Sometimes I like to sit back and marvel at the remarkable progress our hobby has seen over the past half century or so. Technology has revolutionized everything, but perhaps nothing has changed more profoundly than astrophotography.

From 1949-1956, Palomar’s Samuel Oschin Telescope (then just called the 48-inch Schmidt) was used to conduct the first large-scale survey of the northern sky. The Palomar Sky Survey was the gold standard of such surveys for decades until it was surpassed by newer efforts like the Sloan Digital Sky Survey in the early 2000s. Many of these Palomar wide-angle pictures became the embodiment of what was possible with large professional telescopes. Astrophotographs like this seemed almost transcendent, a perception reinforced by the temple-like observatories atop distant mountains. This particular shot of M31 became the standard illustration used in hundreds of encyclopedias, textbooks, and popular science works of all kinds. I vividly remember this shot from our family’s 1968 Encyclopedia Britannica when I was a kid (look under “nebula,” not Andromeda).

The blinking animation shown here was created by alternating between the classic Palomar shot (black and white) and a color SeeStar S50 photo by MAS astrophotographer Carol Santulis. Carol’s is a 3.5 hour integration in mosaic mode processed in PixInsight. I couldn’t find the exposure details of the Palomar original but it always amazes me to see how far amateur astrophotography has come in about a human lifetime.

Consider this: despite being classified as a 48-inch (1.2 meter) telescope, the Oschin Schmidt telescope actually has a primary mirror that measures 72 inches (1.8 meters) in diameter due to its Schmidt optical design. The telescope tube is approximately 20 feet in length, and the optical tube and fork together weigh over 20 tons. In contrast, Carol’s SeeStar telescope has a 50mm objective (2 inches), 250mm focal length, operates on battery power, and weighs about 2.5 kilograms.

In just 75 years, you can carry the progress of astrophotography in one hand and witness its real-time results on your phone.

(Posted by John Rummel, August, 2025).