Help me choose a 12mm eyepiece please

[mikey2000]

I'm about to receive a 150PDS on EQ3Pro Synscan.  Once my old scope is sold, I'll be left with a 6mm, 40mm in 1.25" and a panaview 32mm in 2".  All very nice.  I'm quite happy with my 6, 40 and I'm sure I'll love the 32mm.  I also have a 2x barlow in 1.25"

 

But there's a big gap in magnication here. 

 

I see lots of sets include a 12mm 'in the middle' so I think, "why not go with the majority view and plug my gap with a 12mm"

 

I hope that is a sensible choice.  If so, can anyone recommend a reasonable 12mm.   I wear glasses and prefer a wider view (the 10mm that came with my 130p was like looking through a small keyhole...)  Budget £40 max.  Well, maybe I could push it up a bit higher with a very convincing reason!

 

Thanks in advance.

[John]

Difficult to get a widefield that will work decently well in an F/5 scope for £40 but the best I can think of would be the BST Starguider 12mm which are around £49 new and can be picked up used for £30-£35. It has reasonably long eye relief as well so should be OK for your glasses.

 

[Stu]

Have you considered selling the 40mm to give yourself some more budget? Once you have the Panaview I doubt it will get much use as the afov on it is limited by the 1.25" barrel size. It will also give an exit pupil of 8mm with your f5 150PDS which will be larger than your maximum pupil size and will give a washed out image most likely.

A 12 ish mm eyepiece would be a good choice for DSO observing, with an exit pupil just over 2mm which is often considered optimum for DSO observing.

 

[spaceboy]

As above. £40 is pennies in this game when it comes to wide field eyepieces even for used. BST are very good for the money but your still only talking 60° fov

[mikey2000]

I think I'm revealing my newbie-ness here!  I thought 12mm was quite high magnification but everyone is talking about wide field suddenly.

 

Can I ask about "exit pupil" please.  My (possibly misinformed) understanding is that this is the actual diameter of the cylinder of light leaving the eyepiece.  I'm sure my eyeball can open its pupil to at least 6-7mm (from looking at my eye in the mirror in my livingroom this evening) and maybe wider under a night sky.  So (if my understanding is correct) a 2mm exit pupil is the proverbial eye of the needle peephole.

Is this then why people are mentioning wide field?  As in, high magnification, wide view?

 

Also, I had a quick look at the FLO shop - I don't see BST as a brand for eyepieces.

[John]

You said that you wear glasses and prefer a wider view. I've tried to find an eyepiece at or around your budget, in the focal length you were looking for, that ticks those boxes. A 12mm in your 750mm focal length scope gives 63x which is a medium magnification. 150x - 180x would be high magnification for the scope.

As it happens FLO don't stock the BST eyepieces but they are very good for their cost. This is from a Tele Vue / Pentax user.

[mikey2000]

Thanks John - I'm not going mad then looking for BST on flo.com   I'm definitely using all the right words in all the wrong places here.  Wide field= low magnification (to me) and wide view = whatever magnification but a bigger circle of stuff to look at.  Does that make sense?

 

I probably need educating on all of this and maybe have a few 'bad habits' (or plain wrong 'translations') from my other hobby, DSLR photography

[John]

Using a low magnification does increase the amount of sky you can see. Eyepieces also come with different field widths which could be expressed as normal, wide and ultra wide. It was probably me misinterpreting what you meant as much as you !

Anyway, I'd stand by my recommendation of the BST Starguider 12mm because I feel, for the glasses wearer with an F/5 scope it's about the best 12mm eyepiece that a budget of £40-ish can buy.

[mikey2000]

John,  let's not get into a Humble Contest!   Thanks for the mini-tutorial.   To rephrase my original request, I'm looking for a wide field width moderate magnification eyepiece. (I think!!!)  I will look at other retailers for a BST 12mm. Thanks for the very specific, precise recommendation (hard to get for a newbie with so many variables!)

