ISO 101

ok, so i got this fabulous camera for a belated christmas present and i've been so impressed by the no-adjustment shots i took at the beginning that i never bothered learning how to use it. now i can see that even sooc (straight-out-of-camera) shots are better when you know how to use the right settings. so today i'm trying to learn.

there are 3 main things to adjust on your DSLR camera relating to light levels

1. aperture (how much light gets in- establishes depth of field)

2. shutter speed (how long the light gets in- establishes movement)

3. iso (what type of "film" you use)

iso is the most complicated for me to understand so i'm starting with that one. and just so you know, i'm no expert. i just learned this today. meet my model :)

basically, as i understand it, iso relates to both your aperture and your shutter speed. for today's exercise the depth of field does not change (f/4.5) because that's just what i picked. sheesh! so many questions. ok, f/4.5 is the biggest (even though it's the smallest number) that my aperture will open. this creates the most depth of field (blurry background). and in my dream world i would own a macro lens (or some other type of lens that i haven't learned about yet with a wide aperture) so i like my aperture set at f/4.5, period.

the iso, or 'film type', you select depends on your shooting environment. my EOS Rebel xsi has iso options of 100, 200, 400, 800, and 1600. also, the higher the number the more noise in your photo (the grainier it looks). i am shooting inside with natural daylight coming in the windows. so before i start photographing i figure that i will probably get the best photo with an iso of 400 or 800 because of my lower light levels. 100 or 200 is best for a sunny day outside. (i know this because i read about it, not because i just know it.) but i'm going to shoot all my iso options to see what my M setting on my camera will recommend for shutter speed. remember my aperture is constant, f/4.5. i also know that a shutter speed slower than 1/40 probably needs a tripod but i am going to just rest my elbows on my desk (please ignore the messy desk). so here goes.

iso 100

shutter 1/4

iso 200

shutter 1/8

iso 400

shutter 1/20

iso 800

shutter 1/40

iso 1600

shutter 1/80

so you can see that as my iso increased my shutter speed got faster. and the ideal iso in this situation is 800 with a shutter speed of 1/40. and the 400 iso is even better but at risk to needing a tripod. any iso lower than this would need a tripod if you didn't have a desk to rest your elbows on and the iso 1600 with the faster shutter speed of 1/80 probably needs a wider aperture to let more light in. remember i don't have groovy wide aperture lens to work with? so the 1600 iso is not right for me.

ok, this was really an exercise to help get it straight in my head and i worked some.

maybe.

so if you have any questions i probably don't know the answers but ask away if you want to.

confusing enough for you?

and, by the way, this photo is a total fake. i'm really left eyed but that made my entire face behind the camera and the picture looked stupid.

and please ignore that dog hair on my filter. thank goodness for filters.