Eyepieces

[Mathyas]

Hi guys,

Im new to astronomy and i would love to here some advices which BUDGET eyepieces should i get for a 8" dobsonian. For planetary and deepsky observing.

Not anything too expensive.

Thanks!

[ronin]

The 8" Dobsonians tend to be f/6.

You have the option of something like the Vixen NPL Plossl's but got planetary work at shorter focal lengths these may not prove a usable option. THe eye relief gets small. FLO have tem for around the £40 area (+/-£5).

Generally the recommended option are athe BST Starguiders (£49), minor drawback is the 5mm to 8mm step at the lower end, I filled it by buying an Altair Lightwave at 6mm for (now) £55. Starguider came from Alan at Skies the Limit, the Altair one was from Tring Astro - Altair is an obvious source however.

The Staguiders are the same as the TS NED eyepieces, same eyepiece from Barsta with assorted names and brands on the side. Just in case TS are easier to purchase from.

Maybe check out the Celestron X-Cel LX options. Perform similar to the BST's but here they cost a reasonable percentage more so the BST's sort of get the greater number of purchasers.

I would suggest the 6mm Altair, 8mm BST and then I suppose the 15mm BST and the 25mm BST. 4 required but should cover most situations. I have the full set of BST's. As I guess the 5mm may be a bit too short that leaves 5, if you get as indicated then you will have 3 out of 5, you could easily just get the other 2 to have an almost full set and so equiped for everything. Even once or twice a year the 5mm may work for you.

[Jimtheslim]

How much are you looking to spend exactly? Some people's idea of 'budget' might mean buying an eyepiece for £100 rather than £350.

For less than £50 you can pick up Plossls. these are usually around £20-£30 second hand. Even better would be an ortho for between £30-£40 second hand. Definitely worth the extra £10 in my opinion.  Both have tight eye relief, especially at higher magnifications and a smaller field of view at around 50 degrees. However they are similar in these respects to the stock eyepieces that come with many scopes so if you don't have too much hassle with eye relief looking through those then plossls and orthos are a good option.

As stated above the BST's seem to get good reviews for their price. I haven't tried one but I do have a 10" f/4.7 reflector and my 7mm Celestron Excel LX performs rather well on planets. It's a bit more than the eyepieces I mention above but gives you a wider field of view (less nudging the scope if it's manual mount) and more comfortable eye relief.

[Mathyas]

Well,

Im a student so I dont have too much money. Do you suggest to save more money to buy more expensive eyepiece? Or to buy something like Sky-Watcher's Plossl?

Sky-Watcher's Plossl are around 15 pounds in my country. But i can save some money and buy one eyepiece at the time. What do you think would be better?

[John]

Hi and welcome to the forum

Having used quite a lot of eyepieces (low cost and expensive) I feel that the following offer the best step up in performance, per £ spent, from the "stock" eyepieces supplied with scopes:

- GSO plossls. These can also be purchased in the UK branded as "Revelation".

- Vixen NLV plossls.

- BST Starguiders / Explorers (old name)

- Baader Classic Orthoscopics (6mm, 10mm and 18mm)

- Maxvision 68 degree range (16mm and 24mm - used or ex-display)

All these have a retail price of £50 each or less. The GSO / Revelations are around 50% of that a less again bought on the used market.

If you are interested in a barlow lens to expand your eyepiece range then the GSO / Revelation 2.5x is a good performer at around £35 new or the Baader Q-Turret 2.25x Barlow is excellent for £45.

The above does not imply that other brands / ranges are not good but these are the ones that I have owned and tried in my scopes which include a 12" F/5.3 dobsonian which is more demanding on eyepieces than your 8" dobsonian, assuming that it's an F/6.

If you wear glasses when observing then the BST Starguiders may be a better choice because they have longer eye relief which makes life easier when wearing glasses.

 

 

[Alan64]

If you plan on observing for quite some time, and for years to come, and we do hope so, it's best to build up a fine and useful set of eyepieces and accessories one piece, or two at most, at a time.  That way, you won't have to get them later.  But that doesn't mean that you have to break the bank.  The GSO and Vixen NPL lines of Plossls are a good choice.  Know that Plossls, however, have tight eye-relief shorter than 10mm, like a 6mm, and where you have to place your eye right up to the eyepiece to see the full view that the eyepiece provides...

