So what do I "actually" need?

[Tube Screamer]

Hi guys,

So I've just purchased my first telescope (a Skywatcher 250px classic dob), and after looking at what accessories I am going to need to form a decent "all round" kit, I am getting somewhat confused with all the various options and price brackets of what is available. 

Before I purchased the scope, I was advised that the supplied kit eyepieces that come with the 250px are rather poor, and whilst good enough to get me started, I should look to replace them sooner rather than later to get the best from the telescope.  I was also told that the 250px does not work well with poor quality eyepieces, and so after searching the web for various eyepieces, I am now completely confused with all the various sizes and price points available.  I mean, you can literally pay anything from <£30 all the way up to £500+ (more than I paid for the entire telescope).  So at what price point does a "decent quality" eyepiece start?  Surely I don't need to spend up to £500 per eyepiece.... I'm assuming those eyepieces would be the equivalent of buying a pair of Leica binoculars?

So regarding the eyepieces, I was hoping to purchase 2 or 3 decent quality items, which would allow me to get some good views of both planets and DSO's. 

I would also appreciate some advice on Barlow's, such as; do these things also need to be of high quality (do they actually contain a lens?), and what size/sizes should I require for a decent beginners setup?

One final accessory I wanted to ask some advice about was filters.  I was reading about them and found that they're so many of them to consider, each with its own specific purpose, such as filters for light pollution, filters for viewing the moon, filters for viewing DSO's, no end of coloured filters for enhancing different parts of different planets, polarising filters etc, that in the end I had no idea what I needed.  Do I need them all?  Would there be a small collection of 3 or 4 filters which would be a decent "all round" set to collect to cover both planets, deep sky and moon? 

Also I found that, as with the eyepieces, the price (and I suppose quality) of the filters also varies quite a lot.  So does the quality of a filter affect the scopes performance a great deal, and if so, what sort of price point/brand should I be considering?

So to summarise;  If any of you would be kind enough to advise me on a decent starter set of eyepieces, Barlow's and filters suitable for my new Skywatcher 250px classic dob, I'd be very grateful.

Thanks for taking the time to read

Russ

[Marv-in]

I too am trying to figure things out. From what I can tell, the better the EP the finer the detail your eye will see which in turn will make the object look bigger and better. The way it was explained to me was how you look at a bird or some other object in the distance it appears bigger than it really should be because your brain is building up from lots of smaller images.

Having said that, I went with the celestron accessory kit which had ok lenses and filters. What I can see is awesome, and if I upgrade, probably see even more. I relate it more to photography, its all about the optics. I mean a nice DSLR is $300 and a sweet lense is $500, $1000, or more! So I went for the best deal I could afford because I needed more than just the 40mm EP my scope came with.

Hopefully that makes sense and someone can correct me if I am wrong.. even if it doesn't really answer your question.

[Qualia]

Screamer, if possible take your time. Seriously. There's no hurry

Try to appraise your gear first and then you'll have a better idea of where you want to go and how exactly you want to get there. You ought not to upgrade or buy anything until you know you are missing out on something that is essential to your observing sessions and just as importantly when you know how it can be improved upon and bettered. If you haven't even used your scope, or only a little, I can't see how you're going to make a sensible and informed decision.

It's my own personal prejudice, but I've found my most used EPs in my 10" f/5 for general DSO viewing have always been around that 120x mark and then backing off from that with something around 90x. With a low power 24mm, you've pretty much got your bases covered.

If you got yourself a decent barlow with just these 3 EPs you'd have a spread like this:

24mm = 41x, 82x.
12mm = 83x, 166x.
8mm = 125x / 250x.

You might think - and correctly - that the 80x has been doubled (in both the 24mm and 12mm) and you're right, but I'm figuring that the 12mm barlowed might be very useful for Saturn, Jupiter and Lunar work. It's only a rough guide, but you should get the idea.

