What eyepieces time buy for first telescope?

[AlanP_]

Hi all,

i bought my first telescope today second hand. It’s the Celestron astromaster 90EQ and I got an excellent deal on it. My budget was around 2-300 and I got this for 60 used in my area. I’m wondering if I should spend some extra on some eyepieces, would it be worth it? I was researching in eyepieces but tbh I’m still a bit confused on if I’d benefit from them.

Can anyone advice me on this?

[Guest]

FLO has restocked it's supply of BST StarGuider eyepieces. I use them with my Sky-Watcher Skyliner 200P Dobsonian. 

There's a link to FLO at the very top of this page. 

[AlanP_]

21 minutes ago, merlin100 said:

FLO has restocked it's supply of BST StarGuider eyepieces. I use them with my Sky-Watcher Skyliner 200P Dobsonian. 

There's a link to FLO at the very top of this page. 

What one would I get the most use out of for my telescope?

[Guest]

9 minutes ago, AlanP_ said:

What one would I get the most use out of for my telescope?

I'm not an expert, far from it. I'd suggest perhaps the BST StarGuider 18mm, 15mm or 12mm. I think the 8mm may work for you, but that maybe at the limit? 🤔

I'm a big fan of this range of eyepieces, based on the recommendations by many people on this forum! 

I'm sure someone with far more experience will chip in with some good pointers...

[Ruud]

If you have the original eyepieces they won't be very good. The 60° Starguiders https://www.firstlightoptics.com/bst-starguider-eyepieces.html are significantly better and a good bargain.

Your telescope is f/11. You will get usable magnifications with eyepieces from 5.5mm focal length and up (11 divided by 2). Below 5.5mm focal length you will get higher magnifications but things will not look pretty. The image will become increasingly dark and blurry as the magnification goes up. 

One option is an 8mm and an 25 mm BST. (125x and 40x)

Another option is a 15mm and a 25mm BST together with a 2x Barlow. This gives you effective focal lengths of 7.5, 12.5, 15 and 25mm. (133x, 80x, 67x and 40x)

A third option is the 50° GSO 32mm Plössl, a 12mm BST Starguider and a 2x Barlow. Effective focal lengths would be 6, 12 16 and 32mm. (167x, 83x, 63x and 31x)

I really like the TeleVue 2x Barlow, but the BST Starguider Barlow might be almost as good at fraction of the cost - I don't know.

 

 

 

 

Edited July 18, 2020 by Ruud

[AlanP_]

1 minute ago, Ruud said:

If you have the original eyepieces they won't be very good. The 60° Starguiders https://www.firstlightoptics.com/bst-starguider-eyepieces.html are significantly better and a good bargain.

Your telescope is f/11. You will get usable magnifications with eyepieces from 5.5mm focal length and up (11 divided by 2). Below 5.5mm focal length you will get higher magnifications but things will not look pretty. The image will look increasingly dark and blurry as the magnification goes up. 

One option is an 8mm and an 25 mm BST. (125x and 40x)

Another option is a 15mm and a 25mm BST together with a 2x Barlow. That gives you effective focal lengths of 7.5, 12.5, 15 and 25mm. (133x, 80x, 67x and 40x)

A third option is the 50° GSO 32mm Plössl, a 12mm BST Starguider and a 2x Barlow. Effective focal lengths would be 6, 12 16 and 32mm. (167x, 83x, 63x and 31x)

I really like the TeleVue 2x Barlow, but the BST Starguider Barlow might be almost as good at fraction of the cost - I don't know.

 

 

 

 

This is exactly what I was looking for, thats super helpful thanks so much! I think i'll go with your second or third option, ill do a bit more research and see.

Just out of curiosity, what should I be able to see with this telescope?

[AlanP_]

6 minutes ago, merlin100 said:

I'm not an expert, far from it. I'd suggest perhaps the BST StarGuider 18mm, 15mm or 12mm. I think the 8mm may work for you, but that maybe at the limit? 🤔

I'm a big fan of this range of eyepieces, based on the recommendations by many people on this forum! 

