own them... I don't think I have to go on about study and properly built, do I?

You may wish to invest in an "intelligent" scope - one that has a 'passive computer' on board. These do not track the sky, but will help you point your scope to any target you wish, and can help identify what is in your eyepiece, too. (These rigs usually add about $150 to a scope in the USA, your local dealer can help you out.) Keep in mind these don't track the sky, but they DO require you to align them precisely in order to work properly - and that requires some recognition/knowledge of the sky and constellations & stars by name. The nice thing is that the scope is perfectly usable without activating the computer when you just want to grab and go see the Moon! Not buying a tracking or "GoTo" scope will save you several hundred.

Take the balance, and invest in a couple of eyepieces - usually one larger and one smaller focal length than those that come with the scope. A basic moon filter and a barlow lens are a good idea for beginner kit as well. For two eyepieces, a barlow and a filter - about $180-250 here. Don't forget a case to carry them all in!

You can probably also add a decent pair of 7x50 or 10x50 (your choice) for about another $100. These will be invaluable for you when you are first learning the sky and the constellations, as well as the location of the 100 or so brightest deep sky objects (nebulae and star clusters mostly, plus a handful of galaxies) and lots of nice double stars.

I think I've spent your $750 - but you will have an excellent kit and a great start on any basic lab work / research you want to do. This isn't an astrophoto setup at all - but it is an excellent setup for the student who is serious about astronomy and physics.

There are two options you may wish to consider.

1. Going to a 200mm f/6 (8-inch) telescope. This adds about $125-150 to the basic cost, but effectively doubles the deep sky capacity of the telescope. You can also make yourself an inexpensive aperture mask to transform it a wonderful 100mm (off-axis) f/12 for planetary and lunar work. The disadvantage is that you effectively double the mass and size of the basic unit. If space at home or in the car is a consideration - consider carefully before you go this route.

2. Going to a 90-100mm refractor on an equitorial mount. You may be able to get into a GoTo system for this price point, and a refractor is excellent for lunar and planetary work - but you will sacrifice a tremendous amount of deep sky capability. (A 100mm refractor has roughly 1/3 the light grasp of a 200mm reflector.) This system looks very sexy on the tripod - much more what people think of when you say: "I have a telescope in my flat!" Once again, think carefully before you take this option!

Lastly - before you buy - take a trip to the local astronomy club and have a chat with them. There will be lots of people there with kit very similar to everything I've mentioned. Better yet, join them for a public star party where you can actually put your hands on and try the gear. See them setting up and how much work it is for one rig compared to another. Above all, see how BIG they are in person!

I hope that helps!

Dr. Daniel Barth

Associate Professor / Astronomy - Physics

Mt. San Jacinto College

San Jacinto, California

[khalen]

Thanks guys ... a lot for me to think about Dr Dan. Bizibilder, I will look at SW200P along with other 8" mirrors.

[ollypenrice]

Very good answers above. You have the budget for a decent scope. Enjoy the course. I have done similar ones with the UCLAN/LJM/Jodrell bank consortium though not to the full degree level. One day!

Olly