In 1957 John applied the concept of the Maksutov meniscus camera to the Cassegrain telescope, making possible the compact design and sharp, well corrected images of the Questars, Quantums and other "Maksutovs" of today's commercial telescope industry.
Now commonly refered to as the "Maksutov" telescope, it was John that actually designed the first f/23 system of this type for visual use which he later refined to make f/15 systems possible.
By the 1970's Celestron had introduced the low-cost and roughly similar C-90 telescope and telephoto lens, and by the 1990's Meade Instruments was producing "Maksutov" telescopes in the 4-inch and 9-inch aperture range.
The pictured telescope is a masterpiece of the telescope maker's art that John built and brought to the Texas Star Party in 1984. These photos only hint at the forethought and clever design that went into this prime specimen. Both setting circles are illuminated and viewed through an eyepiece built into the north end of the polar axis.
The telescope's focuser is fitted with a rotary eyepiece holder that serves both the finder and the main telescope.
Since few have heard of the Gregory Meniscus Telescope by other than the Maksutov name,
I thought I would write this little note to give credit to whom credit is due.
As a postscript, in 2005 I received e-mails from a fellow at McDonnell observatory in Texas, informing me that this telescope now resides there. The McDonnell observatory visitor centor website also mentions: "...utilized in the telescope park along with an exquisite 8" fixed eyepiece scope designed, built, and donated by Mr. John Gregory."
- Jim Sapp