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Which Svbony Zoom for me?

Beginner Eyepieces
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#1 Bener

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Posted 21 July 2021 - 10:03 PM

Hello everyone,

 

I very recently acquired an AWB telescope and am looking at expanding my eyepiece selection. I was wondering if a particular model may be a better choice for me than the others. 

 

I currently have the two stock eyepieces (10 & 25mm), as well as an older 35 mm Sirius Plossl and a 6.5mm.  I am curious to try one of the Svbony zooms (SV135: 7 to 21mm; SV171: 8mm to 24mm; SV170: 10mm to 30mm) that I’ve read about here, and was wondering if there are any factors that would make one a better choice for me. I am thinking, based on my very limited knowledge —I am a beginner— that I will eventually want an eyepiece or two to complement what I have. I sort of imagine that it might be an eyepiece in the 12-24mm range and one between the 25 & 35mm eyepiece.

 

What would you folks recommend for me among these three? Is there something more compelling similarly priced or for a bit more?  I figure that if I stay with this hobby I will eventually get a couple of higher quality eyepieces, but those would likely not be top dollar units.  I have already “ traded up” a bit in the higher magnification range by getting the Meade HD-60 6.5mm.  

 

Thanks in advance for your time and ideas!
 

 


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#2 vtornado

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Posted 21 July 2021 - 10:44 PM

I would not get the 10x30, because at the 30mm is going to be a narrow apparent field of view.

If you are thinking about using a barlow pick the 8-24 because 4mm is a usable power.

If not get the 7-21 to get slight higher magnification than the 8.

 

Since I don't have these zooms, I cannot state whether one is optically better than another.

I am making my suggestion on only the zoom range.

 

 

P.S.

 

Welcome to the forum.!

 

VT.


Edited by vtornado, 21 July 2021 - 10:49 PM.

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#3 Bkoh

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Posted 22 July 2021 - 01:50 AM

Hello everyone,

 

I very recently acquired an AWB telescope and am looking at expanding my eyepiece selection. I was wondering if a particular model may be a better choice for me than the others. 

 

I currently have the two stock eyepieces (10 & 25mm), as well as an older 35 mm Sirius Plossl and a 6.5mm.  I am curious to try one of the Svbony zooms (SV135: 7 to 21mm; SV171: 8mm to 24mm; SV170: 10mm to 30mm) that I’ve read about here, and was wondering if there are any factors that would make one a better choice for me. I am thinking, based on my very limited knowledge —I am a beginner— that I will eventually want an eyepiece or two to complement what I have. I sort of imagine that it might be an eyepiece in the 12-24mm range and one between the 25 & 35mm eyepiece.

 

What would you folks recommend for me among these three? Is there something more compelling similarly priced or for a bit more?  I figure that if I stay with this hobby I will eventually get a couple of higher quality eyepieces, but those would likely not be top dollar units.  I have already “ traded up” a bit in the higher magnification range by getting the Meade HD-60 6.5mm.  

 

Thanks in advance for your time and ideas!
 

 

10-30: 33-51 deg AFOV. The wide end is used in finding or to observe large objects, either way 33 degree AFOV may be too narrow to be much fun.

 

7-21: 40-57 deg AFOV. Smallest and lightest of the trio, may be better for the AWB focuser although others have reported no issues even with fairly heavy eyepieces (300+g). A bit cheaper than the 8-24. Stated eye relief a little lower than 8-24. 7mm overlaps with your 6.5mm. Good match for a small scope.

 

8-24: 38-56 deg AFOV. Larger, good eye relief (works well with eyeglasses). Costs a bit more. Heavier. Stops at 8mm so your 6.5mm is a useful jump. A more natural "transition" eyepiece between your 35mm and the 6.5mm. My vote is for 8-24. FWIW my SV406P spotting scope came with a modified version of this eyepiece (no filter threads), it works well both day and night with no SAEP, very easy to look through under all conditions.

 

Svbony also has 2 new zooms:

 

SV191 9-27 (40-60 deg AFOV)

SV191 7.2-21.6 (42-65 deg AFOV)

 

The 9-27 has been sold by Hyperflex before, and the 7.2-21.6 by Lunt I think. From their pricing they seem to be marketed as "better" zooms, though of course they are still much cheaper than the Baader Hyperion Zoom.