The views through this Vixen NPL 6mm are wonderful...

...but I have to place my eye right up to it to see the full view.

Your 8" Newtonian has a focal-length of 1200mm.  An 8" aperture is theoretically capable of powers up to 400x, but the atmosphere and an average collimation limits that to about 200x on most nights, perhaps even less...

1200mm ÷ 6mm = (200x)

That's about the highest power as you'd want to go, and where the images would be sharp and clear, with a bit of luck and perseverance.

At 200x, however, an object is going to race out of sight with a manual mount, and due to the very small part of the sky being observed, so you want as wide a view as possible to give you a bit of extra time to view the object before having to bump and nudge the telescope to reacquire it.

Teleskop Service, essentially right next door to you there in Germany, has a good selection of eyepieces; not great, but not bad...

http://www.teleskop-express.de/shop/product_info.php/info/p159_TS-Optics-Optics-6-mm-Planetary-HR---1-25--Eyepiece--58---fully-multi-coated.html (200x)

For a lower power, but still high enough with which to view the planets...

http://www.teleskop-express.de/shop/product_info.php/info/p153_TS-Optics-Optics-9-mm-Planetary-HR----1-25--Okular--58---voll-multiverguetet.html (133x)

If the 9mm is  too low...  http://www.teleskop-express.de/shop/product_info.php/info/p154_TS-Optics-Optics-7-mm-Planetary-HR----1-25--Okular--58---voll-multiverguetet.html (171x)

The 8mm... http://www.teleskop-express.de/shop/product_info.php/info/p158_TS-Optics-Optics-8-mm-Planetary-HR----1-25--Okular--58---voll-multiverguetet.html (150x)

These two eyepieces provide a very wide view at the low-to-moderate powers...

http://www.teleskop-express.de/shop/product_info.php/info/p4839_GSO-SuperView-15mm---1-25--WA-eyepiece---70--FoV.html (80x)

http://www.teleskop-express.de/shop/product_info.php/info/p2643_GSO-SuperView-20-mm---1-25--WA-eyepiece---70--FoV.html (60x)

An 8" Dobsonian comes with a 2" focusser.  You might want a single 2" eyepiece, for the lowest power possible with the telescope, and a wide, spacious view...

http://www.teleskop-express.de/shop/product_info.php/info/p808_GSO-Superview-42mm-2--Wide-Angle-Erfle-Eyepiece---60-Degrees.html (29x)

With that one, you would see the largest part of the sky, for the galaxy in Andromeda and the Pleiades in winter; and the rich, congested star-fields of the Milky Way in summer.  It would also help you find your way around the sky when star-hopping.

A 12mm... http://www.teleskop-express.de/shop/product_info.php/info/p4049_TS-Optics-Flatfield-Eyepiece-FF-12-mm-with-60--apparent-field-of-view.html (100x)

Do you already have the telescope, or are looking to get one?  Tell us about it.

[Jimtheslim]

I have only ever owned Meade plossls and these were fine and provided a noticeable improvement on the stock 10mm I got with the scope. Skywatcher are a well respected brand and as plossls go I am sure they would be ok.

The above post mentions baader classic ortho series. These really are brilliant. In the UK you can pick one up for about £35 used and at that kind of price a good ortho is definitely worth the money. you may want to upgrade from a plossl in the future, but a good ortho should stay with you a lot longer. I have nice wide field eyepieces in 8.8mm and 14mm, but my 10mm ortho still provides some of the best planetary viewing.

Always consider used eyepieces. These are almost always optically pristine and you're usually paying about 70% of the new retail price. I would also avoid buying a set of eyepieces. These look attractive in their cases and I guess some people will vouch for them but I've found it to be far better to build up my collection piece by piece.

[Mathyas]

Thanks everybody!

Be sure that i will go through all your suggestions. This forum is amazing! I am really delighted that you helped me

Have wonderful day and dark nights everyone!