Welcome another edition of our Tutorial Tuesday series here on The Digital Press blog! This is Part 2 of our 4-part photography series all about the exposure triangle. If you happened to miss it a couple of weeks ago and need a recap, you can find Part 1 HERE. To refresh your memory, in that first post we introduced the idea that photography exposure depends on three settings: ISO, aperture, and shutter speed.

Today we’ll be focusing on that first variable — the ISO setting in the exposure triangle.

ISO is the sensitivity of the sensor. A high ISO means that the sensor of the camera is more sensitive to light, that it will “capture” every bit of light available, so to speak. More light is let in when you choose a high ISO number; conversely, less light is allowed in whenever you choose a lower ISO number.

What does this mean when you’re taking photographs? Well, for example… on a bright, sunny day outside you can choose a lower ISO (usually 100; sometimes 50) on most cameras. The opposite is true when you are indoors taking a photo in a room with very little light (at night, for example… or in a room with a tiny window and no lamp on). In that scenario, you would need to choose a much higher ISO (6400 or higher, etc.).

Here’s a look at a couple of outdoor/indoor photos, and the corresponding ISO used to capture the image…

As I mentioned in Part 1 of this series, every setting of the exposure triangle has a “side effect.” In other words, each setting has consequences on the exposure but also on something else in the picture. The side effect of ISO is noise. In the film days, it was called “grain” because the sensitivity of the film corresponded to the size of the grains of salt (the less sensitive the film, the smaller the grains and the cleaner and smoother the image appeared). With digital cameras we use the word noise to express the same thing as the film-age term “grain.”

Here are two examples of the noise that appears on images with a very low ISO and a very high ISO. As you can see, high ISO = more light allowed in but more noise; low ISO equals less light allowed in (so I had to adjust the other settings of the triangle), but less noise…

See the difference?

Even if grain was part of the charms of film photography, oftentimes digital noise is considered to be a bad thing. It can be distracting when it’s too strong, and it can create color artifacts. One way to avoid “bad” noise is to correctly expose the image in the first place, even if that means upping the ISO (noise will be better on an image correctly exposed with an ISO of 12800 than on an image with an ISO of 3200 that needs to be brightened in post-processing.

Here is another example that illustrates this idea…

First, the SOOC (straight out of camera, no post-processing) image at ISO 12800:

And next, the SOOC image at a much lower ISO of 1600, with all other settings remaining the same (hence the severe underexposure):

And finally, the second image… but with its exposure corrected in post-processing:

You can already see in the full image that the noise is much worse in the last picture (corrected) than it was in the first of the series, up above… even though the ISO is much lower. It’s even worse if you zoom in:

Moral of the story: it’s typically much better, in order to avoid bad noise, to take a picture with a high ISO but a good exposure… than it is to take an underexposed picture with a low ISO that requires brightening it in post-processing.

There are so many different cameras on which you can choose the ISO (even some smartphones!) that I will advise you to read the manual or do an online search on how to change the ISO on your own gear.

*TIP* If you are just starting to learn to shoot manually (where you, rather than than the camera, pick the settings)… ISO is a setting you can set on “auto” and let your camera take care of,,, so that you can focus on aperture and shutter speed. Once you get the hang of those, you can then start adjusting the ISO yourself.

We will explore those other two variables (aperture and shutter speed) in the next two parts of this series (coming in June, every other week). See you soon!

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About the author  Chloé is in charge of PR and communication for her small town by day, a digiscrapper “by night,” and a photographer whenever the light is beautiful. She recently became a very happy mom to an adorable little boy and is enjoying the last days of her maternity leave.

Hello, and welcome to another edition of our Tutorial Tuesday series here on The Digital Press blog! This week, we’re beginning a really awesome 4-part series that will run every other week for the next couple of months to help you with your photography!

As scrapbookers, you may have read photography tutorials in the past (including the great ones we have here on The Digital Press blog)… and in doing so, you may have seen the term “exposure triangle.” That’s the concept we’ll explore with this 4-part tutorial that will, I hope, help you better understand the notion and use it in your own photography!

First of all, let’s see what happens in the camera when we take a picture. Basically a “hole” opens to let the light come in and hit the sensor that will capture it. Exposure is the amount of light in a photograph. An OVERexposed picture is too bright (details are lost in the highlights, the brighter areas of the image) and an UNDERexposed picture is too dark (details are lost in the shadows). To expose a picture, three settings come into play, that’s the famous “exposure triangle”. Those three settings are ISO, aperture and shutter speed. 

ISO is the sensitivity of the sensor. In the film days, each film had a set sensitivity, but today we can change it on most cameras. A high ISO means that the sensor will take more light in, a lower ISO means it will take less light in. ISO go usually from 100, sometimes 50, up to 12800 or more.

Aperture is the size of the “hole” that opens in the lens to let the light come it and hit the sensor. Let me get math-y for a minute here. This number is expressed as a fraction: f/2 for example. It means that the diameter of the hole equals the focal length of the lens (f) divided by the aperture numbre (2 in my example). That’s the reason behind the fact that the SMALLER the number, the BIGGER the aperture (the hole) and hence the MORE light entering. With a 50mm, for example, an aperture of f/2 will give a 25mm (50/2) diameter of the hole, when an aperture of f/10 will give a 5mm diameter (50/10). So, in short: big number = small aperture = small hole = less light in, small number = big aperture = big hole = more light in.

