One of the most misunderstood parts of digital photography is what happens after you take the shot: the post-processing. This is where you edit the images you have taken, to create the final product.
Post-processing is the equivalent of the darkroom from the days we shot in film.
In today’s post we’re going to be covering some ideas for post-processing, from the basics (cropping and leveling), through to more complicated actions like recovering shadow and highlight information.
Before we get into editing, let’s start by taking a look at some different file formats and software options for post-processing — on both mobile phones and computers — and then dive into some real-world examples.
File formats
Every single photo that is taken is digitally edited in some way. When you press the shutter button, the camera saves the image data onto your memory card. If you’re shooting in RAW, the camera records just the image data onto the memory card, meaning that you are going to have to “develop” it yourself. Think of a RAW file as a roll of film — you can get images from it if you develop it, but you can’t flick through the images as they are.
If you’re shooting in JPG, then the camera will process the image for you, based on pre-defined profiles. Your camera will let you define these profiles — changing things like contrast, saturation, and sharpness, and will apply them to the JPG.
This is why I always recommend shooting in RAW — it’s more work after the fact, but it puts you firmly in control of the image editing process, rather than letting your camera make all the decisions for you. RAW files also contain a lot more data about the image, giving you much more control over your finished image.
Here is a list of the best editing tools out there:
Adobe Lightroom (PC or Mac) –Lightroom is the industry standard tool for photography professionals. But this post is not going to focus on Lightroom, nor cover everything you can do in Lightroom, as it’s a massively complex tool, covering both photo management and photo editing.
iPhoto (Mac) – I list iPhoto here mainly because it’s a commonly used tool among Apple users. However, I personally never recommend using it. While it will let you do everything that I cover in this post and is better than nothing, the way it manages your photos makes it hard to migrate to a more sophisticated system further down the line if you choose to do so.
Picasa (PC or Mac) – Picasa is a free desktop photo editing application from Google. It’s very simple, but it allows you to do everything I’m going to cover in today’s post. If Lightroom is a bit overwhelming, Picasa is a great, free place to start.
Snapseed (iOS or Android) – Another free Google tool, Snapseed is the best mobile image-editing app for both iOS and Android. It’s an incredibly powerful tool that, while simple to start using, has a great many features that take time to fully master. I use it for 95% of my mobile editing needs.
Let’s take a look now at what you can and should be using these tools for with your images.
Editing photos
1. Cropping
The crop tool allows you to change the size of your image, and also to change the aspect ratio. For example, you can crop an image from a rectangular shape to a square shape. There are many reasons you would want to crop, including for publishing in different formats and aspect ratios.
Let’s take a look at the first photo from this post, a lightning shot I took on a recent trip to the Florida Keys. Here’s the original version without cropping:
And the edited version, post-crop:
Compared to the original, I have cropped the image to remove the dark part of pier on the right-hand side of the image, and recomposed using the rule of thirds, so I have one-third land and two-thirds sky. This makes the lightning bolt more the focus of the shot.
You might wonder why I didn’t just compose properly when taking the shot. Well, in this case, I was doing a long-exposure shot without a tripod, so had the camera balanced on the edge of the pier for stability. That very much limited my ability to perfectly frame the moment, so I just shot wider, knowing I’d be able to crop the shot appropriately after the fact.
Let’s look at what cropping looks inside a couple of the tools available.
Here’s an example of cropping in Snapseed:
And the same thing in Lightroom:
In both cases, cropping is very simple: it just involves you selecting the crop tool and then selecting the area you want to keep with your mouse or finger. Then you apply the changes, and voilà , your new cropped image is ready to go.
As you see from this and later examples, the tools look similar across different platforms, so it’s easy to apply the learning you have from one tool to another.
2. Leveling
One of my personal petty annoyances in photography is when the horizon line in a photo isn’t level. Sometimes when we’re caught up in the moment, this basic compositional rule is forgotten — but the good news is that editing a photo to make it level is also very easy.
I’ll use the lightning shot as my example again. Balancing the camera on the edge of the pier meant that the shot wasn’t level — this is particularly noticeable to the eye when the image has a clearly defined horizon line, such as the sea.
If we look at a zoomed in version of the image in its original form, with a line overlaid near the horizon, we can see that it’s not level — the line is closer to the horizon on the right-hand side than the left.
In Lightroom, the level tool is part of the crop tool, and you can just rotate the image to suit. When you use the level tool, a grid will appear to help you get the alignment correct. Here’s a screenshot of that in action in Lightroom.
And here’s the same procedure in Snapseed, where the level tool is called “Rotate”:
Leveling an image is a really simple task that will take just a few seconds of your time, resulting in a much more visually pleasing image.
3. Vignetting
Vignetting is about making parts of the image darker or lighter than other parts, in order to make it clearer what the subject of the shot is.
Some tools restrict your vignette to the corners, but in applications like Snapseed and Lightroom you can selectively darken and lighten areas of the image — you don’t need to restrict yourself to the corners.
Taking the lightning shot above, let’s load up the vignette tool in Snapseed.
Here we have options for how big to make the “center size,” i.e., the area to be edited. Inside this area, everything can be made brighter (inner brightness) and everything outside the area can be made darker (outer brightness). We can also do it in reverse, making the inner darker and the outer brighter.
