StellaLyra 8" Dobsonian- best BST starguider eyepieces.

[theknopsy]

Hi, first time posting. 

 

I recently got the StellaLyra 8" Dobsonian (which comes with a 9mm Plossl and 30mm 2" EP) for Christmas and looking at upgrading from the stock Plossl.

I'm thinking of the 8mm and the 12mm which would give 150x and 100x respectively. But was then thinking would the 5mm a good choice instead of the 8mm or would it just not see that much use due to unstable atmosphere. Then regarding the 12mm would it be better to go for the 15/18mm to give a bit of a wider view (I have a 2x barlow so have the option to add some more power). 

 

Thanks for any info.

[mr_belowski]

I got the 18mm and was pretty unimpressed with it. I think each eyepiece in the range is different so they're not directly comparible but I wouldn't be a rush to get the 18 (although everyone's eyes are different so maybe it's a personal thing).

My 8inch aperture / 1200mm focal length dob works well down to about an 8mm. Anything shorter /  higher magnification tends to be a bit awkward - even when the seeing is OK the constant faff to keep stuff in view tends to limit how well you can view stuff because there's no time to allow the scope and your brain to 'settle'. The moon is the exception to that.

Considered a decent zoom? The baader Hyperion 8-24 was (last time i checked) on offer at FLO and is very highly regarded

[Ricochet]

When I bought my 8" dob the 8 and 12mm Starguiders were the first upgrade eyepieces that I bought. With a 2x barlow that is effectively 4, 6, 8, 12. Starting out you will probably think that more magnification is better but actually of the two the 12mm was my favourite because it gives a 2mm exit pupil in that scope and therefore is an ideal DSO eyepiece for any DSO that fits in the of view. For planetary the 8mm is a good choice and I used that more often than the barlowed 12mm due to the atmosphere so you would probably find a similar situation with the 5mm. When I bought a 7mm Celestron X-Cel LX I found I used that in preference to the starguider so a 7mm would be my preference for an all round planetary focal length with that telescope. 

The 18/25mm Starguiders need a scope with a focal ratio of at least f8. With your scope 5, 8 and 12 are the ones to get (or similarly the short X-Cel LXs). 

Edit: Given the current X-cel LX price, the OVL Nirvanas are possibly a better option if they are in budget and you do not leave the additional eye relief. 

Edited January 8, 2023 by Ricochet

[Kon]

I used to have the 8, 15 and 25mm BSTs. The 25 was not great at the edges with stars showing as seagulls. The 15 was excellent for DSOs, and the 25. The 8 excellent as well. I had the 2x starguider/bst barlow as well. In UK the nights that will allow you to use the 5 are quite limited.

[PeterStudz]

I have a Skywatcher 200p Dob, so a very similar telescope. I also have the 25, 12 & 5 mm Starguiders. As others have pointed out the 25mm isn’t the best and I plan to get something else to replace it soon, although it’s served its purpose. 

The 12mm has been the most useful out of the lot and I have no plans to upgrade this. Especially for DSO but also surprisingly good for planetary when used with a Barlow. I have the BST 2x Barlow and a cheap 3x Barlow to give 200x and 300x. Now, although conditions have got to be just right, on the few times this has happened the 12mm plus 3x Barlow has given me fab views of Saturn, very rarely Jupiter I admit and recently Mars. Obviously better than the 5mm which gives me 240x. Mars being a recent example, just 3 nights out of many, but 3 nights that I’m not going to forget. For some reason it’s the contrast/colour contrast with the 12mm plus Barlow that for me just works. 

Edited January 8, 2023 by PeterStudz

[Mr Spock]

Don't rule out high powers just because some say you can't use it. When conditions allow I use my 12" at x380 with great success. 

For your Dob, I'd recommend the 12mm and 8mm plus x2 Barlow. That will give you x100, x150, x200 and x300 - a really nice spread.

