Seriously, Week 1

This week was the first class of my six-week "Seriously Fun Photography" class. So what did we cover?

We learned that to control exposure, we need to work with three related elements:

Sensitivity:
This is the ISO "speed" of a digital sensor or of film. ISO 100, 200, 400, 800, 1600 and 3200 are available on many cameras (but not all), and you should take some test shots with yours to find out if the higher ISO settings are usable or not. Figure out the fastest ISO speed you find produces acceptable shots on your camera -- you'll need to switch to it sooner or later. Notice that each ISO speed is twice as sensitive (or half as sensitive) as the next.

Aperture:
The f/stops to memorize are f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22. If you forget these, make two columns, and at the top of the left one write 1.4 and at the top of the right one write 2.0. Now double each number as you go down the column (rounding off when needed). Changing one stop lets in twice as much light (or half as much, depending on which direction you go. f/2 lets in a lot of light, f/22 lets in very little light. So if you took a picture using f/8 and it seemed a little too dark, you would switch to f/5.6. If you took a picture using f/8 and it seemed a little too bright, you'd switch to f/11.

Shutter Speed:
The common shutter speeds are:
1/1000th of a second
1/500th
1/250th
1/125th
1/60th
1/30th
1/15th
1/8th
1/4th
1/2
1 second.

-- As a rule of thumb, if you are moving and you're subject is moving, you'll want to be shooting at 1/1000th of a second to get a sharp picture.

-- If you are still but the subject is moving along, it would be good to be at 1/250th or faster.

-- If you and the subject are both relatively still, you can probably handhold the camera as slow as 1/60th, but slower than that and you'll get a soft picture because of camera shake caused by pressing the shutter.

-- At speeds that are slower, you'll need a tripod to steady the camera, and probably want to trigger it using the self-timer or a release.

-- Many decent cameras have higher shutter speeds, and these are very useful for action or sports.

Notice that the relationship of these shutter speed settings is also doubling (or halving) the amount of light that hits your sensor.

So, from a technical standpoint, as we approach any photo situation we'll want to decide on an ISO setting, a shutter speed and an aperture. The three are interrelated and all use a doubling / halving system so it is easy to calculate how to change them when needed.

We also started considering focal length: We learned that:

-- on a 35 mm film camera, a 20mm lens is very wide, and that on a digital APS-C sensor it is wide.

-- on a 35mm film camera, a 50mm focal length lens feels like it sees about the same as your eye and is considered "standard." on an APS-C sensor as you have on most DSLR cameras, a 50mm lens is slightly telephoto -- very good for basic portraiture.

-- on a 35mm film camera, a 90mm lens is telephoto and would be very good for portraits. on a DSLR it is even longer and works great for making a flattering portrait.

For sports or similar shooting, we'd want to be able to go to 200mm or 300mm in focal length. For some architectural photography, or in other cases where we need to go really wide, we might need to to get something like a 10-20mm superwide zoom.

We found that shooting with a wide-angle focal length (like the 18mm length common on "kit lenses") most space seemed to "expand" compared to what our eyes see. Switch to a telephoto length made the space seem to "compress."

At the end of the class we tried an experiment where we tried making some portraits using our new knowledge of focal lengths. We shot a photo of a person using a wide focal length, standard focal length and telephoto focal length. Then we repeated that but moved our position so that the framing on the person stayed the same in all three shots.

And More on the Rule of Thirds

The above image of a man photographing a museum label was a quick snapshot taken with my pocket camera. Still, I tend to compose using the Rule of Thirds.

The Rule of Thirds

On Friday night, we stopped by the Met for a gallery talk on David's The Death of Socrates. Great lecture. Of interest to photographers: this painting serves as a perfect example of composition using the "rule of thirds."

The basic idea photographers can learn from this: rather than automatically placing the subject dead center of the frame, explore what happens when you place the main subject -- in this case, Socrates face -- at one a point 1/3 from the top of the frame, or 1/3 from the side of the frame, or at the "node" 1/3 from each.

While life will rarely unfold in front of you in perfect composition, thinking of the photographic rectangle of film or digital cameras as divided into three parts is a powerful strategy. For many images, setting up a 2/3 versus 1/3 arrangement creates a much more dynamic composition.

The Sunny F16 Rule

I have a great light meter. And the meters inside a modern digital SLR are usually spot on, if used correctly. Still, in the same way it's valuable for a musician to have perfect pitch, it's probably good for a photographer to have some sense of light. So, how can you develop that?

Well, it's a bright, sunny day, I've got my trusty Zorki 6 and a Metro card. There's no meter in the Zorki rangefinder -- so I can carry a meter or I can make my best guess as to the right exposure....

Today I'll guess. That's a great way to train your eyes -- but you'll need a good Rule of Thumb to work from: The Sunny F16 Rule. On a typical day, your exposure can be calculated in the following manner:

Shutter Speed:
What film speed or ISO setting are you using? To start the calculation, set that as your shutter speed.

Aperture:
shadows sharp: F16.
soft-edged shadows: F11
barely-there shadows: F8
very overcast: F5.6

Since I have 400 speed film in my Zorki, I'll start with my shutter speed at 1/400th of a second. Then, I'll look at the shadows I see and decide: sharp, soft, or very soft? F16, F11, or F8. If the clouds roll in and I notice it's darker, then F5.6.

So, I might start at 1/400th of a second and F16, but if I see the light level lower a bit switch to F11. If I see the shadows have faded, then F8. Easy, and great training for your eyes.*

*(Of course, while I want to make things simple for this post, in the real world there is a tiny bit more complication: I like to slightly overexpose black and white negative film. Like many, I find a 1/2 stop of overexposure makes a better negative, generally, even though I would avoid overexposure in digital whenever possible. So, to do that I would make a little adjustment to my calculation: my 1/400th shutter speed would change to about 1/250th. That's very convenient, since the Zorki doesn't have a 1/400th setting anyway, so I'll switch to 1/250th at F16 for the bright sun.

Then, since I find 1/250th isn't quite fast enough for walking along street shooting -- Garry Winogrand used 1/1000th when possible on the street -- I would switch to the Zorki's fastest shutter speed of 1/500th and make the corresponding change to my aperture.

So, I would shoot at 1/500th and F11 in sharp shadows, 1/500th and F8 when the light drops a little and I see soft shadows, and 1/500th and F5.6 when the light drops further. If the clouds roll, then I'd be at 1/500th and F4.)