Traditional Culture Encyclopedia - Photography and portraiture - The difference between light spots and bright spots

The difference between light spots and bright spots

Light spots

The bright tissue that appears at the edge of the solar photosphere and extends outward to the chromosphere is the spectral spot. Spots of light generally surround and are closely related to sunspots.

The spots related to sunspots are composed of bright fibers, 5,000-10,000 kilometers wide and about 50,000 kilometers long. They are roughly perpendicular to the equator; the spots unrelated to sunspots appear in high latitudes of 70°. It is small in area, slightly circular in shape, with a diameter of about 2,300 kilometers, and an average lifespan of only half an hour. The light spots appear hours or days earlier than the sunspots, and after they appear, they gather into two parts, showing dipole characteristics similar to the sunspot groups. The sun's differential rotation gradually pulls the initially circular spot into an ellipse, with its leading part slightly closer to the equator. The spots break down into many small pieces at the end of development and then gradually disintegrate.

The light spot has the same 11-year activity cycle as the sunspot, but the latitude activity range of the light spot is about 15° wider than that of the sunspot.

The spectrum of the light spot shows that its ion spectrum lines are stronger than the photosphere, while the neutral atom spectrum lines are weaker than the photosphere, so the temperature of the light spot is higher than that of the photosphere. However, the ratio of the total radiation intensity of the light spot to the photosphere changes with the distance from the heliocentre, which shows that the light spot is not in radiation equilibrium, with a lower temperature at the bottom and a higher temperature at the upper level. What is seen near the edge of the sun is the upper layer of the light spot. Its average temperature is about 100 degrees higher than the surroundings, and its brightness is about 10% greater.

The magnetic field of the light spot is mainly longitudinal, with an intensity of hundreds of Gauss.

Flare

flare

A photographic lens composed of several lenses. When light passes through the lens, it produces harmful reflections that obscure the picture. This is called a flare. Therefore, the coating of the photographic lens also plays a role in preventing light spots. Especially when shooting with backlight, it is easy to produce light spots if the lens hood is not installed.