Need assistance with Eyepiece Upgrade

[Located]

9 minutes ago, Pixies said:

I've heard people slag off the 10mm basic Skywatcher EPs, and others say they are OK. I wonder if this is a matter of poor quality control at this price-point and their quality is variable.

I have a couple somewhere gathering dust (from secondhand scope purchases). I'll need to compare them.

Yeah, I'm unable to compare any but I'm definitely going to check their differences once it arrives. The basic EP that I currently use (until the BST ones come) don't honestly look too bad, personally I wouldn't slag them off but will depend on their differences which I hope to see once the BST's arrive. I used the basics yesterday as it was surprisingly a little clear and got a nice view on Jupiter, though I've never used any other EP than the basic so I may be in for a slight shock I'm not sure haha.

Edited August 10, 2021 by Located

[John]

9 minutes ago, Pixies said:

I've heard people slag off the 10mm basic Skywatcher EPs, and others say they are OK. I wonder if this is a matter of poor quality control at this price-point and their quality is variable.

I have a couple somewhere gathering dust (from secondhand scope purchases). I'll need to compare them.

That would be interesting.

I have the 20mm and 10mm stock eyepieces branded Celestron knocking around somewhere.

It would be interesting to compare the 10mm with, say, my Pentax XW 10mm and see just what the "gap" between them is - I wonder if it is £230 quids worth (assuming that the 10mm stockie is worth around £20 new)

[jetstream]

8 minutes ago, John said:

my Pentax XW 10mm

theres a reason why you own this eyepiece

[Pixies]

Mind you. I've used the 'starter' 25mm Celestron EP - the plastic 'terrestrial' viewing one, and the only place that belongs ceratinly isn't a telescope!

[jetstream]

On 09/08/2021 at 14:20, Mr niall said:

But now they come with a “Super” but it isn’t a plossl, it’s a MA.

I checked last night and youre right it doesnt say plossl on the eyepiece. It still shows me the HH very well, among other targets.

[Pixies]

I thought I'd do a little subjective testing with a pair of Skywatcher starter EPs that I had in the box of unused stuff. I had the little ST80 out to look at the recently brightening nova, RS Ophiuchi. I thought I'd compare the view of the double-star Albireo with some different EPs. Now, this refractor is short and fast, so a little taxing on EPs, also I don't use my specs when observing and I'm a little astigmatic, so the 25mm EP views will suffer a little from  my own shortcomings. The sky was still a little light when I started but I completed the comparisons within 30 minutes and went back over the different EPs, so there shouldn't be much difference in sky quality.

25mm:
=====

25mm Skywatcher.
Very adequate view but with strange effects at the field stop. The sky was still a little light when tested, but approaching the field stop, it started to dim and to fade to black. But beyond that, some reflectivity showed as a bright ring outside the stop. Made a very strange border to the view!

25mm Bresser super plossl.
Comes as the single starter eyepiece with Bresser scopes- I think this is a GSO EP? Very lightweight compared to the Skywatcher, but a similar quality view but without the odd field-stop.

Both show astigmatism off-axis in the F/5 scope and my eyes aren't the best with this 5mm exit pupil, either. But the view of Albireo starts to become distorted further from the centre of view in the Bresser than the Skywatcher. 

 

10mm:
=====

10mm Skywatcher. The (in)famous EP in question above.
Absolutely beautiful view of the orange/blue double star in the centre of view. Clear and sharp and fantastic colours. But... (noting again this is an F/5) astigmatic distortion starts showing at only a third of the way out from axis centre to field-stop. From around two thirds out, the distortion makes the view worthless.

Now, I don't have any other 10mm eyepieces, but for comparison:

12mm BST Starguider. Sharp and clean at the centre, perhaps slightly not as colourful as the 10mm Skywatcher, though. Much wider FOV (60 deg). Pretty much astigmatism-free but field-curvature showing in this short refractor from two-thirds out from the central axis. Re-focussing cures this and the double-star can remain distortion-free to the field-stop with a little focus adjustment.

8mm University Optics Ortho. Similar view to the 10mm Skywatcher on-axis, but a little dimmer with the higher magnification. Astigmatism starting to show from 50% out but not to the same extent as the 10mm Skywatcher. Useable view to the (admittedly narrower) field stop

8mm Vixen LVW. Yes - chalk and cheese, I know. 65 deg FOV. Sharp, bright and colourful view. No obvious astigmatism or field-curvature to my eyes. Albireo sharp all the way to the very clean field stop.

What does this prove? You get what you pay for, generally. But as @John mentions, it's probably a law of diminishing returns. The Vixen LVW was £200 new, although not produced now. Is it worth £180 more than the 10mm Skywatcher? I paid £80 for it. Is it worth £60 more than the 10mm Skywatcher? When I first started, would I even have noticed much of a difference in the view between them, apart from the obvious FOV differences? That and the size and weight!

