.PSB File

File extension psb is associated with Adobe Photoshop's file format for large and oversized images. The JPEG 2000 file format.

In versions of Photoshop prior to Photoshop CS, the maximum image size was 30,000 pixels by 30,000 pixels. That limit still holds for the Photoshop (psd file format).

However, you can now work with images much larger than that. The new maximum pixel dimensions are 300,000x300,000 pixels.

Files over 30,000 pixels in either dimension can be saved as TIFF (up to 4GB, the maximum size the TIFF standard supports) or Photoshop Raw (not to be confused with Camera Raw).

There is also the option of using the new PSB file format - effectively a large-image version of the Photoshop PSD format. You activate the PSB file format capability in the File Handling pane of the Photoshop Preferences dialog box by checking the box Enable Large Document Format (.psb).

If you have a very large image that you need to use with a program other than Photoshop, use TIFF. TIFF supports the maximum image dimensions allowed by Photoshop and file sizes as large as 4GB.

Photoshop will remind you that the PSB file format is compatible only with Photoshop CS or higher versions. Other programs and earlier versions of Photoshop will not recognize the format.

Any file can be saved in the PSB format, but it won't be readable in any program other than Photoshop CS or higher versions.

Notes:
Remember that Photoshop's Large Document Format (PSB) is not available until you enable the feature in the File Handling pane of Photoshop's Preferences dialog box.

Files with psb file extension can be most often encountered as graphics files from Adobe Photoshop. It's a JPEG 2000 based bitmap format for very large images. This format is only compatible with some later editions of Photoshop.

How to open:

You can work with *.psb files in Adobe Photoshop.

How to convert:

Adobe Photoshop and other tools can export or save *.psb files to another format.