The lower mags would be nice for general hunting and framing largish objects, the middle ground for globs, galaxies, nebulae, the higher powers for Saturn, Jupiter and Lunar work and the 250x for those exceptional nights with Saturn or the Moon. If you got yourself some Baader solar filter, your 40x would also be fine for white light sun observations. The only snag in this plan is not knowing whether planets are your thing. If they were, you might want a bit of a spread of eyepieces around 130x to 200x.

Needless to say, there's no hurry. You might find you don't like using a Barlow, you might find you need dedicated eyepieces etc, but at least you've got some kind of working map to guide you.

BSTs and X-Cel LXs (at FLO) come highly recommended and as you can see, with just the purchase of one or two more eyepieces and the Barlow, you'll have yourself a nice set up for this Spring and Summer . Other than that, Tele Vue and Pentax also come highly recommended but these are a lot pricier. 

I really can't say a lot about filters. I don't generally use them, but you might find a #81A nice addition from time to time on Jupiter, something like a UHC for certain kind of nebulae, a Baader solar film for viewing the Sun in white light. I do have a Moon filter but have never really used it, finding that upping the magnification a little does an excellent job

Final thought...

If I were you I wouldn't spend a penny on astro-gear for next 4 or 5 serious sessions. Start using a little journal, or rely on mental notes on what you like viewing and with what EP in your collection. Do this for a few sessions and I reckon you'll be able to make a more informed enquiry. You may find you need a decent finderscope, a red dot finder, a chair, an atlas etc and so some of the EP and filter money needs to go into these things.

Hope this helps

Hope this helps a little

[haitch]

The other thing that pushes EP prices up is the angular field of view. Eyepieces likeTelevue Naglers (82 degree) and Ethos (100 degree) are far more expensive than their Plossls. It's down the design complexity, need for exotic materials and special coatings. I have to say I do like wide angle EPs especially for use in my dob as for a given magnification you get more time between tracking nudges. It also allows you to see more surrounding sky putting the objects you view into a sort of context.

Anyway, like other say, don't jump in with both feet yet - see how you get on with what you've got first.

HTH

[Langy]

Agree about not buying anything too quickly. As you have found there is a wealth of items out there at all sorts of price ranges. You really need to learn to use the kit first. Being able to find objects in the sky is far more important than seeing them close up. For me a finder scope and later on the Binoculars were by far the best buy over the EP and Barlows I bought. I'm still struggling to find objects now so having lots of EP's and filters would be of no benefit.

On my scope the stock EP's the wider 20mm is great to use and the shorter 10mm was the one I replaced with an 8mm.

My 20mm gives my 32x mag and in fact that is too much on some objects where you can't see them all at once which is where the bins even outdo the scope.

[AlexB67]

Adding to the already excellent advice .  If you wear glasses you may want to think about upgrading something around the stock 10mm eyepiece sooner than later. it is quite tight for seeing the entire view since your eye cannot get close enough to see up the edges of the eyepiece.  You will want to look at something with good eye relief, ( the distance your eye needs to be from the eyepiece to see  through it comfortably that allows you to  see the entire view.  

I wear glasses day to day but I have no astigmatism so I tend to mostly observe without them now, except when using low power and searching the sky and looking through the rigel quikfinder, I'd be lost without my glasses looking through it otherwise being short sighted

As Qualia said, one of the first things you may find you will need is a red dot finder of something similar like a telrad or rigel quickfinder that projects circles or a dot onto the sky. Using the finder scope by itself can be very hard to know where to initially point the scope, I find anyway. The red dot is used to zone in and align on a region, then the finder can be used to fine tune to your target, that is how I usually do it.  

Good luck

[AlexB67]

Something I forgot to add, you will want something for collimating the scope too if you already have not got something.  something like this will do the trick

http://www.firstlightoptics.com/other-collimation-tools/cheshire-collimating-eyepiece.html

This instrument being fairly short focal ratio at f/4.7 really benefits from good accurate collimation, but once done, it does not need doing a lot at all I find with the flextube model anyway, so I expect the solid tube is the same if you own that one.  When you move the scope a bit and bump it around in a car it will need collimating again after you take it on a journey, so a collimation tool is something you will want to add to your arsenal sooner than later.

