Thanks so much for your reply!!!
Yes, I looked it up and u/skul219 is right about my telescope's focal length being 650mm, but its aperture is 130mm (5 in), and I mistakenly wrote 6" in the title.
I want to go all in for 200x. I found this 3.2mm EP on Amazon (https://www.amazon.com/Astromania-58-Degree-Planetary-Eyepiece-Telescope/dp/B013SBTGKC) since I wasn't sure what to look for on AliExpress and have never used it before. It seems to fit all the criteria you mentioned: - Wide angle FOV - Long eye relief - 200x or less - Not a Barlow lens - Not a Plossl type
Could you please send me a link for the HR Planetary 1.25" clones at 3.2mm on AliExpress if you think they'd be better than this option?
Thanks for all your help! We mostly looked at planets the other night, and it was great being able to see Jupiter's moons and the rings around Saturn.
If I could push your patience a little further, what would your opinion be on this item: http://www.amazon.com/Astromania-58-Degree-Planetary-Eyepiece-Telescope/dp/B013SBTGKC/ref=sr_1_4?ie=UTF8&qid=1464183492&sr=8-4&keywords=planetary+eyepiece+1.25
Hello :-)
Good thing you came here :-) Celestron has a lot of stuff, among those a few short "Plössl" that have horrible short eye relief, and simple barlows (increasing magnification of existing eyepieces) that will lower the contrast.
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There's no real way around light pollution; Sky-glow filters help very little, I never really use mine. Getting to a darker location is the only alternative. Some use an eye-patch to shield one eye from direct light.
For planets, it does not matter. But you'd need an eyepiece for planets, as the 9mm just barely shows details at 72x.
For $250, you could get a refurbished 6" dobsonian telescope from telescope.com ;-)
I have a very similar telescope; A 3.2mm-4mm for planets is nice.
HR Planetary @ ebay (China->long shipping times)
http://corvus-optics.com/product/planetary-eyepieces/ (3-4mm not in stock ATM; Agenastro and Amazon have similar, but they cost more like $50)
3.2mm is the absolute useful maximum despite the often quoted 260x for a 5.1" (260x) maximum magnification.
For many deep-sky targets, a 15mm is nice to have;
Corvus does not have it in stock atm, $50+ at Amazon, $46 at Agena Astro
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A larger field of view can be nice; E.g. a 32mm Plössl under dark skies, a 20mm-25mm wide-angle under less ideal condition;
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More optional, but I love the 6mm gold-line for this telescope. The full moon its into view at 108x in these wide-angle eyepieces! (similar to this)
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Does he have a good guide such as "Turn left at Orion" (or Nightwatch, or Simple Stargazing), and a dim red light? And some binoculars?
Clear skies :-)
//(edit: cleaned up the links)
There are not a lot of choices for good quality short focal length eyepieces on a budget unfortunately.
Your options are:
This and hello :-)
The telescope isn't suited for overly high magnifications; You could get a halfway decent 2x or 3x achromatic barlow and a "gold line" wide-angle eyepiece ($25 China, $35 US).
500mm focal length divided by 6mm eyepiece = 83x
500mm/4mm=125x
500/3.2mm=156x
A barlow will ad some chromatic aberration.
The cheaper kit 4mm and cheap Plössl have issues (eye relief, small field of view).
A 3.2mm is already pushing things with this telescope. Aliexpress / Amazon / Corvus optics (sold out)
The 2.5mm eyepiece will give you 200x magnification, but the very short reflector mirror has some contrast issues (required parabolization, coma, large obstruction).
Check if the specifications of this telescope mention if the mirror is parabolic at all, else I would not go past 100x magnification, the contrast will decrease.
The best tool is a book, e.g. "Turn left at Orion" - The missing manual on how to observe ;-)
CLear skies!
Yeah, great :-)
The 3.2mm or 4mm HR Planetary are available from $35
Corvus Optics, USA, these focal lengths are sold out for a long time now.
