Eyepiece sets

[cowmoon]

Hi everyone,

Yesterday I picked up a telescope from Gumtree. Its a Tasco Galaxsee, F=700mm D=76mm. Some pics.

Didnt really know what to expect but for £15 I didnt expect much. It only came with a 20mm lens so I think the first thing to do will be to buy some more.

Ive read through the eyepiece sticky and had a search around on amazon and ebay for something suitable and ive found some kits which seem to cover everything i thought i would need.

Do the eyepiece sets on amazon provide good value for money or am I better buying separately? I was looking at this one in particular but there are others around.

In the future i'd be looking to buy another telescope and so i'd be willing to spend more for the ability to reuse the same lenses in future upgrades.

Basically just looking for some advice on what people with experience would do in my situation.

Thanks

[Andy_E]

Eye piece sets like these do seem to offer good value for money, but I deeply suspect that only half of it would ever get used. If you're after buying some eye pieces (EPs) that you will be able to keep once you upgrade your telescope (which I imagine will be sooner rather than later) then I can highly recommend the BST starguiders (available at skies the limit atro on ebay). At £49 delivered they offer excellent image quality per £. Perhaps a good line up would be an 8mm (giving 87.5x magnification in your telescope) and  12mm (giving 58x)... complementing your 20mm (which gives 35x). I seriously doubt you'll be wanting more than this at this stage. Best advice; use the £30 spare to put towards a larger aperture telescope... perhaps something like this http://www.firstlightoptics.com/dobsonians/skywatcher-heritage-130p-flextube.html.  Hope this helps a little and clear skies

[Qualia]

Ay, + 1 for Andy's advice.

[Charic]

cowmoon..... as Andy_E points out, Starguiders are a perfect choice, its the brand I`ll be investing with, however, I wouldnt spend £130 on a lens kit for your telescope! Your scope has limits due to its specification, and because of those limits will affect what you might expect to see? Any lenses you do purchase can be used on your next scope. If you need to buy another eyepiece  for your telescope right now, get something from ebay second hand, around the 9mm size for your f/9 scope. F700/D76= Focal ratio  f/9.2  Use this measurement as a guide to your Highest powered lens, so maybe an 8mm or 10mm would be fine. A type of lens construction called a plossl is a  general standard lens. Meade(amongst others) make them. Get a Meade 4000 series for example. keep the 20mm as your wide angle/low magnification for now, and once you`ve done your homework on this subject, you`ll be ready for your next scope. Maybe others agree, this telescope wont do justice to that set until you get some more aperture. Im sure your scope will be good for Lunar viewing. take care.

[wookie1965]

+1 for the BST`s they are brilliant eyepieces for the money.

[mitchelln]

I bought that Celestron kit in when I first got back into Astronomy. Funnily enough they were intended for my old Tasco. First problem I hit was that my Tasco used 0.965" sized eyepieces instead of the more standard 1.25". Yours does look 1.25", but you need to check that.

Re. the Celestron kit. The 113 and 7mm eyepieces were pretty good. The 8 and 6mm less so and the Barlow is rubbish. The filters add nothing to the party either. I suspect you would not get much use out of the 32mm either as it would provide very low magnification. Best to pick and choose lenses I think.

[avtaram]

That looks similar to the Celestron 76 AZ that I have.

I would go with Andy and Charics advise.

Avtar

[Naemeth]

When I was first looking at telescopes, I thought about an eyepiece kit. However, as I found out, it's rare that you actually use all the eyepieces in the case, and it's far better to spend a bit more per eyepiece and get much better views .

[cowmoon]

Thanks everyone for the responses. Funny you should mention the 130p Andy because I was intending on buying the EQ-2 version before I saw this one, still probably will by the end of the year but for now this will do to test the waters.

I think i'll start with one of the suggested lenses then. I see on the "Skys the limit" ebay page they have the 12mm but no 8mm, do they come into stock often? Out of choice if I was to purchase one of them to start with would you suggest the 8 or 12? As a side note I have a feeling this 20mm is Rubbish.

