STF 1768 (25CVn) is a binary system located 198 light-years away. The primary component is a giant star of spectral type A7III, with a mass of 2.23 times that of the Sun, and the companion is a main sequence star of spectral type A8V, with a mass of 1.58 times that of the Sun. The orbital period of the components is approximately 245 years.

103mm - 25CVn is quite a challenge for a 4" refractor. The magnitude difference between the components is 2 magnitudes, and with a separation of just about 1.7", it can be quite tricky at this aperture. I initially observed this binary star under average to poor conditions at 159x. There was a slight breeze, which didn’t help with the seeing. It was clear that the seeing wasn’t very good, but despite that, I could see the position of the companion as a brightening on the diffraction ring. However, this could not be considered a successful observation. I took a break and pointed the telescope at the globular cluster M3. While observing it, I didn't even realize how much time had passed, and nearly an hour had gone by. 25CVn had climbed a bit higher, and the conditions were much better this time. After refocusing at 159x, the companion appeared as a small gray disk, clearly separated by a gap from the primary component, which I observed as white. I increased the magnification to 198x, and here the binary star showed its full beauty. After a while, the seeing began to deteriorate again, and the companion started to fade in and out of view. I consider the resolution of this binary star with the 103mm refractor to be a successful observation.