Saving images

The saving options vary between Photoshop and ImageReady. The primary focus of ImageReady is producing images for the Web. If ImageReady doesn't provide the file format or option you need, you can edit in Photoshop. For more information on saving an image for the Web, see About optimization and Optimizing images.
To preserve all the Photoshop features in your edited image (layers, effects, masks, styles, and so forth), it's best to save a copy of your image in Photoshop format (PSD). (See Photoshop format (PSD).) Like most file formats, PSD can only support files up to 2 GB in size. In Photoshop, if you are working with documents larger than 2 GB in file size, you can save your image in the new Large Document Format (PSB), Photoshop Raw (flattened image only), and TIFF (up to 4 GB in size only). For more information on saving large documents, see Saving large documents (Photoshop).