 

You can read about them here:

 

https://www.svbony.c...k-1-25-/#W9150A


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#4 pregulla

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Posted 22 July 2021 - 02:30 AM

I use zoom mainly for Moon and planets. So I would get one that barlowed have high enough power for that purpose. With a small F/5 telescope 7-21mm + 2x barlow + 32mm plossl should cover all your needs at the beginning. 


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#5 sportsmed

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Posted 22 July 2021 - 09:53 AM

I have a Orion E-series 7-21mm which is the same as the SvBony 7-21mm and its a great zoom. I dont care for the 21mm setting since its to narrow FOV for my liking but if you have or buy a decent 20-25mm eyepiece then the rest of the zoom is usable. But I was surprised how decent the optics were even in the 7mm setting for a cheap zoom. I like having the zoom when I dont want to take alot of EP's with me or if its cold and dont want to take EP's in and out of diagonal. Everyone should have a zoom in the eyepiece case for multiple reasons, very useful at times.


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#6 mikerepp

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Posted 22 July 2021 - 10:15 AM

I purchased a SvBony 7-21 last year, very disappointed with its functionality.  Very stiff to turn and in cold weather, 40°F or lower, it wont turn at all.   Appears that I am the only one that has had this issue from the threads I've read. YMMV.   A couple of specs of dirt on one of the internal lens' that will come in and out of focus as you change FL.


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#7 aeajr

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Posted 22 July 2021 - 11:23 AM

Hello everyone,

 

I very recently acquired an AWB telescope and am looking at expanding my eyepiece selection. I was wondering if a particular model may be a better choice for me than the others. 

 

I currently have the two stock eyepieces (10 & 25mm), as well as an older 35 mm Sirius Plossl and a 6.5mm.  I am curious to try one of the Svbony zooms (SV135: 7 to 21mm; SV171: 8mm to 24mm; SV170: 10mm to 30mm) that I’ve read about here, and was wondering if there are any factors that would make one a better choice for me. I am thinking, based on my very limited knowledge —I am a beginner— that I will eventually want an eyepiece or two to complement what I have. I sort of imagine that it might be an eyepiece in the 12-24mm range and one between the 25 & 35mm eyepiece.

 

What would you folks recommend for me among these three? Is there something more compelling similarly priced or for a bit more?  I figure that if I stay with this hobby I will eventually get a couple of higher quality eyepieces, but those would likely not be top dollar units.  I have already “ traded up” a bit in the higher magnification range by getting the Meade HD-60 6.5mm.  

 

Thanks in advance for your time and ideas!
 

I have the 7-21.  For a short FL scope like yours, that is what I would suggest. Would team up nicely with the SVBony 2X Barlow which I also have.   

 

I use this zoom mostly in my tabletop Dob.


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#8 SteveG

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Posted 22 July 2021 - 08:30 PM

I have the 8-24 and have used it in my OneSky. Optically it's not bad, but in the f5 OneSky it will show astigmatism at the edges for sure. It is greatly improved by placing it in a 2x barlow.

 

I do not recommend any zoom like this for the OneSky, due to the helical focuser. You will have to use 2 hands to focus or change magnification. 

 

From your list, you need an eyepiece between about 9-15 mm. For medium power I use a Nagler 13T6 in my OneSky. 


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#9 Bkoh

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Posted 22 July 2021 - 09:55 PM

...
I very recently acquired an AWB telescope and am looking at expanding my eyepiece selection.
...
I currently have the two stock eyepieces (10 & 25mm), as well as an older 35 mm Sirius Plossl and a 6.5mm.
...
I will eventually get a couple of higher quality eyepieces, but those would likely not be top dollar units. I have already “ traded up” a bit in the higher magnification range by getting the Meade HD-60 6.5mm.
...


You should do more observing to figure out:

1. Which magnification you like to use; and
2. Which eyepiece you dislike the most in terms of AFOV, edge performance, eye relief, ergonomics etc.

That will guide your next purchase. Your collection (6.5,10,25,35) is a good spread, the only gap is at 15-18mm, otherwise the jumps are 50% (6.5-10, 25-35).