For wide field I'd suggest the 30mm StellaLyra UF. That would give x40 and 1.75°. Just right for getting the Pleiades in 😜

[Ratlet]

I'd give consideration to not getting the 8mm and Barlow (assuming it's the matched BST) and picking up the svbony 3-8mm zoom instead.  I've got the 8mm and Barlow for my 130pds (F5) and the svbony knocks spots off it.  It'll cost about the same as the 8mm and Barlow too.  You'll get plenty of use out of it at 8mm and can fine tune to focal length to your seeing and there's not much chance of you getting stumped out if the seeing great.

That is unless you need to wear glasses.

Edited January 8, 2023 by Ratlet
Clarified glasses.

[bosun21]

My first upgrades for my 8” Stella Lyra dobsonian was all the Starguider eyepieces apart from the 3.2mm. I was unimpressed with both the 18 & 25mm in my f6 dobsonian but they were decent in my 127 Maksutov. I found myself using the 15mm for DSO’s and the 8 & 12mm for the planets with a 2x barlow. The 12mm barlowed 2x gave 200x which was my planetary workhorse. I think I only had one occasion where the seeing and transparency allowed me to barlow the 8mm for 300x on Mars.

[cajen2]

I have the same scope as you.

The only BST I've ever owned is the 8mm, which worked very well over a wide range of targets but doesn't have quite enough beef for good planetary work. Barlowing it would give you 300x mag, which is very often too much for UK skies, but could be ok on the Moon with good seeing.

I graduated to wider-field EPs as they entail less nudging at high mags (Baader Morpheus and Pentax XWs). Over time, for planets, I've found the EP giving the best views in the widest variety of conditions is the Morph 6.5mm (185x mag). With excellent seeing, the Pentax 5mil (240x) works well, but not if conditions are only average.

If costs compel you to stick to BSTs, perhaps a barlowed 12mm would be your best bet for planets and it would also suit the brighter DSOs without the Barlow.

Edited January 9, 2023 by cajen2

[Guest]

You might consider 2 inch eyepieces and a 2 inch 2x barlow.  I know FLO has a line of eyepieces that are 82 degrees.  The 20mm is a gem, in a 2x barlow that would get you the equal of a 10mm and you will will have all the pluses that a 2 inch eyepiece gives you.  Just something to consider. 

 

[theknopsy]

Hi all, 

Thanks a lot for all the advice, it has been really useful in gauging the strenghts and weaknesses of a range of EPs. I decided to go for the 8mm and 12mm BST coupled with the 2x Barlow that I already have I feel will give a good range of magnifications as @Mr Spock said. 

Thanks again to everyone who replied!

[Joef]

I’ve got the 12mm and 5mm BST E/p, I really like the 12mm, but just can’t get on with the 5mm, it’s probably just me and my eyes. 

[great_bear]

On 08/01/2023 at 15:19, mr_belowski said:

I got the 18mm and was pretty unimpressed with it.

When I asked about the Starguiders on CloudyNights, it was mentioned that the 18mm appears to be the weak point of both the Starguider and Celestron X-Cel LX lines, with neither being a clear winner.

I have a 12mm and 5mm Starguiders. Both are superb, although the 5mm needed an extra baffle fitting to improve lunar performance.

I now have a 3.2mm on the way. 

The Starguiders are for my (wife's) Sky-Watcher 130P Explorer, in which they work very well. In the Dob I use Tele Vue Delos instead.

Edited January 23, 2023 by great_bear

[Louis D]

The 18mm Meade HD-60 is similarly the weakest link in that line as well.

The problem is that all of these step-up 18mm eyepieces are positive-only designs with no negative Smyth lens group to improve correction in faster scopes.  The 18mm APM UFF and its brand-mates would probably be a good bet at that focal length since it is a negative-positive design.  Yes, it is considerably more expensive.

[cajen2]

Just to throw another 18 mil EP into the mix, the StellaLyra 68° LER/WA is a good, solid one with no obvious aberrations in my scopes. The new SL UFF is the same as the APM but even cheaper.

[Louis D]

I just recalled another 18mm step-up eyepiece that had poor performance relative to its stablemates.  It was the 18mm 55° LER made by Long Perng and sold under many different names.  Again, it lacked a Smyth lens group and had really poor edge correction even in modest f-ratio scopes.  The rest of the line all had Smyth lenses and were well regarded.

