What options / equipment does a newb need with an 8" Dobsonian reflector?

[MarkVIIIMarc]

Hello, I am a newb doing some shopping and am trying to make sure I don't do the equivalent of buying a car without locking doors!

My basic question is what options or equipment do I need to make sure any telescope I consider has and what are the best options?

My understanding is I want an F5 or greater numerically scope?

Is there a real difference if it takes 1.25" or 2" eye pieces?

Thanks in advance and may mother nature bless you with dark skies for your kindness

[iPeace]

I would suggest choosing a scope (focuser) which takes 2" eyepieces, as you can use a widely-available adaptor to use 1.25" eyepieces as well. There are eyepieces on the market which will fit both (basically a 1.25" eyepiece with a 2" barrel and a 1.25" protrusion) but there are also eyepieces which only come in 2" including some you might not want to miss out on, if not initially then later on.

[iPeace]

Here's a couple of videos on getting the best planetary views:

Top 5 tips for improving planetary views with your telescope

Observing planets: optimising your views

[bottletopburly]

Dont attatch a camera you will then be on a slippey slope lols it will be never ending

[Pete Presland]

4 hours ago, MarkVIIIMarc said:

My understanding is I want an F5 or greater numerically scope?

Is there a real difference if it takes 1.25" or 2" eye pieces?

The F5 or greater probably has been mentioned because the higher F value scopes are less demanding on eyepieces. What type of astronomy are looking to do ? Is it an all round approach or just the planets? The mount you chose is as important as the scope you will put on it. 

A 200mm dobsonian is a very popular choice these days, but does come with its limitations.

[Putaendo Patrick]

An 8 inch Newtonian reflector on a Dobsonian mount is an excellent choice for visual astronomy. In general there is not much difference in terms of quality between the major manufacturers. Probably in this size, a solid tube is more stable and will need less collimation (aligning the mirrors) - collapsable tubes however are more compact for storage and transport, if this is an issue.

With all reflectors, collimation is necessary from time to time (with a little practice this is not difficult), and you will probably want to get a Cheshire Eyepiece to do this. Cheaper laser collimators are probably not worth it! Many people often replace the standard adjustment screws with "Bob's Knobs" or similar (but this will depend on your telescope).

Most 8" reflectors now are fitted for both 1.25" and 2" EPs. The 2" EPs can be especially useful for wide views at relatively low magnifications. Normally you will get one or two EPs supplied in the box with your new telescope. Generally these are more than adequate to get you started, but they are not the best quality. Once you know your "favorite" magnifications, you will probably want to upgrade - but take your time!

An economical way to increase your range of magnifications is a Barlow which will effectively double or triple the power of any given EP. Thus 3 EPs plus 1 Barlow gives the equivalent of 6 EPs. Not everyone likes them though!

In theory an 8" telescope can handle magnifications of up to x400. Remember, though, that in practice this depends on viewing conditions. Unless you have a perfect dark-sky, x200 is often a more realistic upper limit.

Other useful additions and upgrades along the line include:

Dew Shield and/or heater to prevent condensation,

Better finderscope (Telerad, for example, are very highly considered),

Improved focusing

Stellarium is an excellent free computer program to provide maps of the sky customised to your location. Virtual Moon Atlas, also free, has excellent maps of the Moon. Both can be downloaded from the Internet. Many people also install sky mapping programs on their smart-phones or tablet, there are several very good free or paid options.

A red light torch is essential (red light does not affect your night vision). Either buy a red one, or simply cover an ordinary torch with red cellophane.

For comfort, many people have an adjustable observing chair. Those made especially for observing tend to be quite expensive, but you can use an ironing chair, drummers stool or make your own!

Filters are very useful for some specialised viewing, but there's no need to rush out to buy them at once. Some people do however like a Moon filter as it makes viewing much more comfortable. Correct solar filters are ABSOLUTELY essential, however, if you want to look at the sun - don't even think of any shortcuts!

[MarkVIIIMarc]

Thanks for the tips. 

Most interesting thing I found is my old desktop I'm typing on now runs XP so it is too dated for Stellarium lol.  The laptop is probably better suited anyway as it can be taken into the garage.

The Cheshire Eyepieces I see have a pretty good range of prices.  I was hoping there was only one to choose.

Oh, and thanks for the advice to keep the cameras away from the telescope! 

 

[Dave In Vermont]

Someone asked this a day or so ago. Anywho - I'd suggest one that comes with a RACI (Right-Angle Correct-Image) 8 X 50mm finder (to save your neck), and a good Crayford-Focuser. The best deal on these - with good optics as well - is a Zhumell 8" Dobsonian. Here's a link:

http://www.telescopes.com/pages/search-results?q=dobson&p=1

It may still be out-of-stock (wonder why?), but the free shipping makes up for that - in spades!

Dave

[MarkVIIIMarc]

22 minutes ago, Dave In Vermont said:

Someone asked this a day or so ago. Anywho - I'd suggest one that comes with a RACI (Right-Angle Correct-Image) 8 X 50mm finder (to save your neck), and a good Crayford-Focuser. The best deal on these - with good optics as well - is a Zhumell 8" Dobsonian. Here's a link:

http://www.telescopes.com/pages/search-results?q=dobson&p=1

It may still be out-of-stock (wonder why?), but the free shipping makes up for that - in spades!

Dave

Might be out of stock because it is popular!

You bring up a good point.  My toy refractor telescope does not have a Right Angle image finder and it is rather a pain.

Thanks for mentioning that

[Dave In Vermont]

Lordy! It also comes with a laser-collimator?! Now that wins a prize!

Dave

[Putaendo Patrick]

Dave:

"The Z Series is affordable, but that doesn’t mean it’s stripped-down. This telescope includes well over $100 in bonus accessories! It’s everything you need to have a great first night out and enjoy stargazing for years to come:

• 2” 30mm fully multi-coated eyepiece
• 25” 9mm fully multi-coated eyepiece
• 8x50 right angle finderscope
• 1.25” Moon filter
• A laser collimator to keep your optics in perfect alignment"

Not only the laser, a 25 inch eyepiece is getting pretty serious!

But it looks like a good deal - I've heard good things about Zhumell! I think they're a US brand for GSO.

[Dave In Vermont]

Actually my friend John (Lowjiber out of Las Vegas) told me about this - and he's a great guy. It really is a loaded package deal! Makes me wish my 200mm Newt needed replacing. I'd jump for it - typos excepted. Though I suppose I could find an ambulance-chaser attorney, and sue them,  for not sending the 25-foot eyepiece.....

Dave

[todd8137]

Great scope,choice if it was me a telrad ,and some free telrad charts of the Internet ,a dew shield and a mix of,low and high power ep's and that should keep you going for a while,but the best thing I could,advise would be learning the constellation s and what dso's they have in and around them trying learning the named stars in each one ,because you will be suprised when you have friends round and you start pointing out stars and what's in a constellation good luck 

pat