Diameter 114 mm Focal Length 900mm Newtonian Reflector Mirror for Astronomical

Perfect for a fun project telescope. I bought 3 of these sets, one for my Dad, one for my youngest son, and one for myself. We used them in 114mm Hadley telescopes that we 3D printed the majority of the parts for. We have really enjoyed the views that these inexpensive mirrors have provided of the moon, and our planetary neighbors.

I had a bad experience with a different amazon seller- the ronchi test showed severe zones in the sphere, some of the worst I've ever seen. This mirror is great, with only slight undercorrection and some TDE at the edge- this is time consuming to remove and largely doesn't affect the view, and can easily be masked. In some cases, like this one, it may even be beneficial to have a slight bit of TDE (but it gets complicated). Overall this is a great buy for 30 dollars. Attached is my outside ROC ronchi test of this mirror, Blue, and a perfect ronchi test, black and white. You can be confident in this purchase.

I rebuilt an almost free goodwill reflector telescope using these mirrors. They were a perfect fit and an inexpensive way to bring a telescope back into service.

The mirrors showed up perfect and worked great on my diy telescope, I even ordered a second set!

Both mirrors are in good shape.

My set was missing the smaller mirror. The only option is to return the larger mirror but I already have installed it. The seller reached out to me after my negative review and sent me a replacement. Both mirrors are in perfect condition and the seller was responsive so I'm giving them 5 stars.

Used for a Hadley Telescope, worked very nicely. Very nicely packed and inexpensive.

I bought this after getting a very unsatisfactory mirror set from a different seller. This mirror, however, is excellent! The mirror has no visual abnormalities, and provides very clear images at all magnification levels tried. I highly recommend it of you're looking to build your first telescope, especially one of the Hadley design. The attached photo, taken on a cellphone through a 15mm eyepiece, doesn't do the live view justice but gives you a vague idea of what to expect. You won't be disappointed.

Worth it to buy

Ótima qualidade. Produto excelente

I purchased two. Received two boxes. But, secondary mirror is not there in any of the two mirrors.

反射鏡の精度は判りません DIYで鏡を交換して遊んでいます。 月は綺麗に見えました それ以上は工作精度とか絡んでくるので DIYでは判断が付きません ただ、海外便なので 納期が書いてあるより長いですよ〜〜 ドキドキしました。 リサイクルで F５００の望遠鏡を４０００円で買い 鏡が駄目なので 買い求めましたが ５００ミリが見当たらず 鏡筒を付け足して ９００ミリが使えるようにしました

Works well