[John]

Poor conditions here limited my comparisons to a "quick and dirty" look at Epsilon Lyrae, Pi Aquillae and Messier 57, the Ring Nebula. The scope was my ED120mm F/7.5 refractor.

With the Celestron branded K10mm "stock" eyepiece (not marked "super" at all ) the views in the central 50% of the field of view were sharp with this scope but splitting these close star pairs became harder as the target neared the edge of the field of view and in the last 10% or so the splits were practically impossible to make. I was using the Baader 2.25x barlow lens with the K10mm to make it a 4.4mm for Pi Aquillae.

The comparison eyepieces were, really quite unfairly, the Pentax XW 10mm and the Tele Vue Nagler 2-4mm zoom at the 4mm setting. I also used the Hyperflex (clone) 7.2mm - 21.5mm zoom eyepiece at the 10mm setting as another, less pricey, option.

More than the sharpness fall off towards the field edge, the most notable difference between the more expensive eyepieces and the stock K10mm was the brightness of the views. Although a simple 3-element design, the K10 views of both the star fields and the Ring Nebula just looked dimmer all over. When the better (and much more expensive) eyepieces went in, the difference was noticeable with the fainter stars in the view popping out more obviously and the contrast variations across the surface of the nebula being quite a lot easier to see, despite the rather poor observing conditions.

To be fair, the K10mm stock eyepiece was quite usable and the view in the central portion of the field of view was by no means bad. It was just a dimmer view and lost sharpness towards the edge of the field.

 

 

[Louis D]

So much for the oft trotted out theory that eyepieces with fewer elements always produces a brighter, contrastier image than that from an eyepiece with a large number of elements.  Perhaps it's true if the level of polish, coatings, and glass purity are similar between the two eyepieces, but so will be the prices (e.g., Tak TOA vs TV Delos).

[bingevader]

Comparing a budget EP with fewer elements to a high end EP with more isn't likely to work.

But how about from the same firm?

TV plossl v TV delos?

I don't know if that is a good comparison, as I have no idea how many elements are in a delos.

I'm sure the big boys with all the toys could do a sensible comparison,

[John]

41 minutes ago, bingevader said:

Comparing a budget EP with fewer elements to a high end EP with more isn't likely to work.

 

Well it does "work" but the result is not really a surprise.

It was just a bit of fun really - is the stock 10mm really that bad ? and what are the actual, tangible, differences between eyepieces with a 10x difference in price tag ?.

I'm sure the more predictable comparisons have been done somewhere over the past few years. And then debated for another couple !

 

 

[bingevader]

You are right John, 'work' probably wasn't the best word to use.

My stock 10mm isn't really that bad.

I'm happy to use it in school (with some other budget EPs) without feeling the children are getting a raw deal.

Anyway, I am sure the OP will enjoy the 8mm BST at least!

[Mr niall]

I’ve tried for years to find eyepieces that I really like - although being a bit of a funny OCD kind of person I kind of like all my eyepieces to be of the same brand!

I’ve tried BST Starguiders, Vixen NPL, Baader Hyperion… there are others.

In the end I bought a full set of “Series 500” plossls (all 9 of them) from China for £85. £ for £ none of these little guys compares with the mid range ones I’ve used before (The Vixen NPL 30mm and BST 15mm are particularly good). 
 

But I’ve done enough observing to know I’m not “missing out” on anything and my eyepieces definitely aren’t holding me back. They’re solid, sharp in the middle of The FOV, I’ve got every focal length I could ever need and they’re compact and I’m not terrified of breaking them. I can’t see myself replacing them ever.

Whatt I’m saying is sometimes you have to try out better eyepieces to know what you want. But it’s so subjective, half a million people could have told me when I started out “the stock EPs are fine just stick with them” and I would have ignored them all! So much of it is down to weird things like aesthetics and personal attachment.

But the amount you spend doesn’t necessarily dictate the potential pleasure you will derive. 

 

[Pixies]

5 minutes ago, Mr niall said:

I’ve tried for years to find eyepieces that I really like - although being a bit of a funny OCD kind of person I kind of like all my eyepieces to be of the same brand!

I’ve tried BST Starguiders, Vixen NPL, Baader Hyperion… there are others.

In the end I bought a full set of “Series 500” plossls (all 9 of them) from China for £85. £ for £ none of these little guys compares with the mid range ones I’ve used before (The Vixen NPL 30mm and BST 15mm are particularly good). 
 

But I’ve done enough observing to know I’m not “missing out” on anything and my eyepieces definitely aren’t holding me back. They’re solid, sharp in the middle of The FOV, I’ve got every focal length I could ever need and they’re compact and I’m not terrified of breaking them. I can’t see myself replacing them ever.