Shutter speed is for how long the “hole” remains open and let the light in. On my camera, it can go from 30 seconds to 1/4000th of a second. The longer it remains open, the more light goes in.

Here is a simple analogy: if taking a picture is like filling a bucket with water. ISO is the size of the bucket (that is meant to hold more or less water), aperture is how much water comes out of the faucet (is it wide open or is it just dripping?) and shutter speed is how long the faucet remains open.

We talk about the exposure TRIANGLE because all three setting are dependent on each other. If you let less light in through one setting, you will have to let more light in with another one (or both) in order to have a properly exposed photo. Let’s see some examples.

First, here is a photo where each setting is “average”. It is correctly exposed (even if totally boring, I admit, but at least those subjects are easy to work with! LOL).

Here is a representation of the exposure triangle for this image with each setting:

As I said before, if you change only ONE of the setting, the photo become under or overexposed. In this second image I decreased the aperture (increased the number) and as a consequence the image is underexposed, much darker than the first one. To have a properly exposed image, I should have let more light in through either a longer shutter speed, a higher ISO, or both.

The different combinations of those three setting can be almost infinite while the result remains very similar. Here are three other examples, each followed by the settings.

First, I kept the aperture at f/8 (like in the previous photo) but I bumped the ISO (more light) and decreased the shutter speed (less light) so that the image would be properly exposed.

Then I chose to use the lowest ISO possible (less light) and hence I used the widest aperture possible on my lens (much more light) and the “average” shutter speed we had in the first photo.

Last but not least, I chose the highest ISO possible on my camera (much more light) and the smallest aperture on my lens (way less light).

If you observe carefully the images above you can see that changing the settings doesn’t only influence the exposure, it also has other consequences. Each setting has a “side effect” that we will explore in the next posts in this series, as well as how to choose and change our settings depending on the results we are looking for.

In the meantime, I hope the overall concept of “exposure triangle” is clearer to you. Don’t hesitate to ask (here in the comments or in the forums) if you have any questions! I’ll be back in 2 weeks with PART 2 of this series.

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About the author  Chloé is in charge of PR and communication for her small town by day, is a digiscrapper “by night,” and a photographer whenever the light is beautiful. She recently became a very happy mom to an adorable little boy and is enjoying the last weeks of her maternity leave.

Have you ever taken a picture, thought it was great, and then realized that there are shadows across someone’s face? The moment has gone, and while you love the photo, you wish you could see the individual features, the eyes, nose, mouth, etc., more clearly. Well, with the wonders of photo editing software, and a light hand, you can bring shadowed features into the limelight again. Let me show you how.

Here’s a photo of my son from, wow, a long time ago, at a local water park. He was having such a great time going up and down the large slides with the inner tube. It was tough to get a photo (he was so quick!), so I took what I could get. However, the more I look at this, the more I’d love to see his face in better light.  Yes, he has a good tan and is olive-skinned, but still …

I tried using Curves and Levels adjustments (I’m using Photoshop, and these can be found under the menu Image > Adjustments), but by increasing the mid-tones, it simply “blew out” the water, brightening what was already a lighter component of the picture – and the result looked unnatural.

I did, however, come up with a compromise that I really liked.

Step 1: Create a duplicate layer of your photo. (This is especially important as you will want to retain the integrity of the original picture.) You can do this quickly using short-cut keys Control-J, or using the menu option, Layer > Duplicate Layer.

Step 2: With the duplicate layer active, select the Lasso Tool from your toolbox. Set a ‘feather’ of 20-25 pixels. You will want a soft edge on the lassoed selection to ensure it blends with the rest of the photo.

Step 3: Using the Lasso Tool, outline the section you’d like to lighten. You do not need to go right around the exact edge of the shape – remember you have a feathered edge. In fact, I’d recommend deliberately going inside the edge to allow for the feathering or ‘bleed’ to help blend the changed section with the original. It certainly does not need to be an exact science here.

Step 4: Open the Levels adjustments (Image > Adjustments > Levels) and slowly move the middle slider, the one that controls the mid-range levels to the left (left increases the light, right adds dark tones). A very light hand is all that’s needed. If you are too heavy-handed, the result will not look natural.

(The shortcut Control-D will remove your selection after you’ve applied the tonal adjustment.)

The resulting change is subtle, but that’s exactly what you want! Here’s my ‘corrected’ photo:

It’s might be hard to see the difference, but the facial features now stand out a little better. There are more highlights in my son’s hair, too, and overall, the face just looks brighter. Here’s a side-by-side for an easier comparison:

Have photos of loved ones wearing baseball caps that cast shadows? Maybe just bad lighting and, as the situation I found myself in, you’re just trying to get any picture that you can. In just a few minutes, you can salvage photos that you might otherwise skim over. But remember, a light hand is all that’s needed; it’s easy to go too far with this technique.

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About the Author Kat Hansen is a creative team member here at The Digital Press. A HR Manager in the real estate industry by day, she loves the opportunity to spend a few hours each evening being creative. Vacation memories feature pretty heavily in Kat’s scrapbooking pages, as well as her health and fitness journey. Kat has quite the sense of humor (she “blames” her father for this), which she incorporates into her journaling and memory-keeping.