![]() ![]() If you are going to photograph star trails, then it is vitally important (and anti-intuitive) to TURN OFF ‘Long Exposure Noise Reduction’. I would also opt for shorter exposures where there was a lot of air traffic, thankfully, in Africa this is another factor we rarely have to consider! If I was somewhere busy (for example the Quivertree forest in Keetmanshoop, I might opt for shorter exposures). Admittedly, I tend to photograph stars in exceptionally remote locations. I find this helps to create smooth wheels while mitigating the risk of light pollution. I expose my image stacks for 4 minutes at a time. My preferred method sits somewhere in the middle. In a stack of up to 300 shots, you may be able to afford a few damaged ones. With stacked images, you have a degree of safety because you can simply discard the ruined frames. I use a little wireless one made by Hahnel. Make sure it is the right kind for your brand of camera. Canon 7D mark ii - limited to 30 second exposures), however, if yours doesn't then pick up a cheap one from your local camera supplier. Many cameras now have them built in (e.g. In both cases you are going to need a method to hold your shutter open. For example, you might be two hours into your single exposure shot when suddenly a lone car drives by, or someone flashes you with a powerful torch.High risk! Longer exposures create beautifully smooth wheels but they are at significant risk of additional noise and worse, inadvertent or accidental light pollution. December solstice to March equinox: 89.There are pros and cons for both of these methods, as one would expect, nothing is ever cut and dried in photography!.September equinox to December solstice: 89.8 days.June solstice to September equinox: 93.6 days. ![]() March equinox to June solstice: 92.8 days.On average, spring lasts for 92.8 days in the Northern Hemisphere and 89.8 days in the Southern Hemisphere. The Earth does not move at a constant speed in its elliptical (oval) orbit, so the seasons are not of equal length. September | October | November | December How Long Is Spring? ![]() March | April | May | June Southern spring months Read more about the history and meaning of the spring months: Northern spring months South of the equator, it starts in September and ends in December. In the Northern Hemisphere, depending on which definition you use, spring can include parts or all of the months of March, April, May, and June. The start of spring and the spring equinox are celebrated in cultures and religions around the world with various spring traditions, holidays, and festivals.Įaster, New Year, and the “other shore”: spring festivals of the world Spring Months Particularly in the temperate zone, which is the region between the tropics and the polar regions, spring is also the time when the cold of winter begins to give way to warmer weather, though this varies substantially from one region to another.Ĭlimate and monthly average temperatures in your city Traditions and Folklore Other astronomical terms & definitions Rising Temperatures It falls a few days before the spring equinox and some days after the fall equinox in both hemispheres. The date when day and night are actually equal is called the equilux. In most regions, daytime at the equinox is a bit longer than 12 hours. The name of the event derives from Latin and means equal night, giving the impression that both day and night are exactly 12 hours long. Our Earth is tilted as it orbits the Sun, which is the reason we have seasons on Earth.Īstronomical spring begins on the day of the equinox. In Toronto, the day of the spring equinox is 3 minutes longer than the previous day in Miami, roughly 2000 kilometers or 1200 miles farther south, the difference is only about 1 minute and 31 seconds. On the longest day of the year, the summer solstice, the day-to-day difference reaches zero.Īt the same time, locations farther from the equator experience larger day-to-day differences. After that, days still get longer, but at an ever-decreasing rate. In fact, the increase is greatest in the days surrounding the spring equinox. Meteorological and other seasons definitions Greatest Increase in Day LengthĪs spring starts, the length of day increases dramatically in most regions-except for the tropics, where day lengths do not change much during the course of a year. Also, some countries don't have fixed season dates but determine the start and end of spring based on average temperatures. In meteorology, the spring season begins on a different date. ![]()
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