I am considering this eyepiece and one of the concerns I have is the barrel length. I am so glad that you measured and showed it in the video as I couldn't seem to find this info anywhere else. Thank you!
Thanks for this review. I generally like SvBony products, and Ive been watching for a comprehensive review. The eye relief is a bit of a bummer, but there are almost always tradeoffs. Again, thanks! 😊
A great review sir. I've been a terrestrial photographer for decades now and only very recently into astronomy, but I find the parallels quite interesting. In camera terms of course we refer to fixed focal length as prime lenses, versus telephoto, and in the same way prime lenses offer far superior optics to telephoto, but with less flexibility. The only benefit with terrestrial photography is you can always use your MK1 zoom (walking closer to the object) 🤣 Honestly though, I think there is a place for a variable focal length eyepiece alongside fixed eyepieces. I would agree that the convenience often outweighs the loss of clarity, contrast or resolution. Keep up the great content!
SV215 is best used on scopes ≤7" that are ≤f/5.9, 8" ≤f/5, or 10" f/4's. Both your scopes used to test this zoom are overpowered at its lower focal lengths. If you want a Planetary Zoom for your Mak, use the SV135. For your Dob; the SV191 9-27mm with a 2x Barlow. Not trying to plug Svbony, they've just got a curiously wide variety of Zooms!
@oninoyakamo Thanks for your input! Good insight! I haven't had the chance to test the sv135 zoom nor the sv191 yet, but now I'm curious how they would perform with my two telescopes.
I found the SV215 to be superior to both the SV135 and the SV191 in both sharpness and contrast. I quickly sold my other two Svbony zooms due to the optics not being good enough apart from on axis. The SV215 on the other hand has good all round optical quality. I use it for lunar and planetary as well as double stars. My scopes are an f7 apochromatic refractor and a 12" f5 dobsonian.
They look a lot like the nagler zooms. Definitely a reverse engineering job, and would bet the inner 50 degs to perform almost as wellnas televue, but the outer 5deg is probably not as good. Was that the case? A common theory is that al nagler was trying to design a long eye relief nagler after the type 1 and 2 had short eye relief except for the 13mm and 20mm. The design was not up to his standards outside of the inner 60degrees, so he scaled it down and created the radian, instead of a nagler type 3. He succeeded with the long eye relief nagler type 4, which i had in 22mm for a while. In my f5 dob, without the paracorr, the stars at the edge were bloated, where other nagler designs were much better in that regard. It sharpened up with the paracorr, and televue ads mentioned that the nagler type 4 was sharp to the edge when used with the paracorr. I tried out a celestron 23mm axiom LX which was better at the edge and didnt require the paracorr. This also applies to 24mm meade UWA and ES82 versions of the same eyepiece. I sold the 22mm type4. The svbony clone looks like a good budget option
Nice review and more than complete. I just looked at the SVBony page for the 215 and it looks like they are specifically trying to compete with Televue. I would be interested in this or the Televue but ER is a big factor in viewing comfort. I am amazed they didn't provide 20mm ER which would have made a big difference. I'll stick with DeLite and other Televue eyepieces which I have found to be excellent albeit a bit hard on the budget.
For these focal length i have spent nearly 1500$Cdn for the very best specific lengths i.e. 3.5XW 4TOE 6.5Morpheus. I have looked at some reviews of this ocular and am very interested in your experience with it.
In my f5 150 Newtonian that 3mm is 250x and seeing conditions are seldom that good, but sometimes they are. I have a 3.2 ED Starfinder that also has a 60 degree fov. It is 234x in my scope and I marked my focuser for it, only eyepiece I've done that for. I wouldn't really use the 3-8mm except maybe for my 100mm f4 tabletop reflector it would be perfect for.
Great review Bogdan. This looks like a very nice zoom eyepiece. I am a bit concerned about the eye relief however at 10 mm. Sounds like the eye relief didn’t bother you too much though.
@edf2953 Thank you! The eye relief is definitely a downside, but in my opinion not a deal breaker. In this case observing with the glasses on is not an option, but I got used to it rather quickly and after an hour or so it didn't bother me at all.
Great comparison, im getting a Scientific Explore 4.7 82 after watching this, I've a Skywatcher Skymax 150 and was wondering how it would perform with a high magnification.
Bogdan how is the view comfort compared to svbony 8 24 zoom, the lens look really narrow in diameter, 13mm is small, I ask this because it does not seem like a public friendly eyepiece, I am worried becase if is tight the eyebrows will hit the lens and gone is the view untill you clean it
Hi I very interested in this experience in my travel scope as an all In one option as its only 400mm in length so think this eyepiece could save Me tacking lots of eyepiece and a Barlow lens it looks very appealing
Need Help! Purchased a Svbony SV503 80mm ED telescope and cannot get focus after using a number of Plossl eyepieces. I attempted to focus on Polaris as it is visible from my home. Can you please advice?
@michaelnixon6672 Does the view become sharper as you extend the drawtube but ultimately fails to reach focus or is it the other way around? How much does the drawtube extend on your telescope? It should be ca. 80mm. If it's less, maybe the fixing screw below the focuser assembly is tighten up?
Very nice videos and reviews you make 👍🏻 In regard to zoom eyepieces, I think you should review the APM 7,7-15,4mm zoom. I think it's a real game changer! I initially bought the Baader Hyperion zoom to use with my 16" f/4,5 dobsonian, but the edge of field distortion and narrow field of view (48°) at 24mm was just too annoying. The APM zoom has very high build and image quality, and because of the 66-67° FOV through the zoom range, I get an almost identical field of view at 15,4mm with the APM, as at 24mm with the Baader.
Finding it hard to see a good use-case for a Zoom eyepiece. Maybe for splitting duppletstar doubles where magnification over 250 may be required? Bad eye relief is a serious con in my book. Quantity over quality, I suppose.
@benenneen If you think you will upgrade your Barlow with a better one, then get the 8.8. Otherwise get the 6.7. The 6.7 with a 2x Barlow would be overkill on most nights.
@tongzhou930 The eye relief is way too short for observing with glasses on. The non retractable eye guard won't let you get close enough to see the whole field of view. I only used this eyepiece without my glasses on.
If you have just myopia or hypermetropia, you can just take off your glasses, and the only problem you'll have is that you'll achieve focus at a different point in your focuser. Astigmatism, on the other hand, can't be fixed that way... You'd have to keep the glasses on, and probably use an eyepiece with longer eye relief.
Thanks for your review. This is my comparison between Celestron Zoom Eyepiece 24-8mm and this Svbony 3-8mm FMC Zoom Eyepiece . I am comparing the 8mm zooming power of each eyepiece. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ykmJhX1pExc.html
