The 77mm Mirror Filter from Kase features an opaque, nonreflective black circle sandwiched between two sheets of B270 optical glass to create an unusual effect filter. The black circle does not read in the image but combines a slight, soft defocus effect paired with halo-shaped highlights from light points in the image area. The halo shape's effect varies with the aperture, allowing the impressionistic effect to be adjusted.

The placement of the opaque black circle may cause some autofocus systems to not fully function, but by recomposing the shot and holding the focus point, the shot may still be taken. The circle is fully protected by glass on both sides and will not scratch off or otherwise wear away.

Rear-Threaded Soft Defocus Filter    Creates Halo Bokeh Effect    Multicoated B270 Optical Glass

Related Questions and Answers

Q: 1. Is there a T mount adapter for this Opteka mirror lens that will fit an L mount FF camera?

A: Yes, there are T-mount adapters to adapt the Opteka 500mm f/6.3 Mirror Lens for T Mount to the L-mount. Currently we have the Leica T2 Digiscoping Adapter, BH #LEDAT2T (https://bhpho.to/3P0XHuW).

Q: 2. Does this lens have any noticeable comatic aberration?

A: We have not heard of any noticeable chromatic aberration with this lens to date.

Q: 3. Is the T-mount included? Is there a hood that will fit?

A: T mount not included, but its inexpensive. And you can get the proper one for your camera.No hood that I know of...

Q: 4. Good night: Will this Opteka 500mm f6.3 95mm mirror lens fit my Sony A390? I need T2 thread for Sony @390 DSLR camera (A390).

A: To use the Opteka 500mm f/6.3 Mirror Lens for T Mount on the Sony Alpha A390 Digital SLR Camera, you need the Vello T Mount Lens to Sony A-Mount Camera Adapter. Here is the link: https://bhpho.to/3lUBHao.

Q: 5. Does this lens produce a ring/donut bokeh?

A: Yes

Q: 6. What is the difference between this and the Bower 500 mm f/6.3 mirror lens that costs $199? They look like they come from the same factory.

A: The Opteka 500mm f/6.3 Mirror Lens for T Mount and the Bower 500mm f/6.3 Manual Focus Telephoto T-Mount Lens are very similar in design. There are a couple differences. The Opteka is currently made in China, whereas the Bower is currently made in South Korea. The Opteka comes with a Limited 10-Year Warranty, whereas the Bower comes with a Limited 1-Year Warranty

Q: 7. The Diagonal (2") has 2"-18 threads; will it fit the rear cell of the Celestron 8" evolution OTA which has a thread spec of 2"-24?

A: Yes, the Celestron 90-Degree Mirror Diagonal (2") for SCT Scopes will fit the rear threads of the Celestron NexStar Evolution 8 203mm f/10 Schmidt-Cassegrain GoTo Telescope.

Q: 8. will this lens work with and Olympus OM or a Pentax K1000? If an adapter is required, will two different ones be needed or just one?

A: You would need T-mount to any camera adapter (T-mount to Olympus OM , T-mount to Pentax K )

Q: 9. Will it fit a canon AE-1 35mm film camera?

A: Opteka 500mm f/6.3 Mirror Lens for T Mount is compatible with the Canon AE1 but you also need to get this FD to T mount adapter. https://www.bhphotovideo.com/c/product/116734-REG/General_Brand_ATC_T_Mount_SLR_Camera_Adapter.html

Q: 10. Work on a D5000 nikon?

A: You may purchase the Vello T-Mount Lens to Nikon F-Mount Camera Lens Adapter, B&H # VELANFT, to connect the Opteka 500mm f/8 HD Telephoto Mirror Lens for T Mount to the Nikon D5000 DSLR camera. Do note that the Opteka 500mm f/8 HD Telephoto Mirror Lens for T Mount is a fully manual lens, and as such, you will have to place the camera in full manual mode and set your exposure manually to use the above lens. The camera's shutter will not release if the camera is not set to full Manual mode.