SVBONY SV193 2" 0.8X Field Flattener for SV503 80mm F7 ED Telescope

This is a "must have" for the SVBONY SV503 80ED and the 70ED. On the 70ED telescope, it drops the focal ratio from f/6 to f/4.8 for a wider field of view and slightly brighter (faster) image. With the 70ED, I was able to get the entire Pleiades cluster on my ZWO ASI183MC Pro camera sensor with almost zero vignetting.

Not happy at all. You can definitely see the stars in all four corners look like eggs. When you look at a non cropped picture like my Christmas Tree star cluster and Cone Nebula shot you can see what I’m talking about. I do not recommend. I also had a sv503 that I purchased that the whole focuser just came loose during a session. I walked out to check on my rig and noticed that the camera was completely sideways. You could literally wobble the focuser back and forth. I purchased the ATO and reducer back in September and only got to use it a handful of times. I’d recommend maybe saving a couple bucks and purchase something of more reliable quality. When I contacted customer support. All they did was send me a couple of screenshots and an explanation of what a retaining thumbscrew was used for and after a couple of emails svbony dropped the ball on me. Not happy but lessons learned trying to save a couple of bucks.

The flatner works well when not adding anything between the flatner and the dslr camera. On a CCD you will need a 55mm space between the camera sensor and the flatner. DSLR camera already measure 55mm so just the flatner is the only thing needed. The flatner was made for small sensor like the one that comes with the ccd cameras so a little bit of egg shape stars might still form. You might need to process the stars with a lens distortion tool in adobe.

Me llego manchado. Nada que no se solucionara con una mi kit de limpieza de lentes, pero igual es algo raro para algo nuevo. Asumo error en el control de calidad del producto. De ahi en fuera funciona perfecto.

Excelente producto, cumple con las especificaciones del fabricante y solo depende a que clase de telescopio lo acople.

This is advertised as being for the SV503 but, with an additional spacer, it works well with my 550.

I received the field flattener at the end of November, and unfortunately it had two full thickness defects in the optical coating, about a mm in diameter each. They show up as the white spots near the periphery in the image, it's remarkably hard to take pictures of lens features. I contacted customer service the day I received the lens, both through Amazon and Svbony's site. Initially the Amazon email didn't respond, but Svbony's site email did, but only redirected me to the Amazon support site. This support did respond to a second email, and requested a few more images and then asked me to try to wipe off the defect with a soft cloth. After that they told me they'd send out a replacement. That was 2 weeks ago, and it's now been a month since I received the defective field flattener. I've sent two additional emails asking for updates that have both been ignored. I'm very disappointed in their customer service. Update - January 5, 2022 I received the replacement field flattener last night, about 5 weeks after starting the process. I debated docking 1 or 2 stars for the hassle, but decided on one star, because the flattener does seem to work well. I'll know for sure once the clouds clear out, but I'm glad to have a good piece of equipment to look forward to using now.

Complemento para el telescopio Svbony SV503 80mm, monto el aplanador de campo y me ayudó a enfocar los objetos de corta distancía al menos de unos 2Km. Espero complementar la información en los comentarios del telescopio propio ya haciendo pruebas de observación de espacio profundo. Pero excelente compra.

Excellent build, works as advertised on my f/7 telescope.

Will not be a clear picture new telescope ed frome sv503 came damaged. So no high expectations frome product and they seem.tk have no idea of new purchas. Left hangings hmmmm

Reductor focal y aplanador de campo. Elimina la coma en la periferia del campo visual y además ofrece reducción de la longitud focal en un factor de 0.8, lo que permite hacer exposiciones un poco mas cortas.

Does as described. Field is really flat paired with my ASI 533.