SVBONY Telescope Lens 4mm Telescopes Eyepieces Wide Angle 62 Degree Aspheric Eyepiece Fully Coated lens for 1.25" 31.7mm Astronomic Telescopes

Good quality, I could see Alpha Centauri A and B both with this eyepiece on the other hand 20mm and 10mm eyepieces couldn't separate this twin star adequately enough. Cons: I found a small dark spot in its optics but it did not hinder the view substantially. Will try it on Jupiter and Saturn asap. Bang for buck

Excellent. Center portion CA well controlled. Nice to see highly magnified image, pls note brightness will reduce according to magnification

Nice to eye relief

Excellent lens. Worth the money spent

I tried it for several nights. Tried to capture mainly 3 planets. Jupiter, Saturn, Mars. Saturn was a bit blurry but you could identify the rings and the gap between rings and planet. Jupiter and Mars were blurred like you are focussing on something very close, and the image was never narrowed down to a sharp image.

pas très lumineux

Really surprised at the overall quality of this very affordable eyepiece (EP)! Wide Apparent Field Of View (AFOV) of 62° and sharp across most of the field. Only thing that could be better is the Eye Relief (ER). To get the full AFOV, your eye needs to be pretty close to the lens. However, this being a high power EP at 4 mm, the ER for this level of magnification naturally won't be great for a "standard" EP like this one. Still, the nearness of my eye to the main lens is not that bad and again, very pleased with this product. What's especially nice is that there is a removable Barlow element threaded in the inside of the chrome EP barrel. That element can be unscrewed - which then makes this a 8 mm EP. So you essentially get 2 EP's in one! I also purchased the 23 mm and it's outstanding! The specs say that the ER on this one is "9 mm", but I'd say it's more like 15 mm or more. It does make the viewing through it more comfortable. Love the big AFOV and very crisp images. Highly recommend both of these very good EP's as the next step up from any EP's you get bundled with a starter telescope and beyond!

23mm and 10m eyepieces team up well with SvBony SV501 70/420. Give wide bright views clear to the edges. Great value. Not so impressive with a 127Mak.

Fabrique un telescopio y compré el ocular de 23mm, llego en tiempo, bien empaquetado y muy contento con la compra

got it - works perfectly