How do I stack images on top of each other in Photoshop?

You can stack images on top of each other in Photoshop using the Statistics script to automate the process.

Understanding Image Stacking in Photoshop

Image stacking involves layering multiple images on top of each other to achieve a variety of effects, such as reducing noise, extending depth of field, or creating composite images. Photoshop offers several methods, but the Statistics script is an efficient way to automate this process.

Using the Statistics Script for Image Stacking

Here's how you can use the Statistics script to stack images:

1. Open or Prepare Images:
   • You can either have all your images opened in Photoshop or store them in a folder.
2. Access the Statistics Script:
   • Navigate to File > Scripts > Statistics.
3. Choose a Stack Mode:
   • In the Statistics dialog box, select your desired stacking mode from the Choose Stack Mode menu. Common options include:
     • Mean: Creates an average of all pixels across the stack. Effective for reducing noise.
     • Median: Selects the median pixel value for each location. Good for removing outliers.
     • Maximum: Uses the maximum pixel value for each position. Useful for night sky photography to capture stars.
     • Minimum: Uses the minimum pixel value.
     • Range: Displays the range of pixel values.
     • Standard Deviation: Displays standard deviation of pixel values.
     • Variance: Displays variance of pixel values.
     • Skewness: Displays skewness of pixel values.
     • Kurtosis: Displays kurtosis of pixel values.
4. Apply the Script:
   • Choose how you want the script to gather the images:
     • Apply to Open Files: Choose this option if your images are already opened in Photoshop.
     • Browse: Use this option to select a folder or choose individual files.
5. Run Script
   • After selecting the desired options click OK. The script will then layer all the images accordingly.

Key Steps Summarized

Step	Action
1	Open or gather the images you wish to stack
2	Go to File > Scripts > Statistics
3	Choose a Stack Mode from the dropdown menu
4	Select how you wish to provide the images to the script: Open Files or Browse
5	Click OK to execute the script.

Practical Insights

• The mean stack mode reduces noise by averaging the pixel values, this is particularly helpful for images taken with high ISO settings.
• The median stack mode removes unwanted objects that might appear in only some images.
• The maximum stack mode is great for capturing moving objects like stars.
• Each stack mode creates a unique effect, so experiment with each to find what you need.

By using the Statistics script, you can easily and efficiently stack images in Photoshop for a variety of effects. This method is ideal for reducing noise, extending depth of field, or creating unique composite images.