How to choose a flash that suits you?

As we know, flash is one of the important equipment for portrait photography, and its importance is second only to cameras and lenses. It can be said that portrait photography can be done without tripod but without flash. It's normal for a good portrait photographer to have four or five flashlights.

So how should we choose the flash? The first is to choose flash by brand. For example, Canon cameras should choose Canon flash, and Canon cameras cannot use Nikon flash. In addition, you can also choose a secondary factory flash. Since 2008, domestic flashlights have mushroomed, which has undergone a fundamental change compared with the previous' Yin Yan' flashlights. Although there is still a considerable gap compared with the original flash, the price of 1/4, 1/5 or even lower is quite attractive. Of course, these are not the focus of today. Let me talk about an important indicator of flash memory-flash memory index.

Flash index is a data value reflecting the output power of flash, which is usually expressed by GN. It is based on the setting of ISO 100 sensitivity film or digital camera. A good flash should have a stable and adjustable output and a standard color temperature (generally about 5500k, just like sunlight). For example, a bunch of formulas are the product of the film era and are out of date. In the digital age, shooting has become very intuitive, and we can make progress by discarding unnecessary things.

Remember a data GN-26 (flash index 26). This refers to the basic flash index required for the flash to shine directly on the model when shooting portraits. It should be noted that direct flash is a product of the film age. Now we all use digital cameras to suggest shooting in a' jump flash' way as much as possible. If you take a portrait directly with a digital camera, it will make people feel that you are very low-end (except for shed shooting, group shooting and outdoor portrait). So what is' jumping flash'? Lift the lamp head of the flash lamp upward, strike the light on the roof or the surrounding walls, and illuminate the main body by using the principle of diffuse reflection. In order to obtain a more natural or soft fill light, this flash mode is called' jumping flash'.

Ok, I just said that the index GN-26 is the basic index for direct shooting, so is the flash method enough? Yes, it's a little small. Imagine that the flash hits the ceiling and then reflects on the model, which is equivalent to 2/26= 13, and the flash index that really acts on the model is only 13. Therefore, we should take the exponent x 2 of the flashlight, that is, 26 x 2 = 52 (gn). Remember to buy flashlights with an index greater than GN-52 as much as possible. There are many kinds of flashlights, such as Canon EX-580II, Nikon SB-800, and a large number of vice-factory flashlights, such as' Yongnuo', with a flash index above GN-55. There is already a flash with a small index, such as Canon EX-430, index 43, Nikon SB-900, index 34, and the indexes are all smaller than GN-52. What should I do?

No problem, you just need to adjust the sensitivity.