When and How to create long exposure photography
Many photographers are somehow afraid of using long exposures. As you’ll learn in today’s topic, there is absolutely nothing to worry about - just the opposite! If you use your knowledge in right way, your photos substantially improve.
If we speak about long exposures it may usually mean two basic things: At first long exposures from relative point of view and at second, long exposures from time point of view. We’ll start with first one, because they are more simple.
Long exposures from relative point of view means, that user of digital camera decides to prefer longer exposure than value recommended by CPU. Let’s say, we photograph family standing near waterfall, it is possible to rely on recommendation of automatic mode, however, you probably end with water reminding ice or sculpture – times slower than 1/100 s make water actually look more and more “frozen” and look unnaturally.
On the other side, if you decide to use slightly longer exposures, you may make your waterfall really look like moving water. Simply set exposure under 1/100 s (let’s say 1/50 s or 1/75 s should do) and shoot photo.
Now your water will be nicely smeared and look truly better. Use this trick anytime you think it bring better looking photos – emphasis on moving F1 car, with “action” photo from ice hockey etc.
Shooting long exposure photography
Long exposures from time point of view stands for exposures, which are used directly, because there is no other way, how to take this photo. Good example is starry sky – automatic mode wouldn’t be able to do anything with it. Even if you set “Stars” scenery mode, it is far better to choose “Shutter Priority” or “Full Manual”.
When shooting with long exposures, you have to first decide, if movement is your friend or your enemy. First case may be applicable for situations in which you for example photograph night highway or fireworks and you want to enforce long lines from colored lights. Other case is when you want perfect photo without any movement in it.
This is above mentioned situation with shooting of stars, moon and simply all dark scenes where "Aut"o do not suffice. In all of these cases you must ensure 2 things: No movement on scene (watch out for birds, falling snowflakes etc. - btw. stars with longer exposures looks like short lines!) and no movement of camera.
Expositions under cca 1/20 s – 1/40 s on typical 38 mm objective absolutely must be stationed on tripod (do not forget to turn off stabilization in such a occasion!). Which model of tripod to choose is not objective of current article, however we recommend to select type which is high enough – photographs from 120 cm tripod is not very natural for our human eye.
Unluckily, while shooting long exposures you have to fight much often with noise. As usually, the higher ISO you set, the more noise you could expect. With higher end cameras you may shoot into RAW and try to reduce it on PC. If you own just simple compact, you’ll probably end with predefined value or (in better cases) with setting of effectiveness of noise reduction algorithm.
Reducing noise brings another dilemma - good techniques with noise also wash out actual drawing, but you may use high ISO, less effective techniques save painting, however they are usable only on lesser ISO values.
