Introduction - TWAIN

EFS-1 uses a TWAIN interface to transfer images to your computer. The EFS-1 software is a TWAIN Data Source.

TWAIN is an industry standard. The TWAIN initiative was originally launched in 1992 by industry vendors who recognized a need for a standard software protocol and applications programming interface (API) that regulates communication between software applications and imaging devices (the source of the data). TWAIN defines that standard.

The three key elements in TWAIN are:

1. The application software
2. The Source Manager software, and
3. The Data Source software

For EFS-1:

• The included application software is Adobe Photoshop Elements
• The Source Manager is a component of the Windows Operating System
• The Data Source (the UI) is software that is unique to EFS-1 (and described in this manual.)

What is TWAIN?

Note: EFS-1 is TWAIN, but not WIA compliant.

You may elect to use EFS-1 with any TWAIN-aware application. Photoshop is included with the EFS-1, because it is an excellent imaging application, but it is not required. If you already own another TWAIN-