Which is better, the AstraZeneca Refractive Astronomical Telescope (300 mm caliber) or the APO Refractive Telescope (150 mm caliber) for imaging or starry sky shooting?

The comparability between the two is very poor.

The former (C 12) is a telephoto Zeca, and its strengths lie in telephoto and high-resolution planetary surface observation, binary star observation and small-scale celestial observation in deep space. In the field of photography, its strengths are similar to those mentioned above. Its focal length is 3000mm, even with a defocusing lens of 0.6, it can reach 1.8 m, far exceeding the focal length of 150APO (not exceeding 1 m). Therefore, the shooting targets of the two are basically not comparable.

I'm not sure whether C 12 has an optional F/2 camera system, but even if it does, it will be very expensive.

APO's strength lies in shooting deep space celestial bodies with large field of view, and it is also suitable for high, medium and low power visual inspection of various celestial bodies. Its image quality is bright and beautiful with large contrast, far exceeding 300 Zeca in terms of appreciation, but its absolute resolution will be lower than 300 Zeca due to the aperture.

Therefore, it is best not to let these two players who are not at the same level and are in the same event stand on the same starting line. Liu Xiang and Nie Weiping race, the victory is not martial; Tai Sen and Xu Haifeng fought. If Xu Haifeng didn't have a gun, he would die. It is best to determine your main purpose first, and then choose accordingly. The most suitable mirror is the best mirror.