 

Perhaps everyone can understand my urge for a wide field width.  After all, it's gazing at the big wide sky that drives us to look at it even closer.  Even at high magnifications, I want to see as wide a view as possible! 

 

Side topic:  How long until somene invents a way of creating "array scopes" where we somehow computer-link several smaller scopes, all slightly offset, with cameras in the eyepiece holders and then use a laptop screen to view a somehow combined view...

[Charic]

23 minutes ago, John said:

BST eyepieces .......... are very good for their cost. This is from a Tele Vue / Pentax use

There it is, black & white? I've  found what I was looking for?  

 

49 minutes ago, mikey2000 said:

the 10mm that came with my 130p was like looking through a small keyhole

..........its the same with my scope, but I replaced my skywatcher Super 10 with an 8mm BST Starguider. The difference is big?

I have a 6mm to match my focal ratio, and a 12mm  which is twice the focal ratio of the telescope, the telescopes  sweetspot, the suggested optimal  eyepiece configuration?  This put my 12mm in my Medium bracket.
Your  new scope will have a ratio of f/5. So a 5mm High and a 10mm  Medium is  a suggestion, but if you  purchased the 12mm and 8mm BST Starguiders, you'd be hard pushed in deciding which one to send back, if you were only allowed one!
The wider the field,  the  longer  the  eye-relief,  the better and more comfortable it feels, but  this comes at a price. Take your pick,  BST Starguider or Tele Vue Delos, its a no brainer right, its the Starguider! why? its cheap and does a brilliant job, but for about £ 280 more you could have the wider view afforded by using  say the 12mm  Delos or buy most if not all of the Starguiders?
Your scope is 'faster' than mine by a small  margin,  which can reveal  aberrations  in the optical system, if you look for them? their mainly towards the  outer edges  of your  field of view. But on axis, just about any eyepiece should work.

[John]

11 minutes ago, mikey2000 said:

....Perhaps everyone can understand my urge for a wide field width.  After all, it's gazing at the big wide sky that drives us to look at it even closer.  Even at high magnifications, I want to see as wide a view as possible! 

 

I certainly understand that - I often use hyper-wide eyepieces that give very high magnifications. My scopes are on undriven, alt-azimuth mounts so the wider field of view helps keep objects on view for longer between "nudges"

With such eyepieces the cost has climbed considerably though so keeping your tastes to more moderately wide fields also helpd maintain the bank balance !

[Charic]

There's wide then there's  wide, how much do you/we need? I don't thing everything will look fine  wide-field.
The Moon looks very small viewed through my Panaview with a Sea of space surrounding it, yet at 375x the  surface  craters look stunning, if you can keep up with the pace!

Have you considered wide view binoculars? I have some 8x40s with just a little over 8° angular, and the amount of sky they take in is fine for my needs, however, there is no surface detail,  on the likes of Jupiter,  the reason my telescope exists!

[rockystar]

Have you looked at 2nd hand? Slightly outside your original budget, but there is an ES82º 14mm currently in the classifieds (not mine, by the way. I'm not plugging my own wares)

[spaceboy]

1 hour ago, mikey2000 said:

Thanks John - I'm not going mad then looking for BST on flo.com   I'm definitely using all the right words in all the wrong places here.  Wide field= low magnification (to me) and wide view = whatever magnification but a bigger circle of stuff to look at.  Does that make sense?

 

I probably need educating on all of this and maybe have a few 'bad habits' (or plain wrong 'translations') from my other hobby, DSLR photography

http://www.ebay.co.uk/itm/1-25-12mm-BST-Explorer-Dual-ED-eyepiece-Branded-Starguider-/381664565469

[John]

27 minutes ago, Charic said:

There's wide then there's  wide, how much do you/we need? I don't thing everything will look fine  wide-field.
The Moon looks very small viewed through my Panaview with a Sea of space surrounding it, yet at 375x the  surface  craters look stunning, if you can keep up with the pace!
 

With 110 degrees AFoV and 338x or 430x the Moon looks stunning AND it's easier to keep up with the pace !