Whatt I’m saying is sometimes you have to try out better eyepieces to know what you want. But it’s so subjective, half a million people could have told me when I started out “the stock EPs are fine just stick with them” and I would have ignored them all! So much of it is down to weird things like aesthetics and personal attachment.

But the amount you spend doesn’t necessarily dictate the potential pleasure you will derive. 

 

True.

I'm not sold on wide-field views. I have an 18mm version of the often recommended Nirvana 82deg EPs , but just don't get on with it. It's like  sitting too close to the cinema screen!

[Louis D]

1 hour ago, Mr niall said:

In the end I bought a full set of “Series 500” plossls (all 9 of them) from China for £85.

I wonder if they're from the same line reviewed on CN in 2006.

That's a great price.  The best I could find for them was $186 on ebay.

[Louis D]

1 hour ago, Pixies said:

It's like  sitting too close to the cinema screen!

Do you also prefer standing well back from a window when looking outside? 😉😁

Edited August 12, 2021 by Louis D

[John]

I've been though the "must own full set / all the same brand" thing but eventually realised that I was not doing myself any favours with regards to the overall effectiveness of such collections so now I've gone back to cherry picking from ranges and (generally) not owning focal lengths that don't do something useful with my scopes / sky conditions / observing interests.

I still can't shake off the draw of wide, expansive fields of view but that may well be because all my scopes are used on undriven / alt-azimuth mounts. In saying that my current eyepiece sets cover from around 40 degrees to 110 degrees so I have plenty of variation available 

 

 

[Mr niall]

1 hour ago, Louis D said:

I wonder if they're from the same line reviewed on CN in 2006.

That's a great price.  The best I could find for them was $186 on ebay.

Yeah similar I think.

This was them

https://www.aliexpress.com/item/32962028327.html

like you say, the don’t seem to be available anymore. I only bought them 12 months ago too!

[bingevader]

I suppose I nearly have a full set of the Meade plossls now, but the rest are very much not of the same brand!

I too like the wider field of view, but my cherry picking has been done very much on price rather than performance.

Thankfully I haven't been disappointed, but that's probably the joy of not having anything 'better' to compare them too.

[Louis D]

7 hours ago, Pixies said:

I'm not sold on wide-field views. I have an 18mm version of the often recommended Nirvana 82deg EPs , but just don't get on with it. It's like  sitting too close to the cinema screen!

Seriously, though, some of that may be due to lack of eye relief or having a difficult to hold exit pupil, either of which can make it tiresome to use for extended periods of time.

If you've got the bucks, try a 17mm ES-92 sometime instead.  It has 17mm of usable eye relief and an easy to hold exit pupil.  The view is just all there, all at once.  You don't have push in hard or tip your head to see the edges.  Just look straight ahead while hovering above the eyepiece, and it appears to be full of stars well out into your peripheral vision.

[0rcrest]

well i just dived straight in and bought a 3.5 starguider ed for my heritage 130p -got it for £30 on ebay its massive inc case came today hoping for clear  skies and Jupiter )

[John]

11 minutes ago, 0rcrest said:

well i just dived straight in and bought a 3.5 starguider ed for my heritage 130p -got it for £30 on ebay its massive inc case came today hoping for clear  skies and Jupiter )

The 3.2mm ?

That will give you 203x - useful when the conditions are decent

Good for Saturn and the Moon. Might be useful for Jupiter if the conditions are particularly good. Jupiter usually benefits from slightly lower magnifications but see how it goes

[0rcrest]

i know i hope it's not to high ,i got a good price and may sell it if i need to but the moon i'm hoping will give me a natural good mag ,and it suits my f5  

[Louis D]

The 3.2mm should be good for resolving globular clusters as well.  It's the only Paradigm (Starguider BST) I don't have, so I can't verify how good or bad it performs.  The 5mm performs quite well, though.  Not as good as my vintage 5.2mm Pentax XL, but still quite good.

[Zermelo]

12 hours ago, 0rcrest said:

well i just dived straight in and bought a 3.5 starguider ed for my heritage 130p -got it for £30 on ebay its massive inc case came today hoping for clear  skies and Jupiter )

Congratulations, that's a decent price if it came from a good home. I've not used the 3.2mm but it is physically the largest in the Starguider range, and a bit of a surprise compared with the stock eyepieces. Now let's hope for some still nights where you can put it through its paces.

[Located]

Something's arrived in the mail today 👀

Glad to have my hands on them, now must hope for some clear weather in the coming days. Thanks to everyone once again for assisting me with what EP's to buy etc, appreciate it very much!

Clear Skies!