poss picked scope but what about ep's?

[jobe]

Hi you guys and gals

i've been looking to finaly get a scope after years of looking up.

i think i've settled on this one.

Skywatcher Explorer 200P DS OTA

with the eq5.

i want to manually find the goodies first to find my way around.

i may get it's slightly big brother, the 250 but flo recommend a Heq5 which is a little more than i would like to spend.

my problems come with choosing ep's.

1 do i need to buy 2" ones

2 is there a 2" to 1.25" converter to use either

3 does the ep fit first with the barlow on top or the other way round

4 any help in deciding which ep's to get. an excellent sticky on here suggests an 8, 16 and 25mm but what do all the letters after mean. don't want the cheapest, just nearly 'cos this hobby costs a fortune.

5 heq5 and eq5. as far as i can see the only difference is automatic tracking, negating the earths spin. i thought you can buy a kit for approx £100 to do this although the difference if the two is more than double this?

you can see why i'm a little confused.

this is my mate!!!

a bit of background.

i have a pair of 10*50 binos and stellarium which i go to view with but after only a few looks i want to see more.

thanks for reading and i hope some of you can help

Jobe

[Cornelius Varley]

1. Not really, 1.25" are fine.

2. The focusser is a 2" but has an adapter to take 1.25" eyepieces.

3. The barlow goes in first then the eyepiece fits into the barlow.

5. The difference between the HEQ5 and EQ5 is more than a letter.

The HEQ5 is a larger mount and is a scaled down EQ6 rather than a scaled up EQ5. The load bearing capacity of the HEQ5 is about 18Kg and about 9Kg for the EQ5. The HEQ5 is fitted with dual axis motors as you have mentioned and the EQ5 is unmotorized as standard.

Peter

[michael.h.f.wilkinson]

Letters behind eyepiece names are often the following:

SWA(N) = super-wide angle (about 68-72 deg apparent field of view)

UWA(N) = ultra-wide angle (about 82 deg apparent field of view)

The apparent field of view (AFOV) is important because it tells you how much of the sky you can see (true field of view or TFOV): TFOV = AFOV / magnification

These indication do not say anything about the quality, just about AFOV. Because you have a fast scope (low F/ratio) you will need better quality EPs, which can cope with the comparatively wide light cone. As you might expect, large AFOV, high quality EPs are expensive.

Some indications (Plossl, Kelner, HM, ortho, etc) denote optical design type, other indications are often abbreviation for brands (TS=Telescope Service, TMB = Tim Back, WO = Williams Optics). In the SWA section, I rather like my TMB Paragon (brand + type) 40mm, which costs about 270 EUROs over here, and the 30 mm is also supposed to be good. In the longer focal lengths, the Baader Hyperions are getting quite a good press.

Hope this clarifies things a bit

[Astro_Baby]

I would serioulsy advise against rushing it with extra eyepieces until you have had some eyetime in withe the scope. Eyepieces are notoriously a personal taste thing and wht suits one wont suit another.

Also beginners are oftem tempted to get the most powerful eyepiece in magnification terms and then find that they dont ever get to use it because conditions in the UK almost never allow very high power viewing.

Lots of beginners are a bit surpised to find that its the low power eyepieces that get used the most.

A SW 200 will have a 2" focuser with a 1.25" adapter. The supplied eyepieces are 1.25" fit and while not the greatest they are perfectly acceptable to start with. 2" eyepieces are mostly low power wide angle eyepieces. Higher power eyepieces are almost always 1.25" fit ( as a general rule ).

I'd really get some eyetime in first and see what you think you need based on experience with the supplied eyepieces.

[michael.h.f.wilkinson]

You are right of course, I used my "standard" Plossls (2x Celestron and 1x Vixen) 10, 26, and 36 mm with my C8 (at F/10) and a focal reducer 0.63x for wide field for more 4 years before adding the more comfortable (long eye-relief) Vixen LVs. By using the 10 mm I had realized its eye relief was the main problem, so I new what I was looking for in replacement. Only much later did I get the TMB Paragon, which was so much nicer than the other EPs that I started replacing them.