About the 130/650 (z130, lb mini 130, awb onesky, heritage 130p, slt130, 130eq....) and maximum magnification
http://blog.pixelgiraffe.com/wp-content/uploads/2016/03/130-650-high_3.png
http://blog.pixelgiraffe.com/wp-content/uploads/2015/11/awb_Heritage_Magnifications_small.png
A barlow is another solution to reach maximum magnification, but especially the cheaper ones ad some chromatic aberration. Usually a 3x will give you enough magnification for planets. I have a $10 Chinese 5x barlow (achromatic), and it doesn't magnify too much as the 10mm kit eyepiece is so short and the amount the barlow magnifies depends on the distance between lens+eyepiece.
Older post about the AWB Onesky and it's quirks, some things apply to the z130 as well
Eyepiece comparison for more field of view
Clear skies!
Hi :-)
You should have posted before, we don't bite :-) I hope you got a good price on the Starblast.
> SVBONY
SVBONY is a cheap brand, and they have other eyepieces too.
Those "copper-brim" 62° are not good, unfortunately. I only have the 4mm, but others pretty much confirmed my experience. Never go by Amazon reviews. Yes, they are better than the usual cheap kit eyepieces, but not good.
The way magnification works is the other way around. The 23mm from your link will give you less magnificaton than the 8mm.
450mm focal length divided by 8mm ~= 56x
450 / 23mm ~=19x
Largest overview: 32mm Plössl ($27 at Amazon, under $20 at Aliexpress).
Highest magnification: Possibly a 3.2mm (140x) HR Planetary (under $30 via Aliexpress, eBay, $50 at Amazon). But these telescopes are just not made for overly high magnifications. The F/4 mirror has some down-sides. This is not an ideal planetary telescope.
3.2mm, 4mm HR Planetary
(YMMV, check recent seller ratings)
The 66° apparent field of view "gold-lines" are cheaper ($18-$24/$40), but only available down to 6mm (450/6=75x).
A "barlow" can work too, which doubles the magnification of all your eyepieces... But they reduce the contrast. So a dedicated eyepiece is usually the best choice.
Do not buy eyepeice sets (overrated, overpriced, mediocre at best) or Plössl under 10mm (horrible eye-relief!).
Have you observed with it before? (Align the finder! During the day, at a very remote object, but never look near the sun- permanent eye-damage. )
The 8mm will give you a bit over 50x magnification, enough to recognize the planets, albeit small.
What eyepiece is it?
What you really lack is a overview eyepiece.
Clear skies!
Hi :-)
The AWB Onesky only has the benefit of being more portable, otherwise the closed tube and focuser of the z130 has contrast benefits (as /u/Senno_ecto_Gammat already posted :-) )
I browsed through Craigslist, saldy only the usual stuff. Weak mounts, short bird-jones telescopes... Worth it if you buy a cheap long 114/900 for $50 and build a simple rockerbox.
Telescope.com occasionally has the used/refurbished "2nd" xt4.5 for $180 (contrast benefits for planets, despite the slightly smaller aperture compared to the z130) and the xt6 for $210 (which would be great, but also currently not available). Amazon had a warehouse-deals Skywatcher 8" for $250 a few weeks ago, rarely that happens, too.
The z130 is a solid choice. It's not a 6" or 8" dobsonian, but the form factor and large field of view can be nice.
(I use my AWB with the $19 ikea "Bekväm" step-stool which makes it more sturdy than a 130eq. A better eq mount can cost $200-$250 alone. Thus dobsonians are so popular, especially the taller ones.)
A 3-4mm eyepiece for planets is a good idea, as the kit eyepieces only reach 25x and 65x magnification.
$39, 4mm HR Planetary ebay, China / 3.2mm Aliexpress, China
$49 Amazon USA / Corvus used to have them for $38, but these focal lengths haven't been in stock for months
130/650 telescope & maximum magnification
130/650, Magnification II
There's also the wide-angle (info) 6mm 1 2 3, $18-$36, 108x magnification, can be modified relatively easily to reach 3-4mm.
You can get a Barlow for $10-$30 which will multiply magnification (either 2x, 3x or 5x) but combined with the kit eyepiece contrast decreases a bit. At least with the cheaper Barlows.