[AndyWB]

Qualia's advice is, as usual, excellent, but I'd also highlight his suggestion of a red dot finder of some description (basically, yes, a Telrad or Rigel) I find it much easier to use - at least to get in the right area of the sky with - than the finder scope. I'd recommend one of those before you think of new eyepieces, etc.. It's frustrating not even being able to get in the right region of the sky, which is what I was finding.

Filters - don't bother yet. Eventually, you'll start thinking about them, but really, don't worry yet, you don't need them.

Oh, and if you've not got one, a really warm jacket is very useful. My down jacket is my most important bit of kit. Seriously.

[Astro Imp]

You have already received excellent advice about not rushing out to buy eyepieces.

How are you going to navigate the sky? Do you have a good star atlas? How about Stellarium?

For an atlas many of us on here use Sky & Telescope's Pocket Sky Atlas, get it from Amazon.

Stellarium is a free planetarium program:- http://www.stellarium.org/

Have fun and let us know how you get on.

[wenskir]

I'm so glad with these kinda topics. Considering I'm collecting all the info I can, I just ordered that pocket sky atlas !

[rwilkey]

I'm so glad with these kinda topics. Considering I'm collecting all the info I can, I just ordered that pocket sky atlas !

Well done Wendy, you will find it very useful!

[wenskir]

Thanks ! I get a lot of info here !

[Moonshane]

as hinted at above, you could spend £500 on an eyepiece and then not be able to find anything. I'd be cautious about spending lots but budget for :

red dot finder (I use telrads)

collimating tool (I use a cheshire)

right angle correct image finder

seat

decent star map

red torch (dim)

the above will enhance your experience more than additional eyepieces.

then start on eyepieces. £50-60 will get used Televue plossls - hard to beat - if you wear glasses buy only down to maybe 20mm if not they are all good. you won't go far wrong, a barlow might be helpful too. quality not critical in the early days at least

[Toymaster]

Useful thread for me as I'm a newbie with a DOB and standard EPs and Finder.

What about a Zoom Eyepiece? Any recommendations that are affordable (Less than £130)?

and finders: Rigal - higher up than the Telrad - or the Baader

 http://www.firstlightoptics.com/finders/baader-40mm-super-sky-surfer-v.html

Already have the Baader collimator which I'm finding good for me.

Sorry if I've hijacked the thread....

Ade

[Marv-in]

A seat!! Get one of those first. Also, when I was looking at the moon without a filter... i threw my sunglasses on, cuz I wear my sunglasses at night so I can, so I can .... sorry

[ronin]

Ignoring to an extent the idea of what do you need immediatly I tend to suggest thinking of 4 eyepieces, and since you have a newtonian you will sooner or later need a collimator.

Eyepieces I tend to go by the scope's f number - get one that is the f number of the scope - in your case I guess f/5 so a 5mm EP, then get one a bit longer for when the previous is too much for conditions. In general that means 7mm or 8mm. After that something for a wide view - 25mm or 30mm depending on the EP design. Then finally something mid range say 15mm.

The not quite so high magnification options are based on the 2 main mid price EP = BST Starguiders or X-Cel's.

I do not really go great on barlows, so that is your decision.

If you swap finders then first thing to do is decide which alternative you want and if it works for you. Have read of people trying 3 or 4 before finding the "one" for them. Because one person raves about a particular one doesn't mean you will get on with it.

Plossls will I suspect not work well on your scope except for the TV plossls, the scope is a bit too fast for them. What eyepieces came with the scope? Were they plossl's? Sometimes on the 250's they are supplied if so they may be reasonable ones.

[Astro Imp]

As Shane said above a seat makes a huge difference, you won't realise how much until you sit comfy at the eyepiece and relax.