Enlarging Photos in Photoshop and Maintaining Good Resolution
Have you ever needed to resize a photo and while making it larger, it became pixelated?
If you take a look at our tutorial on A Lesson in Resolution, you’ll see what that looks like.
The preferred resolution for printing a photo is 300dpi or higher. You may have a photo that is too small to be used at the size you want. There are ways to enlarge a photo without losing the photo’s quality. Below are a few ways to achieve this using Photoshop.
We’ll be working with this image as an example.
1. Resampling by 10%
One way you can enlarge your image while maintaining good quality is by resampling the image using the Preserve Details option.
• Open your image in Photoshop.
• Click on Image > Image Size from the menu at the top of the screen
• In the Pixel Dimensions setting, use the dropdown to select Percent (see screenshot below).
• To resize the image by 10%, change the width/height to 110 from 100 percent.
• Below that, in the Resample dropdown, choose Preserve Details (enlargement).
• Set the Reduce Noise bar to 10% or so
• Click OK and the image will be increased by 10%.
You can do this in 10% increments to gradually see how the image quality changes or increase by more than 10% to reach the desired size.
See the original photo (left) and the larger version (right).
Once you have resized your image, it might appear blurry. You can sharpen the image in a few different ways.
• Click on Filter > Sharpen from the menu at the top of the screen
• Select the Unsharp Mask filter
Use the sliders to control the following:
• Amount – This determines how light the lighter pixels get, and how dark the darker pixels get. If you set the amount too high, your picture might look grainy and become too contrasty, and you’ll actually lose some fine detail.
• Radius – This determines the area that will be sharpened. A low radius means only the pixels close to the edges will be sharpened. A high radius means a wider area will be sharpened and
• Threshold – Your choices range from brightness values of 0 to 255. Selecting a low value emphasizes edges with very little contrast difference, which is usually what you want. There is no correct formula for this. It all depends on the type of photo you are using and how sharp you want the photo to be (See screenshot below).
• Click OK when you are done.
The controls provided by this filter make it the best choice for sharpening. Although Photoshop also has the Sharpen, Sharpen Edges, and Sharpen More filter options, these filters are automatic and do not provide controls and options.
3. Reduce Noise
Noise is like grain found in film photographs. It can look like splotches of discoloration and it tends to become more apparent when enlarging a photo. To reduce the amount of noise in your photo, follow the steps below.
• Click on Filter > Noise > Reduce Noise
Here the options are:
• Strength – Specify the amount of noise reduction,
• Preserve Detail – A higher number preserves edges and details but reduces the amount of noise removal. Find a happy medium.
• Reduce Color Noise – Removes random colored pixel artifacts like red, green and blue spots and
• Sharpen Detail – Keeps the image from becoming too blurry from noise reduction.
Experiment with moving the sliders to see which works best and achieves the desired effect.
Note that if you are using your image in a backdrop or a super sized tradeshow banner, then it’s acceptable for the DPI (resolution) to be reduced to 150 instead of the ideal 300. However, always check with your printer as different printers have their own guidelines.
Hopefully your new resized image is looking fantastic!