4mm "Plössl" eyepieces have a short Eye-relief. Plössl under 10mm are not really great and hard to use. Especially children will find it difficult.
Most children are interested in planets. The z130 or Heritage is not a "planetary expert" but with a bit more magnification it's still nice and beats most telescopes for $100-$200.
TL;DR:Z130+3-4mm
Hello :-)
Good advice from /u/The_Dead_See and /u/sflamel.
The AWB Is a nice starter telescope that won't get boring as quickly as the usual wobbly & small starter telescopes.
In general, you get a larger reflector for your budget. While refractors have some benefits (no obstruction, collimation) aperture is key (and collimation/adjusting not as hard as it may sound).
There's also the z130 which is currently on sale for $179. It's not as compact, but the closed tube has contrast benefits over the AWB, and the focuser is a bit better, too.
As it had been pointed out, 4 is a bit young to really enjoy a telescope. But on the other hand, I knew a 4 year old that absorbed anything space-related, so it really depends on the child.
Still, moon and planets will be most likely the target of interest. For deep-sky you really have to show the child books/images, talk about how far away those are, and what the objects are.
Even in one of these 5" telescopes, the nebulae might be small "smoke rings" or faint smudges. "Isn't it exciting?" ... No. :-) But if a child knows beforehand that the nebula is the remnant of a star that once exploded, or massive amounts of gas where new stars are being born, it's much more interesting.
Same thing to learn about constellations and the night sky in general. Does that look like a dipper, or a bear? Could that one be a swan? Yeah, maybe. But it's much more interesting to hear the story about Callisto and Arcas being changed into bears, and trhown into the sky so hard that their stubby tails got enlongated.
If it's unclear how deep her interest goes, there are indeed telescope in the $100 range (or less), but they perform significantly less well in almost every regard.
For the awb or z130, you will need an additional eyepiece to view the planets. This can be a 3-4mm HR Planetary (from $35, $50 in the US) or at least an achromatic barlow that doubles or tripples magnification (from $10-$20) but reduces the contrast a bit.
http://blog.pixelgiraffe.com/wp-content/uploads/2016/03/130-650-high_3.png
http://blog.pixelgiraffe.com/wp-content/uploads/2015/11/awb_Heritage_Magnifications_small.png
4mm HR Planetary Aliexpress (check seller ratings!) / Amazon
Barlow, Amazon (ideal would be a 3x barlow. There are also cheap Vite 5x barlows, with the 10mm eyepiece they didn't even produce too much magnification, probably due to the short 10mm kit eyepiece's barrel, so it's an option for ~200x magnification).
Do not buy Eyepiece box sets, the short Plössl are almost useless and the sets are overpriced.
Clear skies! :-)
No worries :-)
I have the HR Planetary 2.5mm and I rarely ever use it. I used it with my 76/300 firstscope clone, but it barely made a difference (the image was just duller).
Saturn looked like a small dot with it's rings crude notepad sketch on my knee, Jupiter showed it's two center cloud bands.
The Firstscope may perform better than my no-name telescope (horrible secondary mirror holder, constant collimation issues) but don't expect too much.
The targets I enjoyed the most where open star clusters, for example
Plejads
Others such as M44
They benefit from the large field of view the Firstscope gives at lower magnification :-)
Oh, and of course double star Albireo and Eps Lyr.
The ring nebula was visible, but it was just a smudge.
Andromeda an oval faint glow. M81/M82 a nice pair with slightly different shapes.
It's probably best to discuss the planned observing night with your nephews before-hand, as the faint deep-sky objects can be underwhelming, especially in the small table-top telescope. It's much more exiting if you watch a video with them about what these targets actually are, look them up in Stellarium, so they know what they are seeing. :-)
The Heritage comes with a 25mm that's not all that bad, and the 10mm is kind of usable. It's still MUCH better than what came with my firstscope clone :-)
There are also the ...let's call them "Copper line"... eyepieces. Link. I have the 4mm, it 's plastic-y, the eye-relief is short (not as short as a 4mm Plössl's though), but they could be some kid-friendly eyepieces. But They won't be much of an upgrade to the firstscope kit eyepieces I guess despite having a larger apparent field of view.