Also as for the Meades, I see some 9.7mm  on ebay for between £30-40 and some 12.4mm for close to £50. What sort of price are they worth vs the starguiders?

[cowmoon]

Doesnt seem I can edit so sorry for double post but I just thought to mention again I'd intend on upgrading to the 130p (EQ-2) if that makes any difference on which eyepiece to go for.

[spaceboy]

Result with the scope cowmoon, not bad at all for £15

If I may make a suggestion that goes slightly against the grain on this one as it is often thought by many that fixed focal length eyepieces hold an optical advantage over zoom, but have you considered a zoom eye piece http://stargazerslounge.com/topic/154398-seben-zoom-8-24mm-cheap-zoom-eyepiece/ it wont break the bank and it will offer up several focal lengths. The reason why I present this idea is because I often use a 60mm and 90mm refractor for both night and day (solar) observing and an 8-24mm along with a x2 barlow pretty much covers every magnification needed to view what can be viewed with a of a scope these sizes. The targets most suited being the moon and planets.

Should you decide to upgrade your scope in the future at least you will know exactly which magnifications you prefer to use as zoom eyepieces are not just fixed but variable through out the whole 8-24mm increments.

[cowmoon]

Hey spaceboy thanks, thats a great idea. I hadnt even considered that to be an option and it certainly makes sense in my situation. Any suggestions on where I might get one and how much I should expect to pay? They are on Amazon for £56 delivered. Are there any opinions on the sebem vs the Skywatcher? Seems the skywatcher is a few pounds more. Also there is a 7-21mm for £40 if that would be a better option. Now I have to research a whole new line of eyepieces lol. Lastly any suggestions on which barlow to go with it would be welcome.

[Schorhr]

+1 for the heritage, it will show more then your current telescope can with all the eyepieces in the world ;-)

EQ1/2 mounts are to weak for almost any telescope they are bundled with (except small Maksutov telescopes)...

Your telescope is not bad at all, but with higher magnification you will note that the mount is the weak part of the set, getting Saturn, Jupiter or such into the view at 100-140x will be nerve wrecking.

A dobsonian mount can solve this, and you can build one for 4gbp/5eur, without any fancy tools ( http://www.ringohr.de/tmp6//sky125900_2.jpg right side ).

Regarding planets and deepsky, the 130p will show much more detail;

If you can stretch your budget, go for it ;-)

For the 76/700, the 8-13gbp Plössl are a good deal, and also the 66 degree wide angle eyepieces for 27gbp perform well at that telescope's focal ratio.

You just need a eyepiece for overview, one for planets (~140x / ~5mm with your current telescope, or a 10mm and a 2x acromatic Barlow for 15 €).

Quick sketches; 76mm telescope on Saturn

http://www.ringohr.de/tmp6//2013-05-04_Saturn-h76p_contrast.jpg

130mm telescope

http://www.ringohr.de/tmp6//saturn_small_130p_260x.jpg

Jupiter

76 http://www.ringohr.de/tmp6//2013-05-05_Sketch2_76_jup.bjpg.jpg

130 http://www.ringohr.de/tmp6//2013-05-04_Jupiter130p2_sm_str.jpg

Galaxies are difficult, results may vary depending on conditions, light polution and telescope collimation...

A 76mm will show bright objects such as the Orion nebula, but already ring- and dumbell nebula will show their structure so much better in 130mm, and on planets you can magnify higher before the image gets too dark and blurry.

http://translate.google.com/translate?sl=de&tl=en&js=n&prev=_t&hl=de&ie=UTF-8&u=http%3A%2F%2Fwww.binoviewer.at%2Fbeobachtungspraxis%2Fteleskopvergleich_deepsky.htm

So 5/6" starts to show the first details in nebulae and galaxies, better 8";

http://clarkvision.com/visastro/m51-apert/

This is the reason why so many start with 8", but really, 5" is a good compromise, especially if you have to get away from a light polluted area.

http://clarkvision.com/visastro/m51-apert/

Don't get me wrong, I don't want to discourage you. I started with the same type of telescope, and it was enough to get me interested.