But these are not the eyepieces that are being considered here so I'll say no more .....

[Charic]

mikey2000...........spaceboy has added a good link, one I  should have mentioned earlier.

[Ben the Ignorant]

Maybe this, if you want to stick to low budget:

http://www.teleskop-express.de/shop/product_info.php/info/p961_TS-Optics-WA12-Weitwinkel-Okular---12-mm---1-25----60--Gesichtsfeld.html

But the BST if you agree to spend a little more.

[Vicky050373]

Hi there, I have the 32mm Panaview and it is a beautiful eyepiece and it gives lovely views in both my SCT and refractors. As mentioned above, I doubt your 40mm 1.25" EP will get any use once you've experienced the immersive views the Panaview will offer. I would be inclined to put the 40mm in the classifieds and put the money towards another EP that you will get more use out of.

I have the full range of BST Explorer Starguider EPs, and they are lovely little EPs which boast a 60 degree afov. They are nice and lightweight but with a quality feel. Similar to the Panaview, the twist up cup is a really nice feature, and one I prefer to the rubber flip up type. The 12mm is a good choice, however my 15mm and 18mm get equal use. As my scopes vary in FL from 500mm to 2032mm, a lot depends on the scope I'm using as to which EP gets the most use. In your scope a 12mm will be a nice medium power EP. If you go direct to Sky's the Limit shop Alan may well offer a small % discount to order direct rather than through eBay, and you may get a further small discount for ordering multiple EPs. Asking doesn't cost anything.

Good luck, and hope you enjoy using whichever EP you decide to add to your collection next

[mikey2000]

A belated thankyou to everyone that helped to choose the BST Starguider 12mm.   I received it at christmas and it is a really nice piece of equipment.  Reassuringly solid and well made - not a bad start.  Optically, it does a fine job too.  In fact it makes my other EPs seem rather cheap and nasty now (Except the panaview 2" - I really like that one too!)

[Vicky050373]

Pleased to read you like your BST eyepiece. It'll sit well along with your 32mm Panaview to give you a nice range of focal lengths. It'll give you years of viewingpleasure I'm sure  

[Charic]

The BST Starguider 8mm was my first upgrade, it leaves the supplied 10mm for dust! Their 8mm will fit nicely between your 6 and 12mm, even though a 5mm would better match your focal ratio, the 8mm has a little more leeway if/when  x2 Barlowed to 4mm on those special occasions! should you wish to own another Starguider ?

[triton1]

I'm the same as Charic bought the 8mm BST liked it so much I still have it.I was going for the whole set but plans changed.

[alanjgreen]

Your scope has focal length of 750

the 6 gives x125

the 32 gives x23

x75 would be in the middle =10mm

seems to me that a 10mm would be a better size to choose

then I would get something at x175 (which would be a 4mm eyepiece in your scope). What objects are you interested to see? Then we can better determine what would be a good magnification to aim for?

 

[alanjgreen]

I agree with Stu above, sell the 40mm, you do not need it.

i would get a 9mm Celestron x-cel, at 59 pounds it's over budget, BUT has long eye relief for glasses wearers( of 20mm) and 58 degree FOV

https://www.firstlightoptics.com/celestron-eyepieces/celestron-x-cel-lx-eyepiece.html

[mikey2000]

Thanks for the continued advice and thoughts! 

 

Amusingly, I'm finding my 40mm still quite useful - the 2" panaview is undoubtedly more pleasing to look through but the 40mm is less 'faff' when scouting for an object before switching to more magnification.

 

I'm mostly interested in DSO with a particular fondness for clusters.   There's a bit too much LP for nebula spotting here (I still haven't seen M1 for certain...)  I'll see how I go with my panaview and new 2" LP filter once the clouds break.  I'm hoping for some views of Jupiter as 2017 marches on so maybe a nice 4mm is on my horizon :-) (I have a cheap 2x barlow that makes fairly unpleasant viewing after being spoiled with higher quality EPs....)