The most obvious purchases:

1. Zoom (simplicity, realtime splitting of doubles, different experience etc). Already discussed in previous posts.

2. 15-18mm. Many choices here.

- For semi-premium, I suggest the APM 18mm UFF, the Svbony version which I own is much cheaper than the rest, as low as USD 60 from Lazada. Other choices: Paradigm/Starguider/Xcel LX are in the same price range, you can search CN for reviews (but people mostly prefer other focal lengths in these series).

3. Upgrade an existing eyepiece.

- If the 10 is a Plossl, the limited eye relief and smallish AFOV make it a candidate for replacement. Semi-premium contender: APM 10mm UFF, as low as USD 33 (Svbony branded) from Lazada. I plan to buy this myself. Other well-regarded mid-range choices: 9mm Meade HD-60 / Celestron Xcel LX.

- The 25 and 35 should be fine. If you want to spend, a 24mm eyepiece from ES or APM can replace both the 25 and 35. More affordable choices: ES 26/62, 25mm Meade HD-60 / Celestron Xcel LX.
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#10 Bener

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Posted 23 July 2021 - 01:25 AM

Wow, thank you all very much for sharing your suggestions! I really appreciate your help and believe I understand the basis of the differences in some suggestions offered as well.

 

@Bkoh is correct in pointing out that I should do more observing to help me determine what are my best choices.  Indeed, one of the main reasons that I am interested in getting a zoom at this time is that I thought that obtaining a zoom with the appropriate range will help me decide what fixed focal lens I get next.  Based on my experience with binoculars and camera lenses I know that generally, fixed focal length lenses deliver higher quality views.  So I was a bit surprised to see that the Svbony and its kin are relatively good instruments, especially given their cost.
 

Perhaps I will get one of these Svbony (or comparable) zooms and do a bit of research and look more closely at fixed focal options in the 15-18mm range.  Which of these three zooms would be a good choice to serve in that focal range, the 8-24? I am assuming this model based on poorer performance at the end of range in both directions, which I don’t know is actually correct or not.  
 

I am also now considering a more inexpensive Barlow.  I had been thinking that a decent one would be around $100 but am now considering trying a more modestly priced one, used or new.  Is this combination package of zoom, Barlow & phone mount worthy of consideration?

https://smile.amazon...&s=photo&sr=1-1

 

Is the Barlow in this combination package the same one that you are using @aeajr ?  This might be a good buy if it’s the same Barlow or equivalent.
 

I also see this and see that they have several Barlow options. Are the 2x models functionally equivalent?

https://www.svbony.c...tegories/Barlow

 

Would it instead be better to get the Svbony zoom separately and a different Barlow than the one in this combo package?  I had been thinking that I would look for a used TV or Seibert or similar but maybe one of these Svbony models or a used Meade 122 or Celestron would be fine for a beginner like me.

I think the cell phone mount for pictures in the combo package is this model:

https://www.svbony.c...Adapter-W2546A/

 

Would this work okay for taking pictures with my AWB scope?

 

Finally, @Bkoh is also correct about my current eyepieces.  The 10mm is the weak link. My recently acquired 6.5 HD60 is so very much nicer!  The view I have with the 35mm is very nice, too. I am sort of surprised how nice the views are considering it’s an ancient lens I’ve used for decades in a spotting scope. Even though I feel the stock  25mm is not quite as nice as the 35 mm, it is still a good lens for me at this time. 

 

Once again, thank you all for giving me so many ideas!


Edited by Bener, 23 July 2021 - 01:33 AM.


#11 CeleNoptic

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Posted 23 July 2021 - 02:11 AM

I purchased a SvBony 7-21 last year, very disappointed with its functionality.  Very stiff to turn and in cold weather, 40°F or lower, it wont turn at all.   Appears that I am the only one that has had this issue from the threads I've read. YMMV.

 

No, you're not alone. Mine 7-21mm SVbony does the same thing. It's stiff and even at ~35°F outside it used to get frozen. Optically is fine with good light control though. Overall, the QC at SVbony is a disappointment, but you get what you pay for...


