The resolving power of a refracting telescope increases with the diameter of the spherical objective lens. In reality, it is impractical to increase the diameter of the objective lens beyond approximately 1 m. Why? a. The resultant sagging of the mirror will cause spherical aberration. b. If the objective lens is too large, it is difficult to keep it clean. c. The spherical objective lens should be replaced by a paraboloidal objective lens beyond a 1-m diameter. d. The increasing size of the objective lens will cause chromatic aberration to grow worse than spherical aberration. e. The resulting increase in light scattering from the surface of the objective lens will blur the image.

The resolving power of a refracting telescope increases with the diameter of the spherical objective lens. In reality, it is impractical to increase the diameter of the objective lens beyond approximately 1 m. Why? a. The resultant sagging of the mirror will cause spherical aberration. b. If the objective lens is too large, it is difficult to keep it clean. c. The spherical objective lens should be replaced by a paraboloidal objective lens beyond a 1-m diameter. d. The increasing size of the objective lens will cause chromatic aberration to grow worse than spherical aberration. e. The resulting increase in light scattering from the surface of the objective lens will blur the image.

	a.	The resultant sagging of the mirror will cause spherical aberration.
	b.	If the objective lens is too large, it is difficult to keep it clean.
	c.	The spherical objective lens should be replaced by a paraboloidal objective lens beyond a 1-m diameter.
	d.	The increasing size of the objective lens will cause chromatic aberration to grow worse than spherical aberration.
	e.	The resulting increase in light scattering from the surface of the objective lens will blur the image.