I'm sure someone with far more experience will chip in with some good pointers...

Similar to what Ruud said too, must be a good shout so! Thanks so much!

[toshapetriji]

There is a perfect thread for eye pieces.

 

 

[Guest]

Another option could be a good set of Plossl eyepieces.  You can get them from FLO for between £20-£30 each, depending on the manufacturer and model.  Again, there maybe someone better qualified to offer an opinion. 

[Cosmic Geoff]

Plossls should be good enough for a f11 telescope, particularly for the longer focal length eyepieces.

[AlanP_]

6 hours ago, Ruud said:

If you have the original eyepieces they won't be very good. The 60° Starguiders https://www.firstlightoptics.com/bst-starguider-eyepieces.html are significantly better and a good bargain.

Your telescope is f/11. You will get usable magnifications with eyepieces from 5.5mm focal length and up (11 divided by 2). Below 5.5mm focal length you will get higher magnifications but things will not look pretty. The image will become increasingly dark and blurry as the magnification goes up. 

One option is an 8mm and an 25 mm BST. (125x and 40x)

Another option is a 15mm and a 25mm BST together with a 2x Barlow. This gives you effective focal lengths of 7.5, 12.5, 15 and 25mm. (133x, 80x, 67x and 40x)

A third option is the 50° GSO 32mm Plössl, a 12mm BST Starguider and a 2x Barlow. Effective focal lengths would be 6, 12 16 and 32mm. (167x, 83x, 63x and 31x)

I really like the TeleVue 2x Barlow, but the BST Starguider Barlow might be almost as good at fraction of the cost - I don't know.

 

 

 

 

https://www.firstlightoptics.com/skywatcher-eyepieces/skywatcher-sp-plossl-eyepieces.html

What about these ones? Theyre have the cost of the BST ones, but whats the differnece?

[AlanP_]

Also, whats the difference bwteen the Vixen SLV and Vixen NPL eyepieces? Would it ber worth going for those?

[John]

NPL's are plossls. SLV's are a more sophisticated multi element design that uses lanthanum glass.

In your scope standard plossls like the Skywatcher or Vixen NPL's would work well.

The BST Starguiders give you a larger field of view (60 degrees vs 50 degrees) than plossls and more eye relief (distance your eye needs to be from the top of the eyepiece).

If you want to keep the cost down plossls will do fine and you might be able to get 3/4 of them which will give you more options to exploit the scopes capabilities.

These are all a step up from the stock eyepieces supplied with scopes.

 

[AlanP_]

6 minutes ago, John said:

NPL's are plossls. SLV's are a more sophisticated multi element design that uses lanthanum glass.

In your scope standard plossls like the Skywatcher or Vixen NPL's would work well.

The BST Starguiders give you a larger field of view (60 degrees vs 50 degrees) than plossls and more eye relief (distance your eye needs to be from the top of the eyepiece).

If you want to keep the cost down plossls will do fine and you might be able to get 3/4 of them which will give you more options to exploit the scopes capabilities.

These are all a step up from the stock eyepieces supplied with scopes.

 

Do you reckon it would be worthwhile to get one or two SLV eyepieces? Would it be worth it over some plossls?

[AlanP_]

Or maybe get one SLV eyepiece and 2 other plossls?

[John]

Vixen SLV eyepieces are of excellent quality but I'm not sure you would notice much, if any, difference in your F/11 90mm refractor.

When I tested them for the forum I was using faster scopes (more challenging on eyepieces):

 

[AlanP_]

2 hours ago, John said:

Vixen SLV eyepieces are of excellent quality but I'm not sure you would notice much, if any, difference in your F/11 90mm refractor.

When I tested them for the forum I was using faster scopes (more challenging on eyepieces):

 

Ah ok makes sense. I probably will upgrade down the line though is the only thing. So would it make sense to go with the SLV now?

Or perhaps go with a 10 or 12mm SLV now, and a 30mm BST now with a 2x barlow? I really dont know, im very indecisive!

What would you for if you were in my position?