Basic photography

A certain 20-something who lives in my household – but who expects to move to Asia in the near future – told me yesterday that this blog has gotten stale, that it was much more interesting when I talked more about photography and less about social networks. I think it’s just a matter of taste, but since he has occasionally been right, this post is going to be about photography. And since he’s leaving the country and taking one of my cameras, I’m writing this post for him: it’s a 5 minute pocket version of what I’ve learned about manual settings. Now I expect him to send me some great photos.

Here goes.

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The manual world consists of aperture, shutter speed, and ISO.

Aperture

Columbine

Aperture of f/2 means a nice blurry background

Aperture is the size of the hole that lets light in. Example aperture settings: f/2, f/2.8, f/4,  … f/16

Why care about aperture? The lower the f-stop number (i.e.the bigger the hole), the more things outside your area of focus get blurry. For example, an aperture around f/2 will cause a blurrier background than an aperture around f/16.That was a real revelation to me when I figured it out last summer!

The smaller your aperture — i.e. the higher the f/ number — the less light gets in, which means that your image gets darker. So, an aperture of f/2 – which lets in lots of light – will be brighter than one of f/16, all other settings being equal.

Shutter speed

Shutter speed is how long is the hole open for. Example shutter speed settings: 1/125, 1/160, 1/200, 1/250, … . Those numbers are in seconds, as in: 1/125th of a second. But, they can go down to 1, 2, 5, or more seconds. You can even set it to stay open as long as you hold the shutter button.

A Pitch and a Miss

A faster shutter speed would mean a less blurry baseball

Why care about shutter speed? The faster the shutter speed, the more the action is frozen… or, the slower the shutter speed, the more you’ll see moving things turn blurry. So, a lot of sports photos are shot with a really fast shutter speed.  The darker it is (outside, inside, wherever you’re shooting) though, the slower/longer shutter speed you may need just to capture your subject… which means that your photo could end up blurry if you’re not completely still. (That’s why people use tripods.) Occasionally you might want to use a slower shutter speed – with a little motion blur – for effect. You’ll want a really slow shutter speed if your taking photos of, say, the moon.

The shorter/faster the shutter speed – e.g. going from 1/125 to 1/500 – the less light gets in, which means that your image gets darker.

ISO

ISO determines how sensitive the camera is to light. Example ISO settings: 100, 200, 400, 800, 1600, …

Why care about ISO? The lower the ISO number, the more detail will be captured. Depending on the camera, images can start to get grainy at around 400.

The lower the ISO – e.g. going from 800 to 100 – the less sensitive to light your camera is, which means that your image gets darker.

In the end, the image you end up with depends on your combination of these three numbers (along with your subject and focus, of course!)  The flexibility that you have depends on your camera and lens.  To some degree, it’s all a big tradeoff.

If your shots are too dark, you can:

  1. Increase the aperture (this wording is tricky, since it actually means going to a lower number – e.g. going from f/4 to f/2); or
  2. Decrease the shutter speed, say from 1/200 to 1/125
  3. Increase the ISO.

There are guidelines for choosing the best aperture for sunny / cloudy / dark conditions – Google “Sunny 16” and you’ll see approximately 154,000 sites telling you what they are (here’s a sample).

Two more things to be aware of, then I’m done.

Metering

Pay attention to the metering mode if you’ll be taking photos of things that are mostly white or mostly black. The default settings generally deal with situations where the reflection of light is pretty average (“18% gray”, which is darker than you would expect.) If you’re going to be taking pictures in snow, at a hockey game, or of a black dog on a blacktop driveway, though, you may want to go with spot or partial metering, or you’ll lose detail. You can also use exposure compensation or exposure bracketing to fix things if they’re just not right.

White Balance

White balance is that thing that helps your camera compensate for different kinds of light – sunlight vs. incandescent light vs. fluorescent light, for example. A poorly set white balance can make a gray squirrel look brown or purple flowers look blue.

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So that’s it! Blog reader: if you’re a seasoned photographer and have some corrections, please let me know (quickly, so that I don’t lead anyone astray.) If you’re a newbie, I hope this helps. Most of this was off the top of my head – which should explain all the non-technical language – but I’m including a couple links to some nice reference pieces (that I found after most of this was written) below. There are an endless number of places online to find this information, really.

About aperture, shutter speed, and ISO: http://www.cambridgeincolour.com/tutorials/camera-exposure.htm

About metering: http://www.cambridgeincolour.com/tutorials/camera-metering.htm

Happy shooting!

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8 comments

  1. I wanted to add to what you said in terms of higher f-value equals darker image and vice versa. You can also create a darker photograph with low f-values by throwing out everything in background using a low depth of focus and pointing against the source of light. Pointing at the source of light may give you bokeh. For example in this one I dialed in f5.6 (lowest I get at 55mm with my kit lens) and also used EV = -2 to get the shadowed background.

    With a higher f-value, you actually get a higher depth of focus that translates into more number of light sources and finally a flattened photograph with multiple objects in sharp and focused state, compensated by adjusting (mostly lowering) shutter speed or ISO. That is, for same shutter speed and ISO, higher F-value will actually over-expose your photo. (Now I want to test and confirm this tomorrow!)

  2. Super-useful! I’ll be referencing this. The only confusing part is with the aperture stuff, when you say “higher” and “lower” and “increase.” I’m not totally clear on which way is up for that, so maybe you could be more specific on that part?

    When I was at the aquarium all my pictures turned out reaaaaally horribly blurry, until I increased the ISO by a lot, at which point they were fairly grainy. So what would you recommend for that kind of thing?

    • Hi there, I’ve updated the “aperture” section in an attempt to make it more clear. Any better?
      Hmmm… the aquarium question… hard to say, and of course it depends on what you can do with your camera. I think we’re both better off if I give you a link to this site that has some pointers: http://www.montereybayaquarium.org/vi/vi_tips/phototips.aspx

      Here’s one aquarium picture that I took last fall (without reading any pointers). I gave it a nice looong exposure (1/15) with ISO at 200 and was just lucky it wasn’t terribly blurry.

      From Florida 10-20-2010


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