Blitz or flash freely translated into the flash. This is one accessory that is widely used in the world of photography. Its main function is to Meng-Illuminate (expose / illuminated) the lack of light that objects exposed properly. But lately its use began expanding to produce artistic photographs. This article will discuss the basic knowledge needed to use the flash correctly.
Using the flash is not just a flash lit, turn the camera and then click the photo and be bright, but there are things we need to know in order to get a good photographic work.
Blitz and GN (Guide Number)
To divide / classify blitz, there are several classifications that can be used. The first, based on the availability of in-camera flash is divided into a built-in flash and external. Built-in flash from the camera itself while the external flash is flash additional connected using a cable or to the camera hot shoe. In addition, we can also divide it by the type / brand of camera.
We recognize dedicated and non-dedicated flash flash. Dedicated flash is a flash made specifically for the use of certain features within a specific camera. Normally camera manufacturers also issued a specific blitz for the line of the camera and can use features such as TTL, slow sync or rear sync, etc.. While non-dedicated flash has a very general functions of most cameras and can be used regardless of the type / brand of camera. This type of flash that usually require a lot of calculations for dedicated flash that has already received information from the camera lighting so it does not require additional settings again.
There are also flash output power (GN) can be arranged and some are not able to (fixed GN). We will likely talk more about the non-dedicated flash, non-TTL, and fixed GN.
In using flash photography, we will not be separated from the calculations related to the intensity of light reflected back from the object we cahayai. Therefore, we will meet with what is often called GN (Guide Number) or flash power. In short we can say that the flash powered, it can expose an object with more light and can reach more distant objects.
GN is basically a simple calculation power of flash. There are 2 kinds of writing notes by using a different calculation units are m (meter) and feet (ft). Normally in Indonesia we use the count with m. This is one of the considerations is also due to flash with the same strength, the number GN m and different feet away. In addition, the GN is generally written to use the film to ISO / ASA 100 and wide-angle (35mm/24mm/20mm).
GN is a product of the distance to the aperture (f / stop or aperture) on certain conditions (ISO / ASA 100/35mm/m or ISO / ASA 100/35mm/feet). For example, if we want to use the flash to photograph a person standing at a distance of 5m from us using a 35mm lens f/2.8, and we want to use flash then we need air-GN 14. Calculations used usually just looking for the right aperture for a particular blitz. For example, the flash GN 28 then to photograph the object is within 5m we will use f/5.6.
The notes are only a guide for the photographer. Not set in stone. Affecting a few. One is ISO / ASA used. Each increase of 1 stop on the ISO / ASA will cause GN increased by sqrt (2) or approximately 1.4 times (or farthest distance multiplied by 1.4) and 2 stop increase in ISO / ASA will cause the notes increased 2 times (or farthest distance multiplied by 2 ).
Blitz are almost always used in the room. The reason is because the lighting in the room is usually a little less bright light to produce images that can be seen. Indeed, there is a technique using a slow shutter speed to capture more light, but usually this causes image blur due to shake hands rather cameraman and the movement of people who want to take a picture. Therefore, we usually use a flash.
Its use is usually simple. We can set the digital camera on auto and let it do its job or it could be our own setting using a calculation that has been done above. It is not difficult. However, there are some things we need to consider in order to get maximum results.
1. Do not take pictures of objects that are too close to the face perpendicular blitz. Take for example the flash GN 20 which I think is quite adequate as an external flash for digital cameras in an indoor shooting indoors (not the hall). If we want to take people call it a distance of 2 meters with ISO / ASA 200 then we need f/16 are not available on most PDC and will produce images that are over. Therefore, for PDC / DSLR are usually built-in flash TTL and has a GN rather small (8-12 in some PDC, 12-14 on a DSLR). Use it instead of an external flash to the object rather close.
2. Combine flash with a slow shutter speed to get the main object tercahayai well and the background light source that has also caught well. It is a technique that should be tested and often produces beautiful images. Do not be afraid to use a low speed for existing objects are recorded flash will freeze (freeze).
3. If the room is a bit dark, be aware of the occurrence of red-eye / red eye effect. This red-eye occurs because pupils are dilated to familiarize yourself with the light a bit dark but suddenly startled a very bright light from the flash. If the camera and / or flash are pre-flash/red eye reduction facility, use it. If not, get around to change the angle of arrival to avoid direct flash light into the eyes.