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#12 BradFran

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Posted 23 July 2021 - 02:57 AM

I purchased a SvBony 7-21 last year, very disappointed with its functionality.  Very stiff to turn and in cold weather, 40°F or lower, it wont turn at all.   Appears that I am the only one that has had this issue from the threads I've read. YMMV.   A couple of specs of dirt on one of the internal lens' that will come in and out of focus as you change FL.

Same here. It's usable until around 5C (40F) then it gets so stiff I need to remove it from the focuser to adjust the zoom setting. For under 50 Euro it's well worth the price optically, I just wish it wasn't so stiff. I've had it nearly a year and it hasn't gotten softer with use.


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#13 aeajr

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Posted 23 July 2021 - 03:06 AM

I have the 8-24 and have used it in my OneSky. Optically it's not bad, but in the f5 OneSky it will show astigmatism at the edges for sure. It is greatly improved by placing it in a 2x barlow.

I do not recommend any zoom like this for the OneSky, due to the helical focuser. You will have to use 2 hands to focus or change magnification.

From your list, you need an eyepiece between about 9-15 mm. For medium power I use a Nagler 13T6 in my OneSky.


Good point about the helical focuser. Was not aware the OneSky had this kind of focuser.

#14 therealdmt

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Posted 23 July 2021 - 03:21 AM

Same here. It's usable until around 5C (40F) then it gets so stiff I need to remove it from the focuser to adjust the zoom setting. For under 50 Euro it's well worth the price optically, I just wish it wasn't so stiff. I've had it nearly a year and it hasn't gotten softer with use.

My SvBony 7-21 has been fine down to freezing-ish. Used mine all this past winter without any issues. I didn't monitor the temps involved, but it gets a little below freezing numerous nights, probably more usually it's around freezing or a bit above. So, I'm not claiming to have given it an arctic workout or anything laugh.gif Maybe I was just over your cutoff point, I don't know, but anyway I know my hands and feet sure got plenty cold, but the zoom was working fine


Edited by therealdmt, 23 July 2021 - 03:22 AM.

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#15 BradFran

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Posted 23 July 2021 - 07:27 AM

My SvBony 7-21 has been fine down to freezing-ish. Used mine all this past winter without any issues. I didn't monitor the temps involved, but it gets a little below freezing numerous nights, probably more usually it's around freezing or a bit above. So, I'm not claiming to have given it an arctic workout or anything laugh.gif Maybe I was just over your cutoff point, I don't know, but anyway I know my hands and feet sure got plenty cold, but the zoom was working fine

It could be they use different batches of lubricants... some work fine at room temp, then cease up when it's cold, others go below freezing. It's a good eyepiece either way for the price.


Edited by BradFran, 23 July 2021 - 07:29 AM.

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#16 Bener

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Posted 23 July 2021 - 07:31 AM

I have the 7-21.  For a short FL scope like yours, that is what I would suggest. Would team up nicely with the SVBony 2X Barlow which I also have.   

 

I use this zoom mostly in my tabletop Dob.

Which model Svbony Barlow do you have?

 

 Thank you 



#17 Dobs O Fun

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Posted 23 July 2021 - 08:07 AM

I heard the mention of a barlow. I'm the kind of guy that doesn't mind spending good money on quality. I'm am also new at this.

I bought this exact one and received it a few days ago. https://agenaastro.c...h-t-thread.html

It works fine. For $34 you can save your money for other quality EPs.

On my 1200mm FL I can take my 10mm as a 5mm which is 240x. I see the craters on the moon just fine. You can always upgrade later.
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#18 SteveG

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Posted 23 July 2021 - 12:07 PM

Wow, thank you all very much for sharing your suggestions! I really appreciate your help and believe I understand the basis of the differences in some suggestions offered as well.

 

@Bkoh is correct in pointing out that I should do more observing to help me determine what are my best choices.  Indeed, one of the main reasons that I am interested in getting a zoom at this time is that I thought that obtaining a zoom with the appropriate range will help me decide what fixed focal lens I get next.  Based on my experience with binoculars and camera lenses I know that generally, fixed focal length lenses deliver higher quality views.  So I was a bit surprised to see that the Svbony and its kin are relatively good instruments, especially given their cost.
 

