This week is all about shutter speed and ISO. Shutter speed is exactly what it sounds like, its the speed at which the little opening on the lens shuts to take your photo. A faster shutter speed can capture movement in a freeze frame; a slower speed will show moving elements in a blur and convey motion. The assignment was to take photos of running water at different speeds and compare them. This is where ISO and my problems began.
The best way I can explain ISO is that it is the speed at which the photo develops. With film cameras, this was the number listed on the film box. Photos are developed by exposure to light, so if you have less light, you need a higher ISO. If you are using a fast shutter speed, the little door opens and closes quickly, not letting much light in, so we use a faster ISO to compensate.
The assignment specified to use an ISO of 1600, this is the fasted setting my camera would allow anyway, and put the camera in Shutter priority mode. The first few photos I took at slower shutter speeds were not that bad. Here's one:
One second is actually considered a pretty slow shutter speed. I had to use a tripod because any camera movement would have totally obscured the shot. Notice how the water is sort of blurry as it hits the glass. This next shot is a bit faster.
1/50 of a second
Now you can see more definition as the water hits the glass.
You are about to see where I started having problems. The situation is that high speed shots really require good (read: natural) lighting. The only sink in the house near a window is in the kitchen, but unfortunately those particular windows face a mountain side. So good, natural lighting is pretty much impossible. If I hadn't waited until the last minute and it weren't blue cold today, I guess I could have gone outside and used the hose or spigot on the side of the house. But I'm a wimp, and it was frosty, so I didn't. Here's an even faster shot:
1/500 of a second
You can see a lot more definition to the water, even droplets are beginning to be made out in the stream. But the problem with higher ISO is noise, or in layman's terms, the graininess of the photo. I had to increase the brightness the most my little edit slider would let me and bump up the contrast as well so you could still make out the photo. This is the best I could do with it since I am still totally ignorant with photoshop and am currently refusing to even start the program because I'm intimidated. This next shot is the fastest I attempted to shoot:
1/1000 of a second
If this photo weren't so distorted it brings to mind the TV screen in poltergeist, it would be totally cool. If you look closely you can really see the little droplets and how the motion is stopped. You can also tell that it's a faster shutter speed because the photo is even darker.
In conclusion, I really wish I'd had better lighting, but I think you get the gist of what I am attempting to learn. Hopefully I'll get some spare time and a few moderately warm days this week to play around outside a bit and have something I'm a little more proud of to post.
If I get really ambitious, there is a creek nearby that could be promising...how's that as a cliff hanger for ya?