Images can make or break a book's design and reader experience. However, optimizing images for both print and digital formats requires careful consideration to balance visual impact and file size. Here are my tips for effectively optimizing book images.
Choosing the Right Image Format
The image format significantly impacts file size and quality. For print, high-resolution TIFF or PNG files are best to retain crisp detail at large printed sizes. For ebooks and websites, smaller JPEG or compressed PNG files are preferable to keep file sizes manageable.
Image Dimensions and Resolution
Print resolution should be 300 dpi at the intended display size to look sharp. Web and ebook images only need 72 dpi at the pixel dimensions displayed. Larger images should be scaled down in editing software, not just with HTML/CSS which degrades quality.
Compression and Optimization
Lossless compression like PNG or TIFF reduces file size with no quality loss. Lossy JPEG compression allows adjustable quality/file size trade-offs. Run optimization software like ImageOptim on final files. Cropping to subject also shrinks files.
File Naming and Alt Text
Descriptive file names and alt text boost SEO and accessibility. Name files and alt text based on the main subject and purpose, like "cover.jpg" and "alt=Book cover with title and author name".
Balancing Print and Digital Needs
With careful formatting choices, one set of high-quality image files can work for both print and digital. Optimize files for the best print quality needed, then export/compress additional digital versions. Technical skill and testing is needed to find the sweet spot between quality and file size for each project.
By following these tips on image formats, resolution, compression, naming, alt text and balancing print/digital needs, you can effectively optimize images for books across formats. Efficient image files enhance design and reading enjoyment while reducing file size. With practice, you can master image optimization for great book design in both print and ebook formats.