{"id":1213,"date":"2016-07-14T19:52:47","date_gmt":"2016-07-14T19:52:47","guid":{"rendered":"http:\/\/www.kenkoskela.com\/blog\/?p=1213"},"modified":"2016-07-14T19:52:47","modified_gmt":"2016-07-14T19:52:47","slug":"how-to-expose-for-flash-and-existing-light-separately-using-your-cameras-controls","status":"publish","type":"post","link":"https:\/\/www.kenkoskela.com\/blog\/how-to-expose-for-flash-and-existing-light-separately-using-your-cameras-controls\/","title":{"rendered":"How to Expose for Flash and Existing Light Separately Using Your Camera\u2019s Controls"},"content":{"rendered":"
\"asia,asian,bali,east<\/a>
<\/p>\n

Indonesian Girl at Sunrise<\/a> : Prints Available<\/a><\/p>\n

Beautiful girl carrying a pot of water on a beach at sunrise<\/p>\n

<\/figcaption><\/figure>\n

Flash photography can be intimidating. Adding artificial light to the existing light in a scene and getting a proper balance between the two requires some basic knowledge and skill on the part of the photographer. If you are not yet experienced using flash, but have an interest in giving it a try, an important first step is understanding how to control exposure of the light from your flash and the existing light (a.k.a. ambient light) separately using your camera\u2019s and flash\u2019s controls. <\/p>\n

You probably already have a good understanding of how to control shutter speed, aperture and ISO to arrive at a proper exposure when flash is not being used. Let\u2019s look at how these three variables, as well as your flash\u2019s output, come into play when you are adding artificial lighting to the scene.<\/p>\n

Introducing Leon the Lion<\/strong><\/p>\n

It\u2019s been awhile since I\u2019ve been on safari and I\u2019m missing it. So I thought I\u2019d borrow Leon the Lion from my daughter\u2019s room and pretend I was back in Africa. My settings here were ISO 400, 1\/50th second and f\/8. I shot in manual mode. No flash yet.<\/p>\n

\"1<\/a><\/p>\n

Next, I added the off-camera flash. I used manual mode on my flash and fired it through a small soft box at 1\/32nd power. The image below is our starting point for an exercise to learn how your camera and flash controls affect how much flash and ambient lighting end up in your image.<\/p>\n

\"2<\/a><\/p>\n

Shutter Speed<\/strong><\/p>\n

Changing your shutter speed won\u2019t affect the amount of flash lighting that ends up in your image. This might be surprising to you, but it makes perfect sense. Here is why:<\/p>\n

The flash has to fire while the shutter is open. Your camera will have a \u201cmaximum sync speed\u201d, which is the fastest shutter speed whereby that can be accomplished. Usually this is around 1\/200 of a second (I\u2019m ignoring \u201chigh speed sync\u201d for now). Even at full power, the blast of flash happens faster than your maximum sync speed. So, the same amount of flash will illuminate Leon when we reduce the shutter from 1\/50th to 1\/100th second. Here is the image after the shutter speed change.<\/p>\n

\"3<\/a><\/p>\n

Notice that the flash lighting on Leon appears mostly the same as with the original settings, even with the adjusted shutter speed. However, the background has gotten darker. So, using shutter speed, we\u2019ve just controlled the ambient light background separately from the flash-lit subject. There was some ambient light hitting the subject, in addition to the flash, so we don\u2019t have complete control over the separate light sources. But you can see that we have considerable control here.<\/p>\n

Aperture<\/strong><\/p>\n

Now, let\u2019s reset our settings back to ISO 400, 1\/50, f\/8 and 1\/32nd flash power. This time, let\u2019s adjust only the aperture. Staying with this idea of cutting the light in half, let\u2019s adjust the aperture by 1 stop from f\/8 to f\/11.<\/p>\n

\"4<\/a><\/p>\n

Notice that both the flash lighting on Leon and the background lighting went darker than with the original settings. So, the aperture controls both the amount of flash lighting and existing lighting in the image. But wait… there\u2019s more to say about aperture….<\/p>\n

Shutter Speed and Aperture Together<\/strong><\/p>\n

With the above aperture adjustment, we left the shutter speed alone. However, we could have made two adjustments, one to aperture and one to shutter speed. Remember, shutter speed does not affect your flash lighting. Here is how you can control each type of lighting separately using a two-step process:<\/p>\n