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Photography Question 

Michelle B. Prince
 

Speedlight


I have always been told that outdoor portraits are best done in aperature priority mode. I have a speedlight but don't really know when I need to use it. I try to use it when my shutter is too slow, such as in a shaded area. the photos are still blurry. When using the speedlight should I be shooting in manual mode? any tips would be greatly appreciated.


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June 20, 2005

 

Michael H. Cothran
  Your shooting mode should be chosen based on your present shooting environment and WHAT you are shooting.
Most amateurs would simply turn on the Program mode, and fire away. However, if you want to have full control over your shooting environment, here's some well-experienced advice -
When shooting outdoors with both flash and ambient light, remember -
1. Control the flash with your f-stop
2. Control the ambient with your shutter speed
I cannot stress enough the importance of remembering AND understanding this.

Now, you have to make a choice before you take the first picture, and before your subject is ready: Based on your shooting environment, do you want the flash to be predominant, or the ambient? For outdoor portraits, you want the ambient to be the brighter of the two light sources. Why? If the flash is brighter than the ambient, it looks too artificial. You want to meter for an accurate ambient light exposure, then lessen the flash from -1/2 to -2 stops. The amount depends on your taste - experiment to find out. To do this, set your camera to Aperture priority, then dial in the negative amount of strobe light on your flash unit. If your Speedlite works in 1/3 increments, use -.7, -1.3, and -2 to experiment. It's that simple.

A situation outdoors where you might want the flash brighter would be shooting flowers. I'd make the off-camera flash the "main" light, and lessen the ambient by dialing in a shutter speed 1 or 2 speeds faster than required.
If you want absolute total control over each light source, go to manual. If you would like to try full Manual shooting outdoors, let me know, and I'll be glad to walk you through the steps.
Michael H. Cothran
www.mhcphoto.net


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June 20, 2005

 

Michelle B. Prince
  Wow. Thank you. I am going to sit down and read this carefully.


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June 20, 2005

 

Michelle B. Prince
  I have not used my flash often but I guess I am using it incorrectly. If I am taking a picture of a person in a shaded area using aperature priority with the aperature about 5 to get the blurred background, I often find that my shutter is not fast enough. This is when I have tried to use the flash. In this case it is brighter than the natural light, and as you would expect the photo looks horrible. The extra light does not even seem to get rid of the blurr coming from a too slow shutter. I always photograph people. Should I then use the flash for fill and not to light up a too dark area? What would you do if your shutter was too slow? If change the setting to shutter priority I can get my shutter up but the aperarute seems to stay at 4.0. Maybe it's just a place a photo can't be taken well.


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June 20, 2005

 

Michael H. Cothran
  For people shots outdoors, I would always have the flash less than the ambient light (1/2 - 2 stops less). It just looks more natural. Shooting around f5.6 - f8 is ideal. Shooting in the shade is going to slow down your shutter speed considerably. If you're not using a tripod, you probably should be in this situation, but you still have to be concerned with subject motion. After careful metering, if you cannot come up with a useable shutter speed for fill flash, I think I'd find another location, or turn off the flash, and angle the person to where the natural light is most directional. The use of a reflector would help, but with natural light in the shade you will need a "black" reflector to place over the head of your subject. This will force natural light onto the face from a better angle than straight above.

If I haven't done this in the past, allow me to introduce you to Monte Zucker - one of the foremost modern portraitists of our time. He current writes a monthly column for Shutterbug magazine, but has been foremost in the portrait business since the 1960's. He is a master of his trade,often lecturing at national PPA conventions, and most importantly, he is a master teacher. He shares all his techniques with the world. Do a google online, and read everything the man has written. He is an expert in outdoor lighting, and often creates his beautiful images with just a reflector or two. Visit Shutterbug magazine online, and read all of his past columns. Absorb his techniques. You won't be sorry.
Michael H. Cothran
www.mhcphoto.net



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June 21, 2005

 

Jon Close
  Michelle - I see by the captions under the pictures in your gallery that you are using and EOS camera.

See http://photonotes.org/articles/eos-flash/ for a comprehensive explanation of how to use the EOS cameras and speedlights.

Note that with a dedicated speedlight that EOS cameras will automatically switch the flash exposure from main light to balanced fill flash based on ambient light levels. Any flash exposure compensation you set will be in addition to what the camera is calculating - whether in P, Av, Tv, or even in M mode.


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June 21, 2005

 

Michelle B. Prince
  Michael, thanks for the info. I will check all that out. I was told and it seems to be a good rule that when shooting AV to make sure the shutter speed is at least if not a higher number than your focal length. For the most part that is how I have been shooting outside. When the shutter was not high enough I would try to freeze action with the flash but it did not work. What did you mean by a "usable shutter speed for fill flash"? I am going to check out all that you and Jon have recommended to try and get these answers as well. I am moving in two weeks but want to take a course here on lighting after I get settled.


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June 21, 2005

 

Michael H. Cothran
  "What did you mean by a 'usable shutter speed' for fill flash"?

Michelle,
Good question - complicated answer! I'll try to answer as concisely as possible.
Modern cameras/lenses use one of two types of shutters - focal plane or leaf. Virtually all 35mm SLR's and DSLR's use focal plane shutters. These shutters are housed in the camera body, and incorporate two curtains that travel across the film or sensor to expose it to light. They form a slit as they travel across the film. Hence, with faster shutter speeds your film or sensor is never exposed to light all at one time, but only as the slit travels over it. Since flash involves a burst of light at such a high rate of speed, you must use a shutter speed with a large enough slit so that it will expose ALL of the film or sensor at one time during its path across. This is why your camera has what's known as a "maximum flash sync speed." This is the fastest shutter speed your camera model fires in which the entire film or sensor surface is exposed at one time.

By "useable shutter speed" I refer to this phenomena, if you will. You can use any shutter speed slower than your max sync speed, but you can't go higher. Outdoors, this may present a problem. If your max sync speed is, say, 1/125th sec, and you are shooting in sunlight @ f5.6, your "correct" shutter speed may be 1/500th or 1/1000th sec. So you cannot use these apertures in this situation since they will not provide you with a "USEABLE" shutter speed.
In summary, and in Aperture Priority mode, you must consider your chosen f-stop in conjunction with what the appropriate shutter speed will be, and be sure the latter is within your camera's range of "useable" shutter speeds with your flash, AND, will provide you with the appropriate exposure at your chosen aperture. And by "appropriate" I mean - do you want it to be correct, a little ligher, or maybe a little darker.
Hope this helps without muddying the waters too much.
Michael H. Cothran
www.mhcphoto.net


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June 22, 2005

 
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