Here’s is another installment from my travel photography course at Matador U. This time the assignment is practicing with ISO. I’ll be honest. I don’t mess with ISO much. I often forget to adjust it and if I have a tripod on hand I don’t find many opportunities to change ISO. Today I have an opportunity to share some ISO photo samples.
Note: I’ve reduced the resolution on all of these photos for faster webpage loading; otherwise, no other edits have been made to these photos. And, yes, I know that these could use some editing, but for the purpose of this exercise I wanted to keep them as is. If I was going to use any of these photos in a story I would have done additional editing.
Purpose of ISO
From Matador U’s travel photography course:
The letters ISO on your digital camera refer to the “film” speed. Even though your digital camera doesn’t use traditional camera film, the ISO setting still has the same function as on older film cameras, in the sense that it determines the image sensor’s sensitivity to light. The most common ISO range is from 100-800, but some go as low as 50 and as high as 6400. Unlike the confusing aperture numbers, the ISO numbers are easier to remember: the lower the number, the slower the speed; the higher the number, the faster the speed. Setting the film speed before you take a photo is of the utmost importance. In bright or sunny conditions, a low ISO is generally used — 50, 100, or 200. If the sky is overcast or it’s late evening, then the 400-800 bracket is best. During night or in cases of low light (such as at an indoor concert or outside during twilight), selecting a higher ISO setting will increase your options in terms of setting the shutter speed and / or aperture. Be aware, though, that there’s a price to pay for using higher speeds: it’s called “noise” or “grain.”
I want a shutter speed of 1/6 second to capture the water to my preference. I also need a large aperture so that most/all of the photo is clear. However, the sun hasn’t quite risen above nearby Mount Index. My only choice is to change the ISO. I started with the lowest ISO of 100 and shot the same composition at every ISO setting my camera is capable of shooting. The photos start underexposed at ISO 100 and end overexposed at ISO HI 2. Which is your favorite? I’ve noted my favorite at the end of this post.