OK, I admit it: We wrote this title because my original one was extremely unprovocative:
Basic 4-step Photo Post-Processing
Rita thinks that’s about as sexy as Alice.
Image from http://www.tvacres.com/char_nelson_alice.htm
If there is anything sexy in this post, it’s sexy in the way Alice is. It’s a little plain Jane on the surface, but more here than meets the eye.
Like Alice, our process gets the job done and is more fun than you might think.
In that spirit, we want to share with you 4 steps for editing photos that’s got a nice balance between ease of use and complexity of control. It’s what I teach high school students as a starting point–but it’s the same process I use, too.
If you’ve been wondering how to take your photos from OK to awesome, here’s how it works:
Choose a photo editor
You’ve got to do this before you start. For this post, I’ll be using an online editor called Pixlr. I like it because it’s very similar to Photoshop, and if you move on to Photoshop later you will already know some basics of how to use it to edit photos. Pixlr is a great way to get your feet wet if you think you might want to use Photoshop (and most serious photographers do).
This is the image I’m going to edit (taken in an empty lot just a few blocks from our house). If you want, you can download it and follow along as I go. (Just right click> save as…)
1. Adjust exposure
Exposure is simply a measure of lights and darks in the image. It’s important to start with exposure adjustments first because the 3 adjustments we’ll do after are all affected by exposure.
When examining exposure you should look at the darkest and the lightest parts of the image. Look for details in these areas. If there is good detail in the dark areas then the image is well exposed for shadows. If there is detail in the highlight areas then the image is well exposed for highlights.
Sometimes I’ll find after fiddling around with exposure that it was just fine right out of the camera. Usually I’ll have to fiddle with it a bit to make sure.
If the dark areas turn into a dark mass with no detail then the image is underexposed. If the light areas are a white blob with no details then it’s overexposed and the highlights are said to be blown out.
To adjust exposure we need to ask ourselves a few questions:
- Is the image too dark overall?
- Is the image too light overall?
- Is there detail in the highlights?
- Is there detail in the shadow areas?
- Is the image too contrasty? (the lights are too light and the darks too dark)
- Is the image not contrasty enough?
Here are my answers to the questions for our image:
- Is the image too dark overall? Yes, the highlights look OK but the rest of the image is a bit dark.
- Is the image too light overall? No.
- Is there detail in the highlights? Yes, good detail in the highlight areas.
- Is there detail in the shadow areas? No, shadow areas are dark blobs.
- Is the image too contrasty? No
- Is the image not contrasty enough? No
We are now ready to start adjusting exposure. There are several different ways of doing this. I picked a method that gives the best balance between ease of use and versatility of adjustment. We’ll use a levels adjustment.
After moving the mid tone adjuster a bit I found that the image looked way better. If I went too far with the adjustment I started to lose detail in the highlight area so I made sure to balance as best I could both highlight and shadow adjustment. You can try moving the highlight and shadow adjusters as well to see what effect they have on the image. Pixlr will preview it right away for you.
Here’s the adjustment I liked best for my image:
If you want to increase contrast you move the adjusters closer together. In our case the contrast was fine so we’ll leave that alone. We are now ready to move on to our next adjustment: Color
2. Adjust color
After the exposure is corrected you can better see the color in the image. Our digital cameras will attempt to adjust color as we take pictures under different types of light. Some light sources are cooler and some are warmer. The camera usually does a pretty good job of getting it right, but sometimes the images need just a bit of adjustment.
There are just two questions we need to ask before we start adjusting color:
- Is the overall color of the image too cool? (bluish)
- Is the overall color of the image too warm? (reddish)
In our case I think the image is a bit too cool. The color isn’t bad but I think the image would look a bit better if I warmed up the tones a bit. We’ll use a color balance adjustment to get the effect we want.
Go to Adjustment>Color balance. At this point you simply move the sliders until the image looks right. It will add or subtract red, green, and blue in the image depending on which way you move the slider.
Pixlr gives you immediate preview so you can see right away how the adjustment will affect the image. Here are the settings I used. I warmed the image up a bit by adding some red. I also boosted the blue a bit and the green just a touch.
Now that the color is adjusted properly we’ll work on doing a bit of sharpening.