[great_bear]

2 hours ago, Louis D said:

The 18mm Meade HD-60 is similarly the weakest link in that line as well.

The problem is that all of these step-up 18mm eyepieces are positive-only designs with no negative Smyth lens group to improve correction in faster scopes.  The 18mm APM UFF and its brand-mates would probably be a good bet at that focal length since it is a negative-positive design.  Yes, it is considerably more expensive.

FLO do a StellaLyra version at £109

What's the concensus on how the StellaLyra Kitakaru's perform at these tricky 18mm and 25mm focal lengths with F5/F6 scopes Louis - do you know?

Edited January 23, 2023 by great_bear

[Mr Spock]

If you are looking at eyepieces under £100 then for me the best choice is the Nirvana https://www.firstlightoptics.com/ovl-eyepieces/nirvana-es-uwa-82-ultrawide-eyepieces.html They are a big step up from the BST but not really a lot more money.

I have all of them. The 13mm and 7mm would give x92 and x171 - very useful; or you could choose the 13mm and 10mm, plus x2 Barlow giving x92, x120, x185, x240 - I like the sound of that. As well as the obvious advantage of 82°, they are sharp and comfortable to use.

[IB20]

The 15mm BST is a brilliant EP and works incredibly well with an 8” Dob. The 5mm is also extremely good but would probably be limited to lunar viewing and Mars. I got a 10mm Baader Classic Ortho and that beat the 12mm and 8mm BSTs hands down. It also barlow really well too.

Edited January 23, 2023 by IB20

[Don Pensack]

4 hours ago, cajen2 said:

Just to throw another 18 mil EP into the mix, the StellaLyra 68° LER/WA is a good, solid one with no obvious aberrations in my scopes. The new SL UFF is the same as the APM but even cheaper.

Yeah, by £50.

[Don Pensack]

5 hours ago, Louis D said:

The 18mm Meade HD-60 is similarly the weakest link in that line as well.

The problem is that all of these step-up 18mm eyepieces are positive-only designs with no negative Smyth lens group to improve correction in faster scopes.  The 18mm APM UFF and its brand-mates would probably be a good bet at that focal length since it is a negative-positive design.  Yes, it is considerably more expensive.

That 18mm UFF is only £109 from FLO.

That is very inexpensive for such a well-corrected 65° eyepiece.

[Louis D]

3 hours ago, great_bear said:

What's the concensus on how the StellaLyra Kitakaru's perform at these tricky 18mm and 25mm focal lengths with F5/F6 scopes Louis - do you know?

Nothing more than what I've read on CN.  Probably best in slower f-ratio scopes based on that.

[Louis D]

5 minutes ago, Don Pensack said:

That 18mm UFF is only £109 from FLO.

That is very inexpensive for such a well-corrected 65° eyepiece.

However, once VAT is removed, shipping to US added, and GBP to USD converted, it comes out to within $10 of your 18mm APM UFF price.  The GBP is well off of its September 2022 lows.

[Louis D]

3 hours ago, Mr Spock said:

If you are looking at eyepieces under £100 then for me the best choice is the Nirvana https://www.firstlightoptics.com/ovl-eyepieces/nirvana-es-uwa-82-ultrawide-eyepieces.html They are a big step up from the BST but not really a lot more money.

I have all of them. The 13mm and 7mm would give x92 and x171 - very useful; or you could choose the 13mm and 10mm, plus x2 Barlow giving x92, x120, x185, x240 - I like the sound of that. As well as the obvious advantage of 82°, they are sharp and comfortable to use.

All well and good as long as you don't need moderately long eye relief.

[great_bear]

14 minutes ago, Don Pensack said:

That 18mm UFF is only £109 from FLO.

That is very inexpensive for such a well-corrected 65° eyepiece.

Is a 24mm UFF likely to be better corrected at F5 than a 24mm SWA (Meade 5k)?

The 10mm UFF didn’t work out well for me at F5 and I sent it back.