What can also be very useful is to visit a star part and have a look through other EPs to see the difference.

[acey]

Use the eyepieces that come with the scope. Learn to get as much as you can out of them, then think of upgrading.

The most critical factor is not the scope or eyepiece, it's the eye.

[russ]

Your scope will come with one eyepiece, a 28mm 2" 56deg. It should be of decent quality giving a really nice field of view. Normally Skywatcher give away 2 low to adequate quality eyepieces (25mm & 10mm) and a good quality barlow with their scopes but this time they have decided to give away one decent eyepiece.

Most people who get a scope for the first time will make a B line for the planets and the moon, unfortunately the 28mm is the wrong eyepiece for the job. You'll need another eyepiece or two straight away. It's an eyepiece for wide extended objects like open clusters, large galaxies, very low power lunar or just finding things initially.

I would say you'll need another two eyepieces to get some useful views from the scope. A medium power (12-18mm) is the most useful. And higher power (5-7mm) for the planets. These needn't cost a lot. There are some good quality Plossls available for minimum outlay.

Russ

[jobe]

thanks for all the help guys.

i am mostly interested in dso's although i know i won't see them as good as the photo's so the one that comes with the scope will definately get used.

i'll have a look around the site and maybe ask another few questions.

jobe

[jobe]

right.

looking at the posts above the opinions seem to be a little divided.

after reading a few more stickies and posts i may be getting somewhere.

although the supplied 28mm will be good for dso's, i think i'll need something like an 18mm so i have a bit more poke for planets, while not particularly my faves will need to be looked at. (especially Saturn)

could you guys recommend a good all rounder for this?

i can't afford the expensive stuff but say maybe £70 wouldn't be so bad as i could recoup some back if i decided to sell.

also what about a barlow? does everyone have one. the way i see it, one of these effectively doubles the amount of ep's you have.

thanks

Jobe

[michael.h.f.wilkinson]

As your scope is an F/5, I would go for a 5mm first. This gets you the so-called optimal magnification (200x for a 200mm aperture). I can use 200x in my scope on quite a lot of nights without "super" seeing. A Plossl is fine, but can be a bit annoying in regards of short eye relief. The Burgess TMB planetary EPs are better in this respect, and get a really good press (70EUR over here in the Netherlands, so it should fit in your budget). These should be a good long-term investment.

If you go for a 5mm, you might want to consider a 14mm rather than an 18mm, to fill up the gap between the 28mm and the 5 in a more even way.

A barlow is useful if it has decent quality, but opinions are (often vehemently) divided. They are a good way of making you money stretch further. I almost exclusively use my "barlows" (TeleXtenders and Powermates are not "really" barlows although they do the same thing) for imaging work.

[jobe]

If you go for a 5mm, you might want to consider a 14mm rather than an 18mm, to fill up the gap between the 28mm and the 5 in a more even way.

A barlow is useful if it has decent quality, but opinions are (often vehemently) divided. They are a good way of making you money stretch further. I almost exclusively use my "barlows" (TeleXtenders and Powermates are not "really" barlows although they do the same thing) for imaging work.

i thought a barlow doubled the mag of the ep so a 28mm with barlow would make 14mm but you recommend a 14mm also? is this right?

jobe

[michael.h.f.wilkinson]

If you get a barlow, a 14 would indeed be a bit superfluous. The 14 would be better if you do not choose a barlow or you could opt for an 18mm (as before) and a 10mm to fill the gap between the 18 and 5 (again if you do not choose a barlow)

If you have a 28, 18, 10 and 5mm you have most bases covered, so choosing either a barlow or a 10 mm would work.

[John]

Remember you will need to get a 2" barlow lens if you want to use it with the 28mm eyepiece. Sorry if you had already worked that out

[jobe]

Remember you will need to get a 2" barlow lens if you want to use it with the 28mm eyepiece. Sorry if you had already worked that out

yeah i'd got that one thanks. ( well steve from flo told me)

i've started another thread due to this one being a little old and the scope info isn't right, although the ep's will work ok with what i'll be getting

jobe