Sometimes images come out of the camera slightly unsharp. Unsharpness is different than blur. Blur is permanent and can’t really be adjusted. Unsharpness is a slight fuzzyness to edges that are characteristic of digital cameras.
Sharpening of an image is a process where the software will find edges in your image and increase their contrast. The darker edge will get darker and the lighter edge will get lighter. You have control over 3 things when increasing edge contrast.
- Amount– How much should we turn up the contrast?
- Radius– How far out from the edge should we go in increasing contrast?
- Threshold– How contrasty does an edge have to be before we call it an edge?
Before we sharpen our image we need to zoom all the way in to 100%. You must be zoomed all the way in to see the actual effects of the Unsharp Mask as you are making adjustments.
In Pixlr go to Filter>Unsharp Mask. This will bring up or Unsharp filter.
I scrolled over to an area of the image that has some fine detail so I could more easily see the results of sharpening. What we are looking for is a subtle effect. Edges should look slightly sharper. If you go to far it will introduce grainyness and unwanted pixels all over your image. Mostly you want to keep the radius and threshold fairly low and move the amount slider back and forth until it looks right. Often you’ll have to move it back and forth a bit to see what works best.
Here’s a look at the image with too much sharpening applied. There are white pixels all over the image that look horrible.
Sharpening should be subtle. It won’t make a dramatic impact on your image. If you have a light hand with sharpening you’ll make some subtle improvement in your image without causing problems shown above. Now we are ready to crop.
Here’s a bit closer look at sharpening with some examples at different settings. I don’t think my original post explained it well enough. We’ll only adjust the amount slider and leave the radius and threshold the same in all images. (radius 2 and threshold 3)
We’ll start with a low level of sharpening and move up a bit at a time so you can see the results.
Let’s take a look at a different part of the image. The first shot will have too much sharpening applied. You’ll be able to see sharpening artifacts that happen when you go overboard. The second will be the image before sharpening so that you can see what that area looked like before we sharpened it.
Final before and after. I ended up using an amount of 60 for this image. I found that sharpening any more than that didn’t give me a much sharper image and it started to cause nasty artifacts to appear.
Cropping is not always necessary. Sometimes images are perfectly composed right out of the camera. I often find,though, that most images can be improved by a small amount of cropping. The common error in photo composition is to zoom a bit too far out when taking pictures. Cropping images tighter will usually allow us to focus more on the main subject in a photo.
Some people crop their images first thing. I prefer to wait until I have the image looking good before I crop it. That way I can see how it looks with all the color and exposure adjustments etc. done as I crop the image. You could crop first if that’s not a concern.
To crop look for the crop tool in the tool bar. Click on it and set the constrain to Aspect Ratio. This will let you set the height and width to match the size you will print the photo. I picked 8 x 10 so I can get good 8 x 10 prints.
Below you will see the crop I picked. I cropped out a drainage culvert on the left hand side and cut down the sky area a bit. I like this composition better than what came right out of the camera.
And that’s it.
This is the basic 4 step post processing, and it’s one you can use with any photo editor (not just Pixlr).
Here’s my image after applying all of them:
I liked the edited image much better than the original, but the more I sat with it the more the sky seemed not quite right. It was a bit pinkish, so I went through the process again. One nice thing about the process is that you can try it a few times. Each time you’ll get a bit better at it and improve your results.
Putting it to use
This 4-step process is one we use all the time. We used it when creating prints for the zipline photo gallery we shared earlier this week, and what we do for many of the images we put in our posts. It’s not going to save a photo that’s blurry, way over- or under-exposed, or has some kind of compositional weirdness you just can’t do anything about.
Luckily, the other beauty of digital is that you can take lots and lots of photos. Chances are, you’ll have plenty that can be saved with the few quick adjustments.
And in case you’re wondering about Friday Food…
Rita wants you to know that it’s not on permanent hiatus. For her, making her way through the school year is a little like running a long-distance race. She gets into a steady, even groove for the middle of it, but there’s a kick at the end. Right now, the end is kicking her.
There might be a Saturday edition of Friday Food…but there might not. If you’re a subscriber or follower, it’ll be up in the usual places if there is one.
If you’ve got any great photo editing tips,
we’d love to hear them. Drop us a comment and let us know what works for you.