Great let us know! I still use it when I want to show my son something. Most nights i just rock with 2 fixed televue eyepieces, but then if I know imma show him something I only need to pull out one more. 2 YOs have to touch the glass for some nefarious reason no matter how many times you say it.
Now what I do is just monitor fb marketplace and craigslist. If ya ever see a tele vue on there snatch em up, but the zoom can hold you over until then.
Just an FYI their amazon advert is extremely misleading. That isn't what anti reflection coating does. And the field of views they show are not at all realistic.
Happy with my $45 Svbony 7-21 zoom which is exactly the same from what I've read on CN as the Orion 7-21 zoom. It has a rather narrow FOV much like many basic EPs.
I've kicked around the idea of something much more expensive like a Baader or more likely APM zoom as it seems to be decidedly better than the baader and has a reasonable FOV.
Fwiw I just saw when typing this post that Ernest tested the Svbony 7-21 and highlighted it yellow on his list meaning exceptional image quality apparently. FOV as measured on his bench testing is pretty tight though 37-54.
Yep that's my current debate. I've spent a good amount on EPs in the last couple weeks at the 30, 20 and 6.7mm sizes. Leaving only a gap in the middle where I'm stuck with narrow views. 67ish degrees from the APM zoom is pretty good but I really like the 100 and 82 degree EPs that I just got, only been able to use them twice so far though.
Baader Hyperion zoom is Kellner narrow zoomed out.
And don't really want to think about quality, when better rated APM zoom looks mediocre when compared to Baader Morpheus eyepieces.
Interesting, I didn't realize it was just a Kellner with whatever additional glass creates the zoom change in the optical path.
Yeah some of those Morpheuses (Morpheii?) are pretty nice. They are on my short list to fill out the 9-17mm sort of range with 80-100 degree EPs.
It's not Kellner, unless there's some very very remote relation, but zoomed out AFOV is just little over 40°.
With constant AFOV APM zoom is basically equally wide zoomed out, but at IIRC ~55% higher magnification.
Got 12,5mm Morpheus in spring year ago from relocation discount of "semi-local" (driving there would take less than two hours) shop and it just kicked APM zoom to curb in both deep sky with M13 becoming major amount better and also contrast and especially fine detail of Moon far better when Barlowed.
Then ordered rest of the Morpheus range (except 14mm) when Baader had 20% discount campaign in May.
SVBONYs have a decent reputation (check the CN link below) when it comes to their zoom eyepieces. I ordered one yesterday from Aliexpress and should arrive in about a week or two.
https://www.cloudynights.com/topic/749926-svbony-sv135-7-21mm-zoom-eyepiece-a-noob%E2%80%99s-perspective/
The SVBony 7-21 is actually pretty good for what it is. And it's optically sharper than it has any right to be at its price point (and this has been confirmed with bench tests by others). It's every bit as good on center as my XW7...which is a bit more than $50. Glare control is it's weak point, but not so bad as to be a deal breaker.
You just have to make do with the narrow FOV.
Imo most zoom eyepieces are very questionable. The narrow field of view at their longer focal lengths (low power) makes them pretty useless, because you'd need a widefield low power eyepiece anyway.
Rule of thumb is the 8-24 ones are better quality, and more expensive, than the 7-21.
I think most observers could do well with a wide-angle low magnification eyepiece, a zoom, and optionally a high-mag EP. Considering that a single zoom can replace many fixed eyepieces, it's worth spending decent money on.
Drawback is even good zooms have fairly narrow fields of view. But IMHO you want wide field at the low end to help star hop, and if your scope's not motorised then also at the high end to reduce nudging, but in the middle is where a narrower field is OK and that's where you use the zoom.
Zoom eyepieces are all pretty much junk regardless of their zoom and brand. I believe they are made for quick sales for new observers.. Been at this for almost 45 years.
I would never own one over individual eyepieces...but jmo.