Perhaps I will get one of these Svbony (or comparable) zooms and do a bit of research and look more closely at fixed focal options in the 15-18mm range.  Which of these three zooms would be a good choice to serve in that focal range, the 8-24? I am assuming this model based on poorer performance at the end of range in both directions, which I don’t know is actually correct or not.  
 

I am also now considering a more inexpensive Barlow.  I had been thinking that a decent one would be around $100 but am now considering trying a more modestly priced one, used or new.  Is this combination package of zoom, Barlow & phone mount worthy of consideration?

https://smile.amazon...&s=photo&sr=1-1

 

Is the Barlow in this combination package the same one that you are using @aeajr ?  This might be a good buy if it’s the same Barlow or equivalent.
 

I also see this and see that they have several Barlow options. Are the 2x models functionally equivalent?

https://www.svbony.c...tegories/Barlow

 

Would it instead be better to get the Svbony zoom separately and a different Barlow than the one in this combo package?  I had been thinking that I would look for a used TV or Seibert or similar but maybe one of these Svbony models or a used Meade 122 or Celestron would be fine for a beginner like me.

I think the cell phone mount for pictures in the combo package is this model:

https://www.svbony.c...Adapter-W2546A/

 

Would this work okay for taking pictures with my AWB scope?

 

Finally, @Bkoh is also correct about my current eyepieces.  The 10mm is the weak link. My recently acquired 6.5 HD60 is so very much nicer!  The view I have with the 35mm is very nice, too. I am sort of surprised how nice the views are considering it’s an ancient lens I’ve used for decades in a spotting scope. Even though I feel the stock  25mm is not quite as nice as the 35 mm, it is still a good lens for me at this time. 

 

Once again, thank you all for giving me so many ideas!

All of the budget zooms mentioned will perform about the same at the edges. It won’t be terrible, but not perfect. I would just pick the zoom range you want.

 

You don’t need an expensive barlow. This would be the least noticeable after telescope optics, collimation, seeing, and eyepiece. A $40 barlow will be just as good IMO.

 

I wouldn’t invest much time, money or energy on trying to take pictures through this scope. It’s simply not designed for this.

 

From what you’re saying about the eyepieces, it sounds like you are enjoying long eye relief and larger appearance fields of view, like most of us. Look for eyepieces with large eye lenses. The Astro-Tech Paradigms are a good budget choice.


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#19 CowTipton

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Posted 23 July 2021 - 02:06 PM

I had the Svbony 7-21mm zoom SV135.

It performed quite well in my 8" f6 dob.

 

I had one issue where the zoom stopped working so I opened it up and re-tightened one of the interior screws.  After that it worked fine again.

I had it out in single digit temperatures F° and had no issues both before and after that one time.  I think maybe some grease got under the screw because it didn't lock up, it was actually slipping.

 

I chose that zoom because of how small and light it was.  Optically it was quite good, on par with the Paradigm fixed focal length eyepieces, albeit not as wide of a FOV.

I ended up selling it here on CN because I came into possession of an older MkII Baader zoom and optically it was sharper and had better contrast.  But the difference in price was huge of course.

For the money the SV135 is a very good value in my opinion.  That's my recommendation.


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#20 Rick17

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Posted 23 July 2021 - 08:21 PM

I bought the Svbony 7-21 zoom a few months ago, and like some of the other comments here, mine is too tight.  It is a two handed operation.  It did loosen up slightly after about 2000 reps stop to stop..  The optics seem to be fine, especially for the low price.  

 

I got it for observing the moon and doubles, and I like the zoom for that.  But it is too tight to be useful to me.  I know there are others who haven't had this problem.  It's just the luck of the draw with cheap stuff.

 

Can't say anything about temperature characteristics, as mine hasn't seen anything below 70° yet.   

 

Rick


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#21 teashea

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Posted 24 July 2021 - 08:00 PM

Hello everyone,

 

I very recently acquired an AWB telescope and am looking at expanding my eyepiece selection. I was wondering if a particular model may be a better choice for me than the others. 

