Eyepieces for f4.7 dob

[Charic]

10 minutes ago, MSammon said:

Sorry just seen this. If that’s the case then  i might just try the 5 and the 8 as it’s the smaller ones I need to replace First. My 25 is more useable.

Correct the 25mm 'super' is useable. The 8mm BST Starguider will blow the supplied 10mm out the water, so to speak.
Your original post did ask for wide angle which is why were where we are at present, but all good fun, such is the learning process. 

To be honest, if the BST Starguider  (any focal length) works for you, and your happy with their comfort  and field of view, I've no doubt you would buy more than one, so now which one..............sorry, those choices are back again ?

[Ricochet]

13 minutes ago, MSammon said:

I think i need more experience to decide on exact sizes but I think an 8 and 18 would be good for now.  With 10” aperture in U.K. skies I’ve heard max useful magnification is aroubs X250?

The maximum magnification will vary on night to night, even hour to hour or minute to minute sometimes. Plus, it will depend on which planet you are looking at. This is why people tend to have quite a few similar focal lengths for planetary. A 7 or 8mm will probably be suitable almost every night. Shorter focal lengths will be useful less often. 

[Mike_S]

8mm Televue plossl ?

i never know until I press the order button! 

[Charic]

For comfort, field of view and affordability the 8mm Starguider was best for my needs, The 8mm Plössl will give you the same size  image, say your looking at Jupiter, with 10° less afov, and less eye relief, not good if your wearing glasses, I believe its 6mm. Its 16mm on the Starguider and something like 20mm of eye glass to peer through. Many would love to own the Brand of Tele View, but the Starguider for me leaves the Tele Vue Plössl standing. 

Buy both and compare. You may decide overall on the Tele Vue, that would't be a mistake, its your choice, but side-by-side, the Starguider has a lot going for it. I believe the only benefit the 8mm Plössl has is its  brand name, but performance wise,  only you  can decide. 

[Mike_S]

Okay Thats good to know. I wasnt sure it the Televue would have a sharper image or something. The BST’s say they’re suitable for F5 and above. What will I see if they’re unsuitable? Blurring around the edges or something? They do look great value. 

[Charic]

......at worst, your stars at the edge of your view will look like little comets? If I were to look carefully in my scope, using a wide enough eyepiece, I'd probably see something my self, but I like  and only track as best as I can using the central image in my viewfinder, which when I observe is simplicity itself. I care little for the extreme edge, because its not important to me. what I see is best right in the middle. 

The Tele Vue should give a sharp image across the field, but I don't recall seeing any difference to other Plössls I was testing at the time.
At 8mm, its probably less likely on a 60° ep that coma is evident at all, unless you know how/where to find it. Its when you go much wider in the field stakes that it becomes more evident.

[N3ptune]

One very good deal for low power observation widefields has to be the ES 68d 24mm in 1.25".  It's high quality, good price, well corrected, waterproof, easy to obtain, nice 68d FOV.

 

[John]

Nice piece here on telescope and eyepiece aberrations with illustrations of the different types. Exagerrated a bit to show the effect but you get the idea:

http://umich.edu/~lowbrows/reflections/2007/dscobel.27.html

The BST Explorers are pretty good for their cost. The I found the 8mm, 12mm and 18mm the best, the 25mm perhaps not quite as good. None are perfect in an F/5 scope but they present sharp and well defined images and enable the scope to do the best that it can, which is what it's all about. The next steps up in performance are relatively small and cost quite a bit to reach - consider that a Pentax XW costs 5x as much as a BST Explorer. Is the Pentax a better eyepiece ? - sure it is but the differences are quite subtle and no way could you say that the Pentax (or a Tele Vue Delos for that matter) performs 5x better (even if you could quantify eyepiece performance that way, which you can't).

My eyepiece sets are Tele Vue Ethos, Panoptic and Delos and Pentax XW's (it's taken me a long time to get here as well !) but I still have some BST Explorers which get regular use and I still enjoy using them. They are a significant step up from the "stock" eyepieces supplied with scopes. When I started out in this hobby 30 or so years back I'd have given my eye teeth for eyepieces of the quality of the BST Explorers

 

[Mike_S]

Are the BST Explorers better than the Baader Hyperions?

[Charic]

Although there is a variant called the Explorer, I'm certain John meant Starguider, though I could be wrong, John may still have some Explorers. There was a minor dispute over copyright?
That said an Explorer is one of the many variants of this eyepiece, all started I believe from the Astro-Tech Paradigm.

[John]

13 minutes ago, MSammon said:

Are the BST Explorers better than the Baader Hyperions?

In the central part of the field of view, there is no performance difference. The BST Explorers seem to be better corrected (ie: stars remain more star shaped !) in the outer parts of the field of view when used in fast scopes (ie: F/5 newtonians) than Hyperions. Hyperions show a wider apparent field of view (68 degrees vs 60 degrees), have a consistent eye relief of 20mm (the distance you put your eye behind the eye lens to see the full field), have better build quality and are quite a bit larger and heavier than the BST Explorers.

Edit: BST Starguiders are the same as BST Explorers - the eyepiece range was re-named a while back for some reason. No changes apart from that though. Sorry about the confusion !

Actually you will often see the same eyepieces for sale under a number of different brandings and with different names, often at very varying prices. It can get confusing to say the least !

