Posted by : wdkhan Saturday 7 September 2013


PHOTOGRAPHING THE STARS

High Apertures


High apertures are very important for this shooting condition since you will be photographing in the dark. A fast lens where it’s maximum aperture is f/2.8 or faster is recommended. To allow more starlight entering the lens from the darkness, a very high aperture setting is required. Lenses with maximum aperture of f/1.4 or f/2.0 are preferred. You could use f/2.8 lens, however you would have to increase the ISO sensitivity a little bit instead of decreasing the shutter speed.
f/1.4 or f/2.0 lenses are recommended , lenses with variable aperture such as f/3.5-5.6 are not recommended due to their low maximum aperture. Low maximum aperture will affect the shutter speed to be slowed down. However, it will require much higher ISO sensitivities than when used with f/2.8 lens. If you do not mind very grainy photographs, you can continue using f/4.0 lens but at very high ISO sensitivity.
Here is a helpful chart of NIKKOR & ZESSIS for the best useable high apertures that are free of chromatic aberration.
Note: Do not use glass filters now, use lens hood.

SLOW SHUTTER SPEEDS:

As expected, when photographing in very dark conditions, very slow shutter speeds are required. Choosing the best shutter speeds at the given aperture and ISO sensitivity could be tricky. The shutter speed must not be too fast or slow. Using too fast shutter speeds will result in underexposed photographs. Using too slow shutter speeds will result in over exposed photographs with small star streaks that are caused by the earth’s rotation (also known as mini star trails).
Choosing the shutter speed will require some experimentation; as long as it does not exceed 20s (seconds) shutter speeds. If using shutter speeds slower than 20’s it will result in small star streaks. It depends entirely on what aperture you set. It depends entirely on what aperture you set. For example, using a f/1.4 lens at f/2.0, it will require shorter shutter speeds. If using a f/2.8 lens at f/4.0, it will require long shutter speeds, however it is not recommended. We will discuss why in the next chapter.

Leave a Reply

Subscribe to Posts | Subscribe to Comments

Popular Post

MY STATS