What is dragging your shutter?

Posted on October 19, 2011

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My last blog seemed to generate more questions than it answered. The largest question from the last blog was “What is dragging your shutter?”  There were a few others, too, so let’s see if we can cover a few of those questions.

Let’s start with you as a photographer and being an artist. This means you will have to make decisions each and every time you shoot an image. You can’t expect something special to appear from just going out and shooting images. You need to take some time and plan for the images you take. This means knowing where you are shooting, having some idea of the images you want to capture (concept, posing, and lighting), and have some goals for the shoot. How many people take images of the location you plan on shooting a model some time before without any models? Do you ever walk around the area and just take a look at what things would be interesting or a place that you might use for the shoot? Do any of you make any plans on poses you want the model to do with lighting directions? Is there a story or a plot line to tell your model to help them with working the image or concept you have? All of this is stuff that you should be doing to some extent before you shoot.  Keep in mind that this plan shouldn’t be so rigid that you can’t adapt to changing situations – things like weather, where your model is better or worse than expected, equipment failures, etc. When you make these choices, you are doing them as an artist.

As I indicated, I tend to drag my shutter. This is one way I shoot and minimize the impact of flash on the overall image I capture. This means shooting slower than you would normally when you use a flash. Most photographers will shoot at either their shutter sync speed or a 60th of a second. Are you one of those people? Do you know what happens as you slow down your shutter speed? Quick… What is it? The longer your exposure speed with a flash, the more of the ambient light that you capture. If you shoot only at your shutter sync speed, you will have a lot of blacker backgrounds, and a lot less of what is in the back of what you are shooting. As you slow down the shutter, more of the background light exposes the area and you have more detail from it. The black lines from the shadows tend to be softer in relation to the background light.  So, what speeds would it be? Again, this depends on you as a photographer and your style of shooting. Play with this technique and even mix it in with fill flash. You might be amazed at your results and some of what you get from doing this. Contrary to what many people may think, there is little impact to the rest of the exposure being made. This is because the flash tends to overtake all the other light in the image, leaving the only real control for the amount of light is aperture other than the amount of light output on the flash. Aperture is also the control for the amount of depth of field you have in your image, so don’t forget this when you change the aperture for exposure.

Another question that was asked was “How do I control the softness of the flash?” This is handled many ways. One way is to use a bounce flash. Another is adding some kind of device to the flash to make it softer – adding some kind of diffusion material. There are many good products out there that do this type of job. Get one and play with it to learn how to use it. If you can’t afford one, start with a simple white card attached with a rubber band. Use it to reflect some of the flash to the subject to reflecting all of the light. When you have exhausted a white card, move to tinfoil (both sides). Each of these do different things to the light. Try bending and changing them in different ways to control and feather the light differently on the subject.

Another question is “What constitutes a good piece of glass in a lens?” This is more difficult to answer.  The first place to start is through research and what different testing panels have indicated about the lens and what they say about the lens. Know that there is more to a lens than it’s glass performance, so read the reviews critically. Over time, you will learn what is and isn’t a good piece of glass. Certain names and products will always appear over time, and because of their different costs, you will find the best values for the money and those that are worth the extra money. Take the time and learn about any lens you are thinking of purchasing. Use one if possible.

I hope this answers a few of the questions from the last post. If not, feel free to send me a message.

Edit: I was asked about how slow do I shoot? The speeds I shoot are much slower than most people should shoot when dragging their shutter without a t tripod. As you get more stable and better at dragging your shutter, you can get down to about 1 second without too much blur (usually it is your subject, and is only a part of your subject like their mouth or eyes or hands). A common rule of thumb is to use the inversion of your focal length in seconds. For instance, if you are using a 50 mm focal length lens (effective focal length, so if you are using a smaller sensor then the focal length would be higher), then you can shoot down to 1/50 of a second without a blur. For me, I wouldn’t have a problem shooting this down to a tenth of a second but again, practice, practice, practice. I will typically throw away up to about a third of the images I create when shooting this slow. The following image was shot at 1/10th of a second, F2.8 and was hand held during shooting for an independent movie.

motion issues with dragging shutter picture

Click for larger image to show motion issues

Edit: A friend mentioned this to add the following comment to the post – flash intensity and aperture expose the subject while shutter speed exposes for the ambient light.

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