1. The problem statement, all variables and given/known data An optical telescope has a diameter of 1.5m. It is placed at a site with 'seeing' of 1.0''. What is the expected resolution in arcseconds from observations made with the telescope at 1000nm? Give your answer to one decimal place 2. Relevant equations Theta (rads) = 1.22 * (wavelength/diametre of aperture) Rads * 180/pi = degrees 1 degree = 1*60*60 arcseconds 3. The attempt at a solution So far, I have used the equation: Theta = 1.22 * (wavelength / D) (where D = diametre of aperture). Thus using this equation I have worked out that: 1.22 * (1000 * 10-9 / 1.5) = 813.33 * 10-9 rads = 0.167 arcseconds. Where does seeing come into all this?? Its driving me mad!