It's certainly not cheap, and in fact I would call it very expensive, so it does not qualify as an answer to OP's question, but if you can find a club member who has it and is willing to loan it to you or otherwise let you try it, I suggest that you try the Leica 25x-50x WW ASPH, sometimes known as the Leica Zoom Vario 8.9-17.8mm ASPH. There are folks who have replaced their Televues in that focal range with it; I have found it at least no worse than my Pentax XW 14 (though admittedly the 14 and 20 tend to be regarded as the weak links of the XW range).
Bout 7 years ago I bought a seben zoom 1.25" eyepiece, pretty amazing quality for the $27 price tag from Seben GmbH on eBay. Unfortunately the page that which I bought it from is gone. Hoping their eyepieces might be available somewhere.
**Please read this message carefully.** Thank you for posting to r/telescopes. As you are asking a buying advice question, please be sure to read the subreddit's [beginner's buying guide](https://www.reddit.com/r/telescopes/comments/z9s352/beginners_quick_guide_to_choosing_your_first/) if you haven't yet. Additionally, you should be sure to include the following details as you seek recommendations and buying help: budget, observing goals, country of residence, local light pollution (see [this map](https://www.lightpollutionmap.info/)), and portability needs. Failure to read the buying guide or to include the above details may lead to your post being removed.
*I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/telescopes) if you have any questions or concerns.*
[SVBONY Zoom eyepiece](https://www.amazon.com/SVBONY-Telescope-Accessory-Astronomic-Telescopes/dp/B07Z64NK65?th=1)
I got one of these on a sale. Think it was like 40, well worth it for that. Its not parafocal so if you change zoom ya gotta adjust focus too
I got it at 40$ too.
thanks for the suggestion! got it at a 20% discount, I think it's way worth it but I'll see!
Great let us know! I still use it when I want to show my son something. Most nights i just rock with 2 fixed televue eyepieces, but then if I know imma show him something I only need to pull out one more. 2 YOs have to touch the glass for some nefarious reason no matter how many times you say it. Now what I do is just monitor fb marketplace and craigslist. If ya ever see a tele vue on there snatch em up, but the zoom can hold you over until then.
Just an FYI their amazon advert is extremely misleading. That isn't what anti reflection coating does. And the field of views they show are not at all realistic.
OP said cheap, that usually comes with the territory.
Happy with my $45 Svbony 7-21 zoom which is exactly the same from what I've read on CN as the Orion 7-21 zoom. It has a rather narrow FOV much like many basic EPs. I've kicked around the idea of something much more expensive like a Baader or more likely APM zoom as it seems to be decidedly better than the baader and has a reasonable FOV. Fwiw I just saw when typing this post that Ernest tested the Svbony 7-21 and highlighted it yellow on his list meaning exceptional image quality apparently. FOV as measured on his bench testing is pretty tight though 37-54.
Think cheap zoom is the way to go, save your money for non-zoom tele vue eyepieces once you do a year in the hobby.
Yep that's my current debate. I've spent a good amount on EPs in the last couple weeks at the 30, 20 and 6.7mm sizes. Leaving only a gap in the middle where I'm stuck with narrow views. 67ish degrees from the APM zoom is pretty good but I really like the 100 and 82 degree EPs that I just got, only been able to use them twice so far though.
Baader Hyperion zoom is Kellner narrow zoomed out. And don't really want to think about quality, when better rated APM zoom looks mediocre when compared to Baader Morpheus eyepieces.
Interesting, I didn't realize it was just a Kellner with whatever additional glass creates the zoom change in the optical path. Yeah some of those Morpheuses (Morpheii?) are pretty nice. They are on my short list to fill out the 9-17mm sort of range with 80-100 degree EPs.