Let’s apply the vignette tool to the lightning bolt, to give you an idea of the effect:
Above are the settings I chose for outer brightness and inner brightness, while below is the size of the vignette itself, which is based on the center size setting.
Vignetting is particularly good for portraits, and anywhere where you really want to make the subject of the image more clearly obvious to the viewer.
4. Shadows and Highlights
Sometimes when we take a photograph, parts of the shot might end up being darker or brighter than we want. We refer to the dark areas of the shot as shadows, and the bright areas of the shot as highlights.
We can fix this by changing the brightness of the shadow and highlight areas specifically, using either the “Shadow” or “Highlight” tool. This is a tool that works particularly well on RAW files as they retain more information on the shadow and highlight areas of an image compared to a compressed JPG, which discards most of this information in order to save file size.
Let’s take a quick look at adjusting shadows and highlights using Lightroom. In Snapseed, shadow and highlight adjustment can be found under the “Tune Image” setting.
Here’s a shot of a couple enjoying a bonfire and fireworks display in Edinburgh during Hogmanay:
As you can see, the fireworks and bonfire are clearly visible, as are the torches the couple are holding, but the rest of the shot is dark. Let’s adjust the settings and see what we can get.
In this version of the image the couple is much more visible, as are the hill the fireworks are on and the surrounding crowd.
To achieve this I increased the overall exposure of the image, making the whole image brighter, including the shadows and the highlights.
Then, as the shadow areas were still a little dark, I increased those a little more.
Finally, as the global exposure adjustment made the fireworks and bonfire too bright, I reduced the highlights a little bit to give the final result.
Shadow and highlight adjustment is useful in a wide range of scenarios to help balance the image out — bringing overexposed areas down in brightness, and helping to boost the shadows. Just be aware that a light touch is recommended — increasing the brightness of the shadows too much can result in a lot of noise being revealed, which might look unnaturally green or purple.
5. Adjust the Contrast
Contrast is about accentuating the difference between the light and dark parts of the image. Increasing the contrast of an image can dramatically improve the visual impact that is has, by making the boundaries between those light and dark parts clearer.
Let’s take a look at a shot of people jumping against the sunset in the Sahara, for example, which I’ll be editing in Snapseed.
There is nothing too wrong with this shot, but it lacks the visual impact that I wanted. Ideally, I would want the shapes of the people to be in full silhouette against the sun, but as it was shot the camera picked up some skin tones and clothing color.
Using the contrast tool, we can make the dark areas stand out against the bright areas.
And here’s the result:
As you can see, this made the jumping figures and the dune more silhouetted against the sky. In most shots, you only want to tweak the contrast a little bit to get the desired effect, normally no more than +20 or so, but in this case the higher number gave the best result.
6. Colors
Color adjustment is another important piece of the editing toolkit. We can adjust image color in all sorts of ways, from changing the overall “warmth” of the image (how blue or yellow it appears), to individually changing the hue and saturation of specific colors inside an image.
For this post, though, I just want to cover some very simple color changes you can use to make your images just a little more visually impactful.
The fastest way to adjust an image’s color is with the “Saturation” tool. This changes the appearance of every color in an image to make it more or less saturated. We can use the saturation tool to desaturate an image, eventually resulting in a black-and-white image with no color:
Or we can go all the way to the other end of the spectrum, and make the color incredibly saturated:
As with many edits, the key is to find a good balance — oversaturated images tend to look rather unnatural. Desaturated images can be very effective, and of course black-and-white is an excellent choice for all sorts of situations, in particular, portraits, architecture, and certain landscape scenes. But generally you would want to find a happy midpoint: not too oversaturated and not too undersaturated.
Saturation is adjusted on a sliding scale and is on the basic adjustments panel in Lightroom, or the “Tune Image” option in Snapseed.
7. Blemish correction
The last area I’m going to touch on today is blemish correction, or “image healing.” Sometimes there will be something in an image that you really don’t want to be there, like an inconvenient pimple on someone’s face. This is easy to remove in all the major editing tools.
You can, in theory, remove any object from a scene, but the healing tool works best on distinct, small objects that are surrounded by uniform colors. This is because the heal tool has to replace the area you wish to remove with something else, and this works best when it has an area nearby that looks similar. So for example, a pimple on a face is surrounded by a lot of similarly colored skin, so the heal tool can easily calculate what to replace the pimple with based on the surrounding area.
For this example, I’m going to show how Snapseed can be used to replace an object in a scene. Here’s a group of people sitting on a sand dune in the Sahara:
Let’s say for some reason I only wanted to have people sitting in my shot, and I need to remove the standing person. She is a good candidate for removal as she is separate from the rest, and the surrounding scenery is not too complicated.
In Snapseed, we load up the healingtool, then we zoom in on the object to be removed with the standard “pinch to zoom” gesture.
Next, we use our finger to draw the area to be removed. It’s important to be as precise as possible, because the tool is most accurate with small objects.
Once we have drawn the area, Snapseed will edit it out, replacing it with a best guess of what is behind the object.
As you can see, the result is impressive, with no real evidence that there was anyone standing there at all.
The healing tool is perfect for all manner of fixes, from editing out unwanted background strangers in your shot, to removing skin blemishes in portraits or power lines in landscape shots.
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