The HR Planetary 3-4mm
Corvus Optics (USA) has the 2.5mm in stock, the 3-4mm are sold out for months and months. I do not recommend the 2.5mm.
Agena Astro has them for $55, and also the slightly better Starguider Dual ED for $60. But IMHO that's a bit much for these small telescopes ;-)
For $18 you can get the 6mm Gold-Line at Aliexpress, $45 at Agena Astro, sold out forever at Corvus Optics, and $36 (sometimes $30) at Amazon. The 6mm can be modified to 3-4mm relatively easily. Basically think of it as an eyepeice with a barlow in it's barrel. You can unscrew them and change the distance / tube-length, which results in more magnification.
So if you are looking for a budget-budget solution, that's a great one.
Of course you can also get a cheap achromatic barlow for <$20, but it will ad some chromatic aberration.
To echo what others have said, the 2” eyepieces and 2” diagonal mainly help with low power wide views. 1.25” eyepieces are fine for high mag views of planets because you don’t need a wide FOV.
I have also heard that orthos are great for planets. I have not tried any, so I can’t recommend any specifically.
As for focal lengths: - my starting off planetary EP is a 15mm, this will give you 135x, which is plenty to see detail, and will give good views even during less that ideal seeing - my 12mm is my workhorse, gives 170x, provides great viewing most nights - on rare nights I have had luck with an 8mm, but this has only happened twice, 254x - maybe a 10mm would be a nice middle ground between 12mm and 8mm, 203x, would probably work on any night with good seeing, I don’t own one and therefore can’t personally recommend one
Budget options: These 58° Planetary EPs are often recommended as quality budget EPs. I recently bought these 60° Dual ED EPs and have been really enjoying them.
If you go with the z130:
For the 6" dobsonian,
Hello :-) At 75x the planets will be visible but a bit more magnification will be nice to have. With a 6" reflector and typical see in conditions, 200x is a useful magnification to have. Even at 200x and more Mars is a tough target, it's apparent size is small. Atmospheric seeing has to be very good.
A 4mm (126x) "HR Planetary" eyepiece (or a 3.2mm->234x when seeing allows) is a budget eyepiece with a decent eye relief and apparent field of view.
A barlow can be nice, too, but a decent one costs nearly as much as the eyepiece which would offer a bit better contrast and apparent field of view.
For planets, light pollution plays no role. For deep-sky, it does :-)
Clear skies!
Hello :-) Glad you could get it to work! I think /u/sflamel described the finder alignment though ;-)
A barlow a) reduces the contrast a bit, and b) kit eyepiece + barlow is not ideal (apparent field of view, eye relief), and c) a 2x will still not give you the maximum possible.
A 3.2mm-4mm HR Planetary is the best way to go (1 2 3), or a 3x barlow. The barlow would be the budget solution (ebay/China)
DO not get a 6.4mm Plössl. Short eye relief is a pain. Also, for $25-$35 you can get a "gold line" 1 2
More magnification is not always better. The image will get dim, and the atmosphere limits what's possible. A 3.2mm is already pushing things, a 2.5mm not really great ( I rarely use mine)
http://blog.pixelgiraffe.com/wp-content/uploads/2015/11/awb_Heritage_Magnifications_small.png
http://blog.pixelgiraffe.com/wp-content/uploads/2016/03/130-650-high_3.png
(afov)
The 10mm will give you 65x - enough for a bit of planeary detail, but a shorter focal length is nice to have.
About maximum magnification:
http://blog.pixelgiraffe.com/wp-content/uploads/2016/03/130-650-high_3.png
http://blog.pixelgiraffe.com/wp-content/uploads/2015/11/awb_Heritage_Magnifications_small.png
Will you travel by car? Backpack? Is canceling the order an option for you? Or taking along something like a box, beverage crates, Bekväm etcetera?
Clear skies!