 

I currently have the two stock eyepieces (10 & 25mm), as well as an older 35 mm Sirius Plossl and a 6.5mm.  I am curious to try one of the Svbony zooms (SV135: 7 to 21mm; SV171: 8mm to 24mm; SV170: 10mm to 30mm) that I’ve read about here, and was wondering if there are any factors that would make one a better choice for me. I am thinking, based on my very limited knowledge —I am a beginner— that I will eventually want an eyepiece or two to complement what I have. I sort of imagine that it might be an eyepiece in the 12-24mm range and one between the 25 & 35mm eyepiece.

 

What would you folks recommend for me among these three? Is there something more compelling similarly priced or for a bit more?  I figure that if I stay with this hobby I will eventually get a couple of higher quality eyepieces, but those would likely not be top dollar units.  I have already “ traded up” a bit in the higher magnification range by getting the Meade HD-60 6.5mm.  

 

Thanks in advance for your time and ideas!
 

I have all three and the quality is quite good.  It really depends on the magnification you want.  


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#22 Bener

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Posted 24 July 2021 - 10:05 PM

I would not get the 10x30, because at the 30mm is going to be a narrow apparent field of view.
If you are thinking about using a barlow pick the 8-24 because 4mm is a usable power.
If not get the 7-21 to get slight higher magnification than the 8.
….

P.S.

Welcome to the forum.!

VT.

I am leaning towards the 8-24 because I am very pleased with my 6.5, so I don’t need the slightly higher magnification of the 7.

And thank you for the welcome!
 

10-30: 33-51 deg AFOV.

…[SNIP] ….

7-21: 40-57 deg AFOV. Smallest and lightest of the trio, may be better for the AWB focuser although others have reported no issues even with fairly heavy eyepieces (300+g). A bit cheaper than the 8-24. Stated eye relief a little lower than 8-24. 7mm overlaps with your 6.5mm. Good match for a small scope.

8-24: 38-56 deg AFOV. Larger, good eye relief (works well with eyeglasses). Costs a bit more. Heavier. Stops at 8mm so your 6.5mm is a useful jump. A more natural "transition" eyepiece between your 35mm and the 6.5mm. My vote is for 8-24. FWIW my SV406P spotting scope came with a modified version of this eyepiece (no filter threads), it works well both day and night with no SAEP, very easy to look through under all conditions

Svbony also has 2 new zooms:

SV191 9-27 (40-60 deg AFOV)
SV191 7.2-21.6 (42-65 deg AFOV)

….[SNIP]….

You can read about them here:

https://www.svbony.c...k-1-25-/#W9150A


I have eliminated the 10-30 based on several factors pointed out by you and some of the others.

I am leaning towards the 8-24 for many of the reasons that you have pointed out.

I looked at those new zooms, they look great, but I think that I will be happy with either the 7-21 or 8-24, for less money when the savings could go towards a nice 15-19 as has been pointed out.

What does “no SAEP” mean?
 

I have a Orion E-series 7-21mm which is the same as the SvBony 7-21mm and its a great zoom. I dont care for the 21mm setting since its to narrow FOV for my liking but if you have or buy a decent 20-25mm eyepiece then the rest of the zoom is usable. But I was surprised how decent the optics were even in the 7mm setting for a cheap zoom. I like having the zoom when I dont want to take alot of EP's with me or if its cold and dont want to take EP's in and out of diagonal. Everyone should have a zoom in the eyepiece case for multiple reasons, very useful at times.


I agree with you on the utility of a zoom. Yes, the optics typically aren’t as nice as fixed but they can be very convenient.

I am thinking that I can probably use my 6.5 HD60 with the zoom for a slim setup when needed.
 

I purchased a SvBony 7-21 last year, very disappointed with its functionality. Very stiff to turn and in cold weather, 40°F or lower, it wont turn at all. Appears that I am the only one that has had this issue from the threads I've read. YMMV. A couple of specs of dirt on one of the internal lens' that will come in and out of focus as you change FL.


Sorry to hear that you got a lemon! I see that a few others have also gotten units that are substandard. I will be on the lookout for any issues with whatever ep I end up with. May I ask, why didn’t you return yours? Was it a used lens?
 

I have the 8-24 and have used it in my OneSky. Optically it's not bad, but in the f5 OneSky it will show astigmatism at the edges for sure. It is greatly improved by placing it in a 2x barlow.

