BST starglider EP

[Beardy30]

Hi I’m looking to add to/improve in the 10mm and 25mm EP that came with my startravel 102 - any recommendations? 
the 5mm has been suggested but I’m not sure if this would be a good option? 

[cajen2]

As usual, the answer lies in how much you're looking to spend....or you'll get people recommending TV Ethos at £6-800 a pop!

BSTs are certainly excellent value for money but spending more gets you better views....😈

Edited February 13 by cajen2

[Beardy30]

Thanks , Sorry I wasn’t specific- I’m already set for on the BST range and my question was directed just a opinion on the mm size I should opt for to upgrade my two stock EPs I got with the 102 - I’m not looking at other brands - the 5mm BST was mentioned but I’m unsure if it’s the right one - thanks 

[cajen2]

Ah, ok, got you.

I'd go initially for something like the 5mm for planets, the Moon, double stars, etc. Then perhaps a mid-range one, say a 15mil for medium- sized targets. I would urge you, though to consider a low mag, widefield EP: something like a StellaLyra 30mm UFF. I realise this is a lot more money but it's dual function: for stuff like the Pleiades and Andromeda Galaxy, plus it acts as a great finder EP - makes finding a target and star hopping much easier. Cheaper 30-40mm EPs are available but have much narrower fields of view, so not much improvement on your 25.

[cajen2]

Oh, I've just thought about it: the 30mm SL is a 2" and I don't suppose you want the expense and trouble of getting a 2" diagonal. 

My other recommendation would be a Vixen NPL 30 or 40 mm. 1.25" but a narrower FOV than the SL. I use a 30mm when I can't be bothered to change my diagonal and it's excellent for its price.

Edited February 14 by cajen2

[SCANS]

My family and I have been quite happy with our StarGuiders and our StarTravel 102. They've certainly lived up to the hype for us. You might want to check the prices at FLO. We got a good discount from them by purchasing several at once instead of one at a time. In terms of which sizes to start with, the 5mm seems like a good recommendation. That's about the maximum magnification (100x) that we use with that scope. You might also consider the 8mm and/or 12mm because we found the stock 10mm a bit tiring to use. The StarGuiders are just much more comfortable with more eye relief, wider FoV, easier eye placement, and the twist up eyecup. The stock 25mm isn't too bad, so upgrading for low power probably wouldn't be a priority yet and you might find that the jump from the stock 25mm to 12mm and then 5mm will suffice. Although I do use the 8mm more than the 12mm in this scope because I find that the 63x magnification with 1.6mm exit pupil is more pleasant. Which ever you choose, I'm pretty sure you won't be disappointed.

[SCANS]

1 hour ago, cajen2 said:

Oh, I've just thought about it: the 30mm SL is a 2" and I don't suppose you want the expense and trouble of getting a 2" diagonal. 

My other recommendation would be a Vixen NPL 30 or 40 mm. 1.25" but a narrower FOV than the SL. I use a 30mm when I can't be bothered to change my diagonal and it's excellent for its price.

Not sure if I'd go beyond 25mm for low power with this scope. It's a short tube (f/5) so 25mm yields 20x with an exit pupil of 5.1mm and a 2.5° FoV with the stock 25, or 3.0° with a StarGuider. I also have an inexpensive 30mm that I use as a finder once in a while. It isn't near as good as either the SL or Vixen, but while it's cool to see so much sky at once, the magnification is so low and the exit pupil is so large that I don't find as enjoyable in this scope.

[Louis D]

I don't know if you read my write up on the BST Starguider/Paradigm line, but here it is if you missed it:

It might be worth a read if you want to know how the various focal lengths compare (minus the 3.2mm).

[Mr Spock]

There's a review of the 5mm here https://astro-talks.ru/forum/viewtopic.php?f=32&t=1557#p20906

[Beardy30]

12 hours ago, cajen2 said:

Ah, ok, got you.

I'd go initially for something like the 5mm for planets, the Moon, double stars, etc. Then perhaps a mid-range one, say a 15mil for medium- sized targets. I would urge you, though to consider a low mag, widefield EP: something like a StellaLyra 30mm UFF. I realise this is a lot more money but it's dual function: for stuff like the Pleiades and Andromeda Galaxy, plus it acts as a great finder EP - makes finding a target and star hopping much easier. Cheaper 30-40mm EPs are available but have much narrower fields of view, so not much improvement on your 25.

Thanks - too expensive though for me I’ll stick to the BSTs

[Beardy30]

9 hours ago, Louis D said:

I don't know if you read my write up on the BST Starguider/Paradigm line, but here it is if you missed it:

It might be worth a read if you want to know how the various focal lengths compare (minus the 3.2mm).

I’d like to know what’s best for my particular scope but I will read cheers 

[Beardy30]

1 hour ago, Mr Spock said:

There's a review of the 5mm here https://astro-talks.ru/forum/viewtopic.php?f=32&t=1557#p20906

Is that in Vulcan 😂😂

[Beardy30]

11 hours ago, SCANS said:

My family and I have been quite happy with our StarGuiders and our StarTravel 102. They've certainly lived up to the hype for us. You might want to check the prices at FLO. We got a good discount from them by purchasing several at once instead of one at a time. In terms of which sizes to start with, the 5mm seems like a good recommendation. That's about the maximum magnification (100x) that we use with that scope. You might also consider the 8mm and/or 12mm because we found the stock 10mm a bit tiring to use. The StarGuiders are just much more comfortable with more eye relief, wider FoV, easier eye placement, and the twist up eyecup. The stock 25mm isn't too bad, so upgrading for low power probably wouldn't be a priority yet and you might find that the jump from the stock 25mm to 12mm and then 5mm will suffice. Although I do use the 8mm more than the 12mm in this scope because I find that the 63x magnification with 1.6mm exit pupil is more pleasant. Which ever you choose, I'm pretty sure you won't be disappointed.

Fabulous advice thank u 😊 

[Louis D]

Just now, Beardy30 said:

I’d like to know what’s best for my particular scope but I will read cheers 

What's often most important is what's best for your eyes and facial shape.  For instance, I have massive astigmatism in my observing eye, so I need to wear eyeglasses at the eyepiece to get the best image even at high powers and small exit pupils.  Thus, long eye relief is important to me.  For me, only the 25mm BST Starguider has sufficient eye relief to use comfortably while wearing eyeglasses.

I also have deep set eyes, so eyepieces with a broad, flat top don't work well for me.  The original 30mm ES-82 with mushroom top has such a broad top that it requires me to tilt my head to the side and swivel my eye in the opposite direction to get close enough to use it properly.  The BST Starguiders are all quite narrow across the top, so no such issues with them.

The 5mm BST Starguider is a good eyepiece if you don't need to wear eyeglasses at the eyepiece.  It should also provide a nice step up in image quality and magnification from your existing 10mm.

[Louis D]

Did your scope come with a correct image diagonal?  If so, I recommend replacing it ASAP with a proper 90 degree mirror or prism diagonal.  It will provide a larger clear aperture for widest field viewing without vignetting and provide sharper images without bright star spikes as occurs with correct image diagonals.

[inedible_hulk]

I’d suggest reading this and doing the sums if you haven’t already. It’s served many a beginner, including myself, well. In my opinion, the BSTs are a good step up from the stock eyepieces.