An advanced file saving function is a valuable feature of the Digital Sight Camera Control Unit (CCU), which allows the user to rapidly record and save digital images in an efficient and organized manner. By enabling the specification of a set of storage conditions prior to conducting photomicrography sessions, the software automatically records, names, and stores image files as they are captured by the camera system.

Images can be saved in one of two schemes. The first scheme operates by automatically saving each image (after it has been captured and/or digitally enhanced) in a pre-specified folder, under an incrementally numbered filename, and in one of two image file formats. The microscopist can also elect to manually control image saving procedures by individually specifying a folder (directory), filename, and file format, then saving the image. The former method is the most convenient and allows the microscopist to record a large number of images in a single session, while the second method provides greater control over shuffling images through different locations on the CF card or File Transfer Protocol (FTP) server.

The most convenient file saving mechanism involves choosing the folder (directory), filename and format in advance, enabling the operator to save a digital image simply by pressing the Capture button on the CCU or the remote unit, or by clicking the CF or FTP buttons in the REC menu (see Figure 1). The File Settings panel (illustrated in Figure 2) is utilized to specify a folder and filename, as well as a file format, for the digital image. Additionally, these settings can be configured directly from the REC menu for convenience. Photomicrographs captured digitally by the Digital Sight camera system may be saved in one of two different file formats. For low-quality images, choose the JPEG (Joint Photographic Experts Group) format, for which the Digital Sight offers four levels of file compression: fine (highest quality), normal (standard quality), basic (lower quality), and draft (lowest quality).

High-quality files should be saved in BMP (Windows Bitmap) format, which relies on a compression-free algorithm capable of storing files without loss of image information. The JPEG format produces relatively small file sizes and is convenient for images that are destined to be accessed from the Web or transmitted by email or FTP. Use BMP format for high-resolution images where no loss of image detail is acceptable. File sizes range from several hundred kilobytes (KB) for highly compressed JPEG files to over 14 megabytes (MB) for the highest resolution BMP files.

Default file storage settings in the File Settings panel are IMGBOX for the CF card directory (folder), FTPIBOX for the FTP directory, and DSLC#### for the individual image files. Filenames specified in the File Settings panel may start with any character string as a prefix. In addition, the Auto Create checkboxes provide even greater freedom in filename assignment. When the Auto checkbox is selected for the CF card directory or the FTP server directory, the CCU will automatically create a directory whose name is composed of the first two letters of the directory prefix followed by two digits each for the current year, month, and day. Similarly, when the Auto checkbox is enabled for the file name, each captured image will be saved with a unique filename consisting of two digits each for the day, hour, minute, and second when the file was captured.

It is also possible to input a filename manually for the next captured image using the REC menu. When the user clicks on the filename displayed under the File: field, a small keyboard will appear adjacent to the REC menu (Figure 3). The user may then use the graphical keyboard (or a USB keyboard, if it is connected to the CCU) to enter a filename of up to eight characters in length. When the next image is captured, it will be recorded using this filename. After the capture operation has completed, however, the CCU will continue to use whatever naming convention was in effect prior to implementation of the REC menu commands.

If the user attempts to save a file in a folder (directory) under a filename that is identical to a file already stored in the folder, then the CCU will behave differently depending upon which file saving convention is currently being utilized. If the default incremental file naming system is in use, then the CCU will NOT overwrite the existing file, but will instead skip that filename and move on to the next until it finds the first unused filename. If, however, the filename is entered manually by clicking to the right of the File: field under the REC menu, then the CCU will overwrite the existing file without prompting.

In conclusion, when conducting extensive digital photomicrography sessions, the automatic image saving feature is very convenient, because it allows the user to capture a large number of images without the disruption of having to enter individual filenames and directory storage locations.