I received a call from an e-friend, Jane Lyons, about her basketball pictures taken in a gym.

She’s using:
Nikon 40DX
A kit lens of some sort I’m guessing that 18 mm to 55 mm f3.5 – f5.6.

I’m on a Mac running OS 10.5.5.

After I downloaded her pictures, I selected the icon of her picture on my desktop then right clicked or “Control” click to “Get Info”.

This is what I learned about the settings she used on.

There are definite advantages to digital.

One of them being the embedded EXIF data which comes with jpegs.

Between using the Finder or Photoshop, I gleaned the following info:

1. Shutter speed was 1/25 sec
2. Aperture was f5.3
3. Focal length the picture was taken 165 mm.
4. ISO 1600

What that means is this, the light levels were enough to make a well exposed picture.

However to “freeze” the action and to eliminate “camera shake,” a higher shutter speed is needed.

Since Jane shot her pictures at 165 mm setting, she’ll need a shutter speed of 1/250 sec to successsfully hand hold.

But the moving action of the players may require a shutter speed of possibly 1/500 sec.

There is a rule-of-thumb for film photography that says you should use the reciprocal value for shutter speed of the focal length you’re using to hand hold.

This rule-of-thumb needs to be modified because of the 1.6x magnification factor due to the CMOS of CCD sensors.

If you’re using a 50mm lens, you should be using a shutter speed of at least 1/125 of a sec if you’re not bracing. 50 x 1.6 = 80, so your shutter speed should be 1/80 sec.

Too much to remember? Don’t sweat it. Cough up $1700 and buy a IS (image stabilized) Canon lens or VR (Vibration Reduction) Nikon’s 70-200 f 2.8 lens.

Supposedly the built-in gyroscope in those lenses allow you to handhold successfully lower shutter speeds. As they say, your mileage will vary …

Camera shake is simply the operator of the camera jostling the camera during the exposure. How well you can hand hold the camera depends on, not just how much caffeine you’ve had, but also what lens you’re using.

Any lens that is longer than 50 mm focal length has a tendency to magnify every little movement. That’s why you always need a tripod or stand when you look through a telescope.

Given the aperture is set at the biggest or widest opening and her camera’s ISO is set to 1600 (maximum), these are her options:

• Use an external flash
• Use a faster lens
• Try panning the action?

That internal pop-up flash has a very limited range.

The more you use that flash, the faster the battery will die.

On a practical note, some schools may not like flash photography during games because it blinds the players.

I don’t buy that explanation by the way. Pro basketball games are shot using strobes that are mounted high in the rafters over sports arenas.

A faster lens may or may not be the answer depending on the light levels in the gym in question.

In the case of Jane, at ISO 1600 f5.3, she got an exposure of 1/25 sec.

So if she bought a 50 mm lens with a maximum aperture of f1.8, she would be letting in more light, about 2 f-stops of light going from 5.3 to 1.8.

To prevent over exposure she will need to let in less light by increasing her shutter speed 2 f-stops to 1/125 sec.

Look at the above graphic. If you use a bigger aperture when shooting in manual mode, you have to adjust the shutter speed accordingly to get the equivalent exposure so you don’t over expose the image.

Numbers for apertures and shutter speeds are reciprocals. 1/60 sec lets in one f-stop less light than 1/30 sec just as f4 lets in one f-stop less light than f4.

That may not be quite enough shutter speed to freeze the action if you ask me.

Depending on whether the action is moving across the plane ie. left to right or whether the action is coming towards or away from the camera, she may be able to get some good results.

That 50 mm lens costs about $100. Is it worth it?

I think so because it is what’s called a “fast” lens. You will be able to get that look or bokeh in the background when you shoot with your aperture wide-open with this lens.

Thank you Jane for sharing your pictures. Your contribution and questions, as always, will help others who read this blog.