 

 

[Mike_S]

I thought BST starguider was the make and Explorer ED 60 degrees the model. Theres some just come up on astro buy and sell 

[Saturnalia]

Lots of good advice. I have the same scope (F4.7 10") but we have no idea of your possible budget...? Anyway, here's my humble suggestion:

Keep your supplied 'super' 25mm and the 2X Barlow for now, get an 8mm Starguider and see how you like it and when you can afford it, get a 10mm Tele Vue Delos (to replace the supplied 10mm) - this will give you -

25mm - 48X mag

12.5mm - 96X mag (25mm with Barlow)

10mm - 120X mag

8mm - 150X mag

5mm - 240X mag (10mm with Barlow)

4mm - 300X mag (8mm with Barlow)

If you keep an eye open for them on the secondhand market, you should get both for around £250.

There are a couple of gaps around 70X and 200X mag but that can be dealt with once you have a better idea what you like and trying a Starguider and a Delos will give you a much better idea of the differences between a good budget eyepiece and a premium one. As stated earlier, buying secondhand gives you the added benefit that if you decide to change things later for whatever reason, you will probably lose very little money if you sell anything.

Later on you can decide what to do about your supplied 25mm EP and perhaps buy a premium Barlow to replace your supplied one.

 

 

 

 

[Charic]

Barsta make them........BST and 'Starguider' is the given name for the eyepiece collection that I'm referring too. ED is Extra Low Dispersion which helps reduce chromatic aberation, and the view  60° is the AFOV, apparent field of View.

[Mike_S]

Thanks. Budget is a funny one because I’m self employed. It’s more to do with what a I can justify spending money on over my house, wife and son instead. For some reason I’m feeling okay with up to around £150 a piece. I will keep looking second hand for Televues and Pentax. I think because of the 68 degree view I’m leaning towards the Baader Hyperions and they’re about the right price. I think like i did with my scope, I’ll see what a I can find second hand. Whether it be BST, Baader, Explore Scientific, Televue or Pentax. I am very grateful for learning a lot about this from you lot. I didn’t have a clue on eyepeices the other day other than how to calculate magnification. 

[DRT]

12 minutes ago, MSammon said:

I thought BST starguider was the make and Explorer ED 60 degrees the model. Theres some just come up on astro buy and sell 

Sometimes good things just fall out the sky  

[Saturnalia]

Have a read of these two threads:

 

 

[Charic]

11 minutes ago, Saturnalia said:

.........trying a Starguider and a Delos will give you a much better idea of the differences between a good budget eyepiece and a premium one.

For me the Starguider won!

The only difference I found was the expense and the field of view, yet as a reminder, my eyes on an f/6 scope. I would not expect the Delos to be six times better correcting an f/4.7

It would be interesting to here someones else's result, but don't expect the premium priced (6 times dearer) to be 6 times better.
For me only the field of view was apparent, the  look, shape, contrast everything in the images for me were no different. I had the 6, 8 and 10 Delos.

[Saturnalia]

I am only suggesting that MSammon should try it out for himself with his considerably faster F4.7 scope and buying secondhand negates any major financial penalty for trying it.

 

 

[John]

The challenge with buying Pentax XW's and Tele Vue Delos on the used market is getting them before anyone else does !!!!

Sometimes they sell within minutes of being advertised if the price is reasonable and the condition good (astronomers tend to look after their gear so the latter is usually the case).

The Explore Scientific 68 degree eyepieces are good alternatives as are the relatively new Baader Morpheus range.

So much choice in eyepieces today - almost too much !

[Charic]

3 minutes ago, Saturnalia said:

I am only suggesting that MSammon should try it out for himself with his considerably faster F4.7 scope..........

 

I'm not disputing your comment,  Just answering to the fact that I found no difference myself, although to be honest, I did expect a  big difference, just couldn't see or experience it.

And yes, f/4.7  is noteworthy, Ive not forgotten the fact, I did include the reference.

Never will there be a thread without  some form of interaction between users when someone asks, "which eyepiece" such is the nature on the subject of eyepieces. Its all done in good faith, helps the questioner form a better opinion, who knows!

Sorry if you thought there was any malice in/from my texts.

[Saturnalia]

Of course not Charic I was just clarifying my musings.

 

 

 

[Mike_S]

Found another interesting one that has been mentioned previously and reasonably priced. Explore Scientific 82 degrees? Slightly more than Baader Hyperions.

[Louis D]

12 minutes ago, MSammon said:

Found another interesting one that has been mentioned previously and reasonably priced. Explore Scientific 82 degrees? Slightly more than Baader Hyperions.

Or the TS UWANs (first introduced as the William Optics (WO) UWAN).  There's also a 28mm UWAN TS doesn't seem to stock.  They are considered to be at least as good as the ES-82 equivalents at a much more reasonable price.

[N3ptune]

Baader Hyperion I think should not be the benchmark with a F4.7, most people say they are not well corrected enough for that.

I once bought an eyepiece not suited for a fast Newtonian, the Q70 Orion 32mm with 70d AFOV.  I had to sell the Q70 after 11 months because there was 2 and perhaps 3 different aberrations off axis plus the coma which is not corrected by the eyepiece.

I was told here not to buy it and did it anyway..

I can manage a bit of coma but adding more aberrations to that, caused by the eyepiece, makes the observation unpleasant especially at low power. ?