I do not recommend any zoom like this for the OneSky, due to the helical focuser. You will have to use 2 hands to focus or change magnification.

From your list, you need an eyepiece between about 9-15 mm. For medium power I use a Nagler 13T6 in my OneSky.


Thank you for your input. I understand how the helical focuser does make it challenging to use an eye piece that twists in use. What would you recommend?

I would have to find a particularly good deal or a reasonable facsimile to get a Nagler 13 smile.gif
Any suggestions for reasonable facsimile, even used, for a medium powered ep? Based on what is being suggested, I think I am looking for something in the 16-18mm range. I am happy with my lowest and highest magnification eyepieces for now. So I think getting the zoom and a medium powered ep will work for now. Later, I will look for something in the 10 and 20-25 range to replace the stock eyepieces.
 

You should do more observing to figure out:

1. Which magnification you like to use; and
2. Which eyepiece you dislike the most in terms of AFOV, edge performance, eye relief, ergonomics etc.

That will guide your next purchase. Your collection (6.5,10,25,35) is a good spread, the only gap is at 15-18mm, otherwise the jumps are 50% (6.5-10, 25-35).

The most obvious purchases:

1. Zoom (simplicity, realtime splitting of doubles, different experience etc). Already discussed in previous posts.

2. 15-18mm. Many choices here.

- For semi-premium, I suggest the APM 18mm UFF, the Svbony version which I own is much cheaper than the rest, as low as USD 60 from Lazada. Other choices: Paradigm/Starguider/Xcel LX are in the same price range, you can search CN for reviews (but people mostly prefer other focal lengths in these series).

3. Upgrade an existing eyepiece.

- If the 10 is a Plossl, the limited eye relief and smallish AFOV make it a candidate for replacement. Semi-premium contender: APM 10mm UFF, as low as USD 33 (Svbony branded) from Lazada. I plan to buy this myself. Other well-regarded mid-range choices: 9mm Meade HD-60 / Celestron Xcel LX.

- The 25 and 35 should be fine. If you want to spend, a 24mm eyepiece from ES or APM can replace both the 25 and 35. More affordable choices: ES 26/62, 25mm Meade HD-60 / Celestron Xcel LX.


Thank you! A lot of useful information here. I agree with your assessment of the situation and it is also the same or similar to the rest of the advice here.

I already know that my least favorite eyepiece is the stock 10mm. I much, much rather use my 6.5, and the wider FOV is one of the reasons why. I just used the 6.5 for the first time last night and I was very impressed and pleased by how easy it was for me to track Jupiter with the 6.5. It was much harder to follow Jupiter with my 10.

As you can see from my earlier comments, I agree about needing something in the 15-18 range. I am already looking around and doing some research.
 

Good point about the helical focuser. Was not aware the OneSky had this kind of focuser.


What are the other types of focusers that can be used with the OneSky? I have already experienced a couple of “challenges” with it. I have already applied the Teflon tape and it does work well. However, with a couple of my lenses they really don’t achieve focus until they are almost screwed all the way up and almost out of the helical focuser. My solution has been to use a spacer that I made from some closed cell foam that holds the eyepiece up a few mm from sitting flush in the eyepiece holder. This seems to work by changing the focal distance or something that I don’t really know about…this just works for me.
 

All of the budget zooms mentioned will perform about the same at the edges. It won’t be terrible, but not perfect. I would just pick the zoom range you want.

You don’t need an expensive barlow. This would be the least noticeable after telescope optics, collimation, seeing, and eyepiece. A $40 barlow will be just as good IMO.

I wouldn’t invest much time, money or energy on trying to take pictures through this scope. It’s simply not designed for this.

From what you’re saying about the eyepieces, it sounds like you are enjoying long eye relief and larger appearance fields of view, like most of us. Look for eyepieces with large eye lenses. The Astro-Tech Paradigms are a good budget choice.


Good advice, thank you. Yes, you are absolutely right about enjoying larger fields of view. What a joy it is using my 6.5 that has a wider view than my 10mm

Edited by Bener, 25 July 2021 - 12:44 PM.

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