Just don't spend too much money on accessories;

Get one or two Plössl and a barlow for your kit if you want, it will give you much nicer views then the 20mm (probably a Kellner ep).

25 or 30mm Plössl for the maximum field on the 1.25" focuser

~28 / 23x magnification

(The 30mm does not have an eyecup, but can be made out of foamsheets or pipe insulation)

http://www.ebay.co.uk/itm/Orbinar-Plossl-30mm-Teleskop-Okular-31-7mm-1-25-4-Linsen-/360459084615?pt=DE_Foto_Camcorder_Okulare&hash=item53ed092347

10mm Plössl, ~70x http://www.ebay.co.uk/itm/Orbinar-Plossl-10mm-Teleskop-Okular-31-7mm-1-25-4-Linsen-/200760826296?pt=DE_Foto_Camcorder_Okulare&hash=item2ebe4719b8

ACHromatic barlow

http://www.ebay.co.uk/itm/Teleskop-Service-Barlow-Linse-2x-1-25-31-7mm-fur-Einsteiger-Teleskop-2BLK-/390656803342?pt=LH_DefaultDomain_77&hash=item5af4f5c20e

http://www.ebay.co.uk/itm/Achromatische-Barlow-Linse-BA2-2x-fur-Teleskope-31-7mm-/200607942106?pt=DE_Foto_Camcorder_Okulare&hash=item2eb52a45da

I have cheap Orbinar plössl and barlows, of course they are not perfect, but they are astoundingly good for the price.

These are great budget eyepieces http://www.ebay.co.uk/itm/wide-angle-eyepiece-1-25inches-66-degree-F-20mm-/140600338633?pt=UK_Telescope_Eyepieces&hash=item20bc6ee8c9

Though not as good as the bst or tmp planetary eyepieces regarding outer field sharpness - But amazing wide angle eyepieces for a low budget. Even though I have three TMB eyepieces, I still use the 6mm of those.

I have one of those zoom eyepieces. They seem nice at first, but their apparent field of view is so narrow on the longer focel length, that it does not make more sense then getting the cheap Plössl from the same company. Performance is similar.

[cowmoon]

Thanks Schorhr, fantastic post.

The reason I would go for the EP-2 mount is because I would like to take it out into a field etc, am I right in thinking the Dobs stand would be unsuitable for that type of use? Is the ep-2 stand for the 130p notoriously bad? I do love the look of the heritage scope and its compact size, but thats all for a later date.

I'll have a good look through the lenses youve posted and try to get it clear in my head what i'm after long term. I'm thinking that a zoom lens will still be useful even when I have upgraded to better individual lenses/scope whereas the cheaper plossl lenses probably wont be and thats swaying my decision right now. What i'm thinking right now is a zoom lens, a barlow 2x and a decent quality wide-angled plossl (possibly 20mm or higher). That would cover me pretty well I think and leave me with some useful lenses in the future. What do you guys think?

[Schorhr]

Hello,

the eq-2 mounts are so weak even ad moderate magnifications it will shake a lot. I Do have a few Gif-animations of a 130/650 an a Astro3 (slightly more stable then the eq2), I can re-upload them if you'd like.

I thought the Same thing when I started, and the Zoom eyepiece was the First One I bought. Luckily, I got it used for a good price.

They aren't much else then a Plössl with movable barlow element.

As the zoom eyepieces cost around 45£/50€ plus shippimg, I would strongly reccomend getting two of the 66 degree eyepieces and a barlow instead.

The overall performance and views are much better in my oppinion.

