--- product_id: 387957015 title: "SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch)" brand: "svbony" price: "3009715β‚«" currency: VND in_stock: true reviews_count: 5 category: "Svbony" url: https://www.desertcart.vn/products/387957015-svbony-sv188p-dielectric-mirror-star-diagonal-90-degree-mirror-diagonal store_origin: VN region: Vietnam --- # 99% Reflectivity Dielectric Coatings 90Β° Viewing Angle for Comfort Brass Compression Rings for Secure Fit SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch) **Brand:** svbony **Price:** 3009715β‚« **Availability:** βœ… In Stock ## Summary > πŸ”­ Elevate your stargazing game with crystal-clear brilliance and unmatched comfort! ## Quick Answers - **What is this?** SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch) by svbony - **How much does it cost?** 3009715β‚« with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.vn](https://www.desertcart.vn/products/387957015-svbony-sv188p-dielectric-mirror-star-diagonal-90-degree-mirror-diagonal) ## Best For - svbony enthusiasts ## Why This Product - Trusted svbony brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Secure & Scratch-Free:** Built-in brass compression ring locks eyepieces firmly without damaging barrels during adjustments. - β€’ **Effortless Maintenance:** Mirror surface is easy to clean with a microfiber cloth, keeping your view pristine night after night. - β€’ **Comfort Meets Precision:** 90-degree diagonal angle ensures effortless, strain-free viewing of celestial objects overhead. - β€’ **Universal Compatibility:** Fits all standard 1.25-inch telescopes and accessories, including filters and Barlow lenses. - β€’ **Brilliant Clarity, Every Time:** Super flat dielectric mirror reduces light loss for ultra-bright, crisp astronomical views. ## Overview The SVBONY SV188P Star Diagonal features a super flat dielectric mirror with over 99% reflectivity, delivering brighter and clearer astronomical views. Its 90-degree angle provides comfortable viewing, while the brass compression ring ensures a secure, scratch-free fit for all standard 1.25-inch telescope accessories. Lightweight and easy to maintain, this diagonal is a top-tier upgrade for serious sky observers. ## Description SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings Review: 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. Review: Produto original, a qualidade do material Γ© excelente, amei ## Features - Dielectric coatings; super flat mirror with dielectric coatings to reduce reflected light loss; provide an over 99% reflective surface; good for astronomical viewing - 1.25 inches nosepiece fits 1.25 inches telescopes; accepts standard 1.25in filters; eyepieces; Barlow lenses and other accessories with a 1.25in insert barrel - 90 degree viewing angle; diagonal reflects the telescope’s light path 90 degree to provide a more comfortable viewing angle; best for observing objects overhead - Correct upside down and left right reversed image; the view image is upright; but left and right reversed if use the 90 degrees to your telescope - Brass compression ring; Built in brass ring and thumbscrew accessories avoid eyepiece to rotate during adjustments; effortless fixes more firmly and will not scratch your eyepieces barrels ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B08QRY4V97 | | Additional Features | Dielectric coatings for reduced light loss and 90-degree viewing angle | | Best Sellers Rank | #76,120 in Electronics ( See Top 100 in Electronics ) #2 in Telescope Diagonals | | Brand | SVBONY | | Built-In Media | 1X SVBONY SV188P Dielectric Mirror Star Diagonal | | Compatible Devices | Eyepieces, Filters | | Customer Reviews | 4.8 out of 5 stars 299 Reviews | | Finderscope | no | | Focus Type | Fixed Focus | | Focus type | Fixed Focus | | Item Dimensions D x W x H | 11.2D x 6.1W x 8.4H centimeters | | Item Weight | 0.2 Kilograms | | Manufacturer | SVBONY | | Manufacturer Part Number | FCAF9171B | | Model Name | FF9171B | | Model Number | FF9171B | | Model name | FF9171B | | Objective Lens Diameter | 31.75 Millimeters | | Objective lens diameter | 31.75 Millimeters | | Product dimensions | 11.2D x 6.1W x 8.4H centimeters | | Unit Count | 1 Count | ## Product Details - **Brand:** SVBONY - **Focus type:** Fixed Focus - **Model name:** FF9171B - **Objective lens diameter:** 31.75 Millimeters - **Product dimensions:** 11.2D x 6.1W x 8.4H centimeters ## Images ![SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch) - Image 1](https://m.media-amazon.com/images/I/71imU2LlM+L.jpg) ![SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch) - Image 2](https://m.media-amazon.com/images/I/71Ij1EICEWL.jpg) ![SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch) - Image 3](https://m.media-amazon.com/images/I/817zmNBbyaL.jpg) ![SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch) - Image 4](https://m.media-amazon.com/images/I/81uzZXKOyUL.jpg) ![SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch) - Image 5](https://m.media-amazon.com/images/I/71lDyEQ2Y3L.jpg) ## Available Options This product comes in different **Size** options. ## Questions & Answers **Q: Will this fit into the svbony guide scope? the svbony guide scope is reflected and i would like to have the image flipped upright.** A: thanks for your question, for SV188P dielectric mirror star diagonal, it can only fit with SV198 Guide scope. here is the link: https://www.amazon.com/dp/B09C8913FZ?ref=myi_title_dp If any, please contact us through Amazon message. **Q: Svbony, is this diagonal actually painted red on the inside as some buyers indicated?** A: Unless there are two versions of this diagonal just know that the side panels ARE red on the outside AND inside. As some buyers report this could cause a reddish reflection that might cast a red hue onto what is being viewed, particularly brighter objects I would guess. Due to cloudiness, I haven't been able to test that possibility yet. Otherwise it's a nice 99% diagonal. **Q: Does this diagonal have a stop to keep a standard size Barlow tube from colliding with the mirror?** A: thanks for the question. For the SVBONY SV188P Dielectric Mirror Star Diagonal, there is no blocking thing, the end where the eyepiece or accessories are installed, there is about 45mm long installation space in the inner section, don't worry about touching the lens. **Q: "when use the sv188p with maksutov-cassegrain (mak-cass) or schmidt-cassegrain telescope, you need a special adapter." what is the needed adapter?** A: thanks for your question. If your telescope has a two-inch interface, you may need a 2-inch to 1.25-inch adapter ring. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Review *by D***N on 21 December 2023* 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. ### ⭐⭐⭐⭐⭐ Review *by 1***2 on 4 April 2026* Produto original, a qualidade do material Γ© excelente, amei ### ⭐⭐⭐⭐⭐ Review *by R***Y on 27 December 2025* 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. ## Frequently Bought Together - SVBONY SV188P Dielectric Mirror Star Diagonal, 90 Degree Mirror Diagonal, 99% Reflectivity Dielectric Coatings with Brass Compression Rings (1.25 inch) - SVBONY SV135 Zoom Eyepiece, Zoom 7 to 21mm 1.25 Inch Telescope Eyepiece, 6 Element 4 Group Telescope Accessories for Astronomic Telescopes Visual - SVBONY Barlow Lens 2X, 1.25 inch Barlow Lens with Multi Coated Broadband Green Film, Telescope Accessories with M42 Thread for Telescope Eyepiece --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.vn/products/387957015-svbony-sv188p-dielectric-mirror-star-diagonal-90-degree-mirror-diagonal](https://www.desertcart.vn/products/387957015-svbony-sv188p-dielectric-mirror-star-diagonal-90-degree-mirror-diagonal) --- *Product available on Desertcart Vietnam* *Store origin: VN* *Last updated: 2026-05-21*