Final answer:
In optics, a negative magnification signifies an inverted image. Greatest angular magnification is achieved with a long focal length objective and a short focal length eyepiece. Lens quality and atmospheric conditions can affect observable details.
Step-by-step explanation:
The sign conventions for magnification in optics help in understanding the nature of the image formed by lenses and mirrors. If the magnification is negative, it signifies that the image is inverted relative to the object. This is important in various applications; for example, in telescopes, a negative magnification would indicate that the image formed is upside down. For the greatest angular magnification, which determines how large an object appears through an optical device like a telescope, a long focal length objective and a short focal length eyepiece are optimal. Lens quality and atmospheric conditions can limit the details observable despite the magnification achieved.