How to batch compress images in Photoshop for faster printing
This User Guide will help you to compress batches of images. This is particularly useful if you intend to send multiple high-resolution images to print as part of the same print job – eg as a contact sheet. Combining multiple large images into one print job can generate a large file; the larger the file, the more slowly it will print on the GSA Library MFDs (printers/photocopiers).
Before you begin, create a folder containing all of the images that you wish to compress.
Open Adobe Photoshop, then click File > Scripts > Image Processor
You will see the following window. Under Select the images to process, click Select Folder then navigate to and select the image folder that you just created.
Photoshop will create a new folder in the original location, in which to save the compressed images. To change the destination, under Select location to save processed images, check the box and click Select Folder.
In the File Type section, you can adjust settings which will reduce the size of your image files. To print using the GSA MFDs (printers/photocopiers), select Save as JPEG – this will ensure a smaller file size, without a visible reduction in print quality.
- In the Quality field, enter a number between 1 and 12. The lower the number the smaller the file size. Whether or not you notice a reduction in print quality will depend on your original file and the scale at which you are printing. You may wish to test this.
- Check the Resize to fit box and set the maximum width and height for your compressed images.
You will not see any increase in print quality above 300dpi when using GSA Library MFDs. You can therefore calculate appropriate dimensions for your images, and resize them so that they will print at 300dpi at the size at which you require them.
You have a batch of images shot on an 18 megapixel camera, each measuring 5184 x 3456 pixels, which you wish to print as a contact sheet of images each measuring 6 x 4cm.
At 300dpi, the original images would print at approximately 44 x 29cm – around A3 size. For the images to print at 6 x 4cm at 300dpi, they can be resized to just 709 x 472px, making the files significantly smaller without a loss of print quality.
You can use Photoshop’s Image Size function as a tool to help you with calculating such a resize. Open an image, then select Image > Image Size.
Once you have input your settings, click Run. All of the images in your original folder will be processed, and saved to the destination folder that you specified.