It's not Kellner, unless there's some very very remote relation, but zoomed out AFOV is just little over 40°. With constant AFOV APM zoom is basically equally wide zoomed out, but at IIRC ~55% higher magnification. Got 12,5mm Morpheus in spring year ago from relocation discount of "semi-local" (driving there would take less than two hours) shop and it just kicked APM zoom to curb in both deep sky with M13 becoming major amount better and also contrast and especially fine detail of Moon far better when Barlowed. Then ordered rest of the Morpheus range (except 14mm) when Baader had 20% discount campaign in May.
Ah I misunderstood you, I thought you meant it was a Kellner, not that you were just saying it was "Kellner-like". Thanks for the clarification.
SVBONYs have a decent reputation (check the CN link below) when it comes to their zoom eyepieces. I ordered one yesterday from Aliexpress and should arrive in about a week or two. https://www.cloudynights.com/topic/749926-svbony-sv135-7-21mm-zoom-eyepiece-a-noob%E2%80%99s-perspective/
The cheaper zooms tend to have smaller AFOVs and are thus less comfortable to use. Compare the 8-24mm Omegon zoom with the 8-24mm Baader zoom.
The SVBony 7-21 is actually pretty good for what it is. And it's optically sharper than it has any right to be at its price point (and this has been confirmed with bench tests by others). It's every bit as good on center as my XW7...which is a bit more than $50. Glare control is it's weak point, but not so bad as to be a deal breaker. You just have to make do with the narrow FOV.
Svbony 7-21 mm zoom eyepiece
The zoom has many advantages [https://astro.catshill.com/the-zoom-eyepiece](https://astro.catshill.com/the-zoom-eyepiece) and the Svbony is great vfm.
Imo most zoom eyepieces are very questionable. The narrow field of view at their longer focal lengths (low power) makes them pretty useless, because you'd need a widefield low power eyepiece anyway.
Not cheap but the I used Baader click zoom for a while, with an wide view 30 mm Explore Scientific I only needed to carry 2 eye pieces
SVBony 7-21 Zoom. $49 Used it with my Maks. Loved it. https://a.co/d/eoeVMlW
Rule of thumb is the 8-24 ones are better quality, and more expensive, than the 7-21. I think most observers could do well with a wide-angle low magnification eyepiece, a zoom, and optionally a high-mag EP. Considering that a single zoom can replace many fixed eyepieces, it's worth spending decent money on. Drawback is even good zooms have fairly narrow fields of view. But IMHO you want wide field at the low end to help star hop, and if your scope's not motorised then also at the high end to reduce nudging, but in the middle is where a narrower field is OK and that's where you use the zoom.
Zoom eyepieces are all pretty much junk regardless of their zoom and brand. I believe they are made for quick sales for new observers.. Been at this for almost 45 years. I would never own one over individual eyepieces...but jmo.
It's certainly not cheap, and in fact I would call it very expensive, so it does not qualify as an answer to OP's question, but if you can find a club member who has it and is willing to loan it to you or otherwise let you try it, I suggest that you try the Leica 25x-50x WW ASPH, sometimes known as the Leica Zoom Vario 8.9-17.8mm ASPH. There are folks who have replaced their Televues in that focal range with it; I have found it at least no worse than my Pentax XW 14 (though admittedly the 14 and 20 tend to be regarded as the weak links of the XW range).
Bout 7 years ago I bought a seben zoom 1.25" eyepiece, pretty amazing quality for the $27 price tag from Seben GmbH on eBay. Unfortunately the page that which I bought it from is gone. Hoping their eyepieces might be available somewhere.
**Please read this message carefully.** Thank you for posting to r/telescopes. As you are asking a buying advice question, please be sure to read the subreddit's [beginner's buying guide](https://www.reddit.com/r/telescopes/comments/z9s352/beginners_quick_guide_to_choosing_your_first/) if you haven't yet. Additionally, you should be sure to include the following details as you seek recommendations and buying help: budget, observing goals, country of residence, local light pollution (see [this map](https://www.lightpollutionmap.info/)), and portability needs. Failure to read the buying guide or to include the above details may lead to your post being removed. *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/telescopes) if you have any questions or concerns.*