<P> Telescopes at large observatories are typically located at sites selected for dark skies . They also increase the limiting magnitude by using long integration times on the detector, and by using image - processing techniques to increase the signal to noise ratio . The Keck Telescope, for example, 10 meters in diameter, can detect stars at 24 to 26th magnitude using a one - hour integration and adaptive optics techniques . </P> <P> Even higher limiting magnitudes can be achieved for telescopes above the Earth's atmosphere, such as the Hubble Space Telescope, where the sky brightness due to the atmosphere is not relevant . For orbital telescopes, the background sky brightness is set by the zodiacal light . The Hubble telescope can detect objects as faint as 31st magnitude, and the James Webb Space Telescope (operating in the infrared spectrum) is expected to have a magnitude limit of 34th magnitude . </P>

What magnitude can i see with my telescope