SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch)

This diagonal was a great upgrade compared to the diagonal that came with the telescope. The build quality is impressive. The price is incredible for the quality Much clearer image. Lots more light in the eyepiece Would buy again or recommend. So far the Svbony products I have purchased have all been top notch

Great clarity, value for money, very well made.

Exactly as advertised. Super fast shipping with Prime.

I have an orion 90mm telescope w/ equatorial mount, $130ish setup. Basic. This SV diagonal is an upright correct image. It has metal framework, and everything fits tightly. I feel more comfortable using this diagonal to hold my Barlow, filter, and eyepieces compared to what came with the telescope (combo plastic/metal). To me, the picture is somewhat of an improvement over what came with the telescope. I really just like the fitment! Oh, it didn't arrive broken!

Bought this as I have a small f/5 modified scope with limited infocus travel. My premium diagonals have a longer optical path length and don't work in this scope. This SVBONY diagonal has a shorter path and will allow my eyepieces to focus. This is pretty decently made, although my use is not optically demanding (low power only) the difference in reflectivity when compared to a non-dielectric diagonal can be seen. This diagonal is marked "99% dielectric coated" which refers to the mirror reflectivity. The side plates on this diagonal are blackened on the inside. SVBONY may have corrected the design or the ones mentioned that are red on the inside slipped past quality control, which is spotty with China manufacturing. Hopefully the coating on this is more durable than a conventionally aluminized mirror, since at this price point it's not worth reconditioning. The mirror appears to be glued in place, so if the collimation is off it's not really fixable. Check it with a laser collimator in the eyepiece port and place a flat mirror on the telescope side, facing the mirror and collimator. The laser spot should reflect dead center on the collimator target. This particular diagonal checked out fine, but since the mirror is likely installed by hand it should be checked when you get yours. IMPORTANT: there are similar SVBONY diagonals with silver side plates that are described as Dielectric. If they are, the specified reflectivity is VERY LOW for a dielectric mirror. Most likely it's incorrect information, and that's why they are about $10 cheaper. Getting a straight answer out of China makers is hard because of the language barrier. I think those have the same metal parts with a conventional non-dielectric mirror.

My first telescope only came with a 45 degree diagonal, this one is a nice upgrade. It seems solid and well made. The clarity and color are better than in the one that I had. Fit is nice and snug. The only complaint I have is really my own fault for not understanding the specs. This unit corrects the top/ bottom view, but not the left/right. Being a novice, this makes it a little more difficult for me to use. The price is very reasonable for what you get, but ultimately I will be looking to replace it at sometime because of the the left/right mirrored view.

Works great.. Had no problems with shipping and item arrived on time.

The SV188P seems perfectly good. As Svbony are Hong Kong–based, I’m comfortable the mirror is as described rather than the usual made-up marketing numbers. I contacted their support on a different matter and found them responsive and helpful. I don’t think the interior not being perfectly matte black is an issue, since there’s little to scatter, but it’s easily resolved anyway.

I didn't expect a 55$ diagonal to blow me away, but here we are. I recently purchased a Skywatcher 102mm StarTravel, the included 45 degree diagonal is perfectly usable for terrestrial, but for sky observing with objects high, it's much more of a problem. I was recommended this diagonal from a friend, and I was blown away with the difference in brightness and clarity of viewing. I have purchased a few SVbony products and they never fail to impress. This diagonal is no different. The mirror is huge compared to cheaper diagonals, and the dialectic coatings make it much brighter. If you need a diagonal buy this one with confidence. It comes with a brass band and not just a screw, so your eyepieces shouldn't get scratched up. Getting used to left and right being backwards, takes some getting used to, but it's definitely not a deal breaker. An unexpected side benefit, is the mirror is very easy to clean. (with a microfiber cloth) That was a problem with the default one that came with the scope.

Produto original, a qualidade do material é excelente, amei

This product gives full value for the money.It is a part of the telescope which can really make a difference,especially if the one being replaced is stock ,which came with the telescope.

Cumple con lo ofrecido y es una mejora a la diagonal que me vino con el telescopio, se percibe mucha calidad en la construcción del producto al ser completamente de metal.

I've generally been happy with the various SVBONY items I have purchased. This diagonal seems well made, and does seem a bit brighter than older diagonals I have.