4. In the room there was a strong light source such as a spotlight. Avoid looking directly into the picture with a strong light source is unless you want to get the silhouette is not perfect (compensation under 1-2 stop for a good silhouette). In such a case, use a flash to fill in / illuminates the object to be photographed.
Bounce / Diffuse
Flash is a very strong light source. In addition, the flash is the light that comes from the light source is small (narrow). Therefore, when a light is confronted directly on an object will cause harsh lighting (harsh). In most of the photo documentation of personal consumption where officers documentation using point & shoot camera (film / digital) can be accepted. But in the higher levels where the images will be general consumption, hard groove light will give effect to the less unsightly. Plus this usually will cause the light flash object that has been lightly whiten whites and cause specific details disappear.
There are several ways that we can do to avoid this in the sense that soften the light:
1. Expanding the field by reflecting the light coming into other fields (bounce).
2. Spreading the light coming from a small source is so widespread (diffuse).
Bounce flash is done by bouncing the flash to a broad field so that the light comes in a wider angle. We can use the ceiling or wall in the room. If the external flash mounted on a digital camera is connected via the hot shoe, the flash should have a tilt facility to reflect light. When attached via cable synchro, then we can put the flash on a bracket with a little face-up position / side or hold it in this position.
Reflect the proper position so that the light falling directly on the object is to confront the flash on the ceiling in the middle of the photographer / flash and the object.
Some things we need to consider in using bounce flash are:
1. Distance to calculate the f / stop turns not into the camera and the object distance but turned out to be the distance traversed by the light flash. Normally at a tilt angle of 45 ° we will widen the aperture 1 stop and the tilt angle of 90 ° we widen the aperture by 2 stops. Surely this is just a quick guide. Depending on the technical implementation in the field.
2. With regard to no. 1 above, then the distance langit-langit/dinding should not be too far or it will be useless.
3. Always use a white reflective areas and dark. Colors other than white will cause contamination photo colors while darker colors will absorb the light flash.
4. Note the possible emergence of a shadow on the other side of the light. For example, if we are bouncing into the ceiling then we will get the shadow under the nose or chin, and if we are bouncing into the wall on the left there will be a shadow on the right. To overcome this we can slip a bounce card on the front of the flash so that when we reflect the light to the top / side we still have a light that is not too strong a forward and neutralize shadow appears.
To take a picture vertically, it would be easier if we use a wired connection because we can easily exposes flash up when using a bracket or held. But if it is a hot shoe connections we make sure we have the facilities swivel flash head so that we can play facing up. Be great if we had a flash that can tilt and swivel. It will accommodate most of our needs.
Another way is to extend the softening light dispersion. How to use a flash diffuser. Flash diffuser will spread the light emitted from a flash in all directions so that the light that comes out is not hard. Generally available specifically for some flash diffuser considering different flash head. We can also make your own flash diffuser for us to use different tools.
When we use the diffuser, we actually hinder certain area from the direction of the light flash and turn it into another place. This reduces the power of the flash that we use. If the diffuser is the result that we use to buy, then we can read what we need aperture compensation when calculating exposure. Usually found on the box or paper manual. If we decide to make your own, then we could do the experiment many times in order to get the numbers right for the required compensation of the other times.
Overview if we think about the use of flash, then we’ll know if it applies to shooting a low light environment. Therefore, we generally do not think about the need to use flash in outdoor shooting (during the day, of course) because the sun was very bright. This is where we started error. Flash is required to shooting outdoors, especially on:
- The condition object to the sun. In this condition, the camera meter will think the atmosphere is bright enough so that it will cause the object to be photographed is dark / under strong light such as useless because it is not reflected by the object. How to outsmart is to do a fill-in on the object so that even if the background is very bright but the object still gets light.
- The sun is in the sky. This will result in shadows appearing on the bottom of the nose and chin. Use the flash to eliminate them. To soften the light using bounce card or diffuser.
- Objects that are in open shade (shadow). Flash is used to get the same lighting on the object as a whole will make gradation dark shadows of different objects on the parts especially the human face.
- The sky was blue and seductive. If we are not tempted by the blue sky and white sky willing to get photos when shooting outdoors it please do the metering on an object without using a flash or with flash. If we are willing to object as long as the lack of light blue sky please do the metering on the sky. Well, if we want the sky remained blue once the object tercahayai well, using metering on the sky and fill flash on the object. This will produce the right blend and fit.
- The sky is clouded over. When the sky was overcast, do not hesitate to use a flash because of the effects of clouds will be the same as if we were in the shadows.