In fact, most of the time I leave the house with just three eyepieces in my pockets, usualy that'll cover most targets. Zoom does sound nice and we are so used to it due to digital cameras, but actually it can be quite good to focus on an object in a fixed magnification. With a Zoom I tend to re-adjust all the time.

There are amazing zooms to get the best out of high magnifications to adjust to the current conditions, but they cost yet a bit more.

A dobsonian just stands in the grass, it has a low center of gravity and a sturdy base, this is what makes them so appealing.

They are in fact lighter then a similar telescope on a STURDY eq-mount, easy to set up, and both solid and easy to turn. Even tracking planets at 200-300x is not hard.

The heritage is a bit of an exception as it's rather low to the ground. I take along a collapsible camping stool or just a foam seat pad to sit on the ground. But the heritage is one of the few telescopes you can also use on a table on your balcony and it's set up time is a few seconds, a minute tops when checking collimation of the mirror. But it keeps collimation well even after transporting it by foot... The largest telescope in the price region you can carry like that, a 6" or 8" dobsonian already requires a car or bike trailer.

The Heritage comes with two Plossl-Like eyepieces by the way, while cheaper entry level telescopes come with Huygens or Kellner eyepieces, often with plastic lenses

Oh, and do make sure the focuser tube diameter is 1.25 inches, not 1", as some older production telescope used those and it's hard to get decent 1" eyepieces for a good price.

Regarding eyepieces and aparent field of view;

Get the free Stellarium.org and set up your telescope in there (ctrl+o, alt+o, rightclick menu, theres a manual wiki on their site).

It will show overly realistic views (photos), but the field of view simulation helps deciding on eyepieces.

If you don't want to bother with Stellarium or if it's too complicated, try

http://www.12dstring.me.uk/foveyepiece.php

24mm with 40 degree afov is no fun, and especially the overview magnification should show more field... It makes finding objects easier.

Set up a 24mm 40deg and 8mm 60deg for the zoom's range.

Also set up a 20mm66deg and a 9mm66deg for comparison.

And 30mm52deg (plössl).

Please note that Plössl have a eye relief about as long as their focal length, so under about 10mm they get difficult to view through.

The Modern eyepiece designs of the 66deg and tmb/bst eyepieces and the zoom, too, have a barlow element to reach higher magnification and don't suffer of this problem.

I know I'm probably getting on your nerves, but it would be best if you just get the inexpensive but usable barlow for your current telescope which was a good deal, then you have 35x and 70x, and consider saving the rest for a largere aperture telescope.

Sure, 3" to 5" does not sound like much of an upgrade, but it IS!

As the mirror surface area is almost three times as large, it makes faint galaxies visible and shows more details and structure on the planets, plus you can magnify so high the athmosphere/seeing conditions are usualy the limiting factor, not your telescope :-)

Now I'll shut up, I promise ;-)

[Reeny]

..................Basically just looking for some advice on what people with experience would do in my situation.

Hello Cowmoon.

I have that exact scope under a different name (Telstar).

The scope can only cope with 120-140 magnification.

175x is do-able, but always seems to be a little bit hazy.

I use the standard 20mm (35x) / the Rev 9mm (77x) / and the Rev 12mm with x2.5 barlow (146x)

I suggest a 5mm BST ED eyepiece for 140x

and something around 10mm for 70x

= 35x  /  70x  / 140x

Don't go for a barlow if you can get the correct sized eyepieces, the scope doesn't like Barlows.

It blocks too much light and gives you more opportunities for optical errors.

The glass between you and the mirrors the better.

If you are starting out from scratch, have a look at the revelation package for £138. It comes with:

Plossl 9mm

Plossl 12mm

Plossl 15mm

Plossl 20mm

Plossl 32mm (projection / visual)

Barlow X2

T adaptor 1.25"

ND96 Moon Filter

#11 Yellow Green

#25A Red

#47 Violet

#82A Light Blue

Lockable aluminium case (with die cut foam)

With the above kit you will be able to make use of everything, including:

32mm (22x) / 15mm (46x) / 9mm (77x) / 12mm x2 barlow = 6mm (124x)

I bought individual Plossl's at 9mm / 12mm / and a 2.5 Barlow for £95.

I could have had all the extras and a posh case for another £40.

[Reeny]

Typo correction - should say

"The less glass between you and the mirror, the better"

[Andy_E]

I'd still recommend the 'less is more' approach. Personally, I'd far rather have two good quality EPs than a whole set of average ones plus a set of questionably useful accessories. As for which scope you decide to upgrade to you can decide that in good time (the 130p is only a suggestion) based on what you want from it. A decent  8 and/or 12mm EP(s) will remain in your arsenal for a long time.

[cowmoon]

Not getting on my nerves at all lol. I find all this very helpful and it gives me a lot to think about. One thing I hate is spending money I later regret so taking the extra time to get the right equipment is worthwhile to me.

The thing that puts me off the dobsonian stands is the height, i'm 6'4" so the idea of spending time crouching on the ground doesnt appeal to me. Its also very hilly near me so a stool or table is probably not an option unless the dobsonian stand is okay with being on quite a slope. After watching some videos of the stand in action it certainly performs very smoothly and with little effort so It will be something to consider more carefully if and when I decide to upgrade.

I tried them out in Stellarium and I can see what you mean, the 40deg fov is not perfect but from what people have said the Seben lens at 8mm actually outperforms the £50 8mm BST starguider and combine that with the wide angle 20mm you suggested I feel like I have every base covered. The problem I see with buying the budget plossl lenses is that when I come to buy something like the heritage I will want to buy better eyepieces anyway  and that would make the ones I have redundant, whereas I would buy the zoom lens with the intention of it being the only one I buy and it would hopefully still serve a purpose beyond this current scope. The only downside I see for buying the zoom lens is the price because I could also buy a 12mm plossl instead but would that be better? I'm not sure. But anyway, its something i need to sleep on and hopefully there will be some more opinions voiced to make the decision easier.

[John]

Fixed focal length eyepieces are usually better than their zoom equivalents. The exception is when the zoom is a rather special one such as a Nagler or Leica or possibly a Pentax.

You say  "...One thing I hate is spending money I later regret so taking the extra time to get the right equipment is worthwhile to me.."

Buying a low cost zoom is a compromise so it's worth being aware of that.

[Charic]

cowmoon......... A zoom may help you decide on the best result through the viewfinder, and could also become your only lense, but a primary lens of the same selected focal length should always be a better choice (as John pointed out) If your intent on getting the D-130mm F-650 f/5 telescope, I would still look at two lenses. The high power lens at around 5-6mm to match the f/5 ratio and a low power lens based on  D-130/ 4mm ( average exit pupil size ) giving around 32mm lens (but to stay within the 1.25" [31.75mm] barrel size, stay around the 20-25mm lens size).
There is so much to learn, and when you stated, you`d just collected a scope for £15, Im suspecting this is all very new to you. You will get there in the end, there`s just so many decisions to make. I bet if we had the same telescope and eyepiece, and we went away to set up the scopes, we would still see a difference between the two? On paper, there are technical reasons for everything and why it works, but at the end of the day, its all down to the user. If someone spends £150 on a lens, but their optics are not correctly collimated, they wont have as good a view as you`d get, with your properly collimated telescope. There are lenses out there costing £500 a piece, and i`d love to own a set, but it wouldnt do them justice on my 8" mirror, I`d feel that the telescope was now inferior to the quality of the lenses, and so on. My Choice of aperture was based on Patrick Moore saying 6" minimum, and whereas bigger is always better with aperture, storage space and costs are bigger too. so Im happy with the 8" I have, and dont forsee any changes for a long time. Any lens you buy thats been highly recommended, will always re-sale should you have to.

[Concept]

Hi,

I would recommend getting quality single eyepieces otherwise (and I have seen this happen) you may find yourself getting magnification hungry. This is where you are always wanting to use the highest mag you have, the downside of this is possibly a too dark an image and a drop in the quality of that image.  This then leads to "I got to get a bigger scope now" or you lose interest.

Get a decent mid range eyepiece and learn to see whats out there, magnification isn't everything.

Hope this helps

Trev

[Schorhr]

Indeed, at the short focal length the zoom is Not Bad, but a long Time I just used a 8mm and 20mm eyepiece, nothing inbetween (and with the short focal length of the Heritage, got away with it).

if height is an Issue, a 6" or 8" dobsonian are a much better solution, or a Heritage and a tranport Box to put it ontop, or a 130p on a sturdy EQ mount, meaning at least a neq3 (170£) or One of the skywatcher goto mounts for even more.

As you See a Good mount can cost more then the telescope itself ;-)

The common 6 and 8" dobsonians are close to 1,2 meters long, comfortably usable with a chair, but can't be carried around for a mile or more.

eq mounts will cause your focuser to rotate to odd positions, can be quite anoying as well.

The tripod is easier on uneven ground, but a dobsonian and a piece of Board or rock can solve this. Many cary along something the Level it out roughly, it does Not have to be perfect (in contrast to an eq mount alignment).

The heriage's Base is small enough so i usualy find a Spot to place it, but I have used it on slight slopes as well.

The thing is if you where going to buy a Set/case of eyepieces for 137£ or so, you could afford a telescope with two kit eyepieces and a barlow.

Half of the stuff in those sets won't Get much use, some is even questionable...

And if you want a case, the cheap make up aluminum cases sell for a few quids/bucks/euros in a Dollar störe and eyepieces can be fitted with a Camping mat (cut it to size, cut holes in it, multiple layers, works well.

As I said I have the zoom and if you can Get it used go for it, but if you just use the 8mm and perhaps up to 12mm or so until the view gets narrow, Get the 9mm 66deg eyepieces as it will have more field then any of those, even the 6mm probably ;-)

I find it easier to buy the telescope first and then upgrade eyepieces after the piggy bank is full again ;-) But there is no wrong way of course.

The thing is that all the eyepiece and dobsonian discussion aside, you won't be happy with higher magnifications on the current mount unless you build a different mount.

The reason those telescopes sell so cheap (I got mine for about 5£ used back then) is that they are the reason so many kids loose interest in this exciting hobby.

Also the small finder scope make it hard to actually find things. They are a bit small, have a narrow field and do cause more trouble then they are worth.

Many telescopes now come with a red dot finder that's intuitive to use and you just point and look through at low power.

So overall the heritage has about 50£ worth of accessories plus a decent base, so a better deal then the eyepiece case.

if you consider getting a barlow anyway, as suggested, get it as the only thing for now, a big mistake I made was to get all kinds of accessories at the beginning.

[Reeny]

The Celestron and Revelation packages appear to contain the same equipment.

The plossls should be OK.

They will be excellent on the 700x76 scope - but unknown on anything bigger, better

However, if the 2x Barlow is the single element type - it will be useless.

I have a single element 2x, and the 3-element Revelation 2.5x.

The Revelation out performs the cheapy by far.

So the filters and barlow are unlikely to be used.

That leaves a selection of 5 plossls for £130 - when you only need 2.

To go with your 20mm, I would get the BST 5mm for 140x mag / and some thing around 12mm (58x mag)

You can get the 25mm BST at a later date as well.

That will give you 28x / 58x / 140x for £150 - all that you need.

Don't get a £40 Barlow just yet.

You don't need one.

And it won't focus down far enough to fit in the eyepiece focus tube.

I needed to modify my scope to accept the 2.5x Revelation.

[Reeny]

Maybe it would be best to borrow some eyepieces to test the water regarding sizes.

Also - a £10 water butt stand has been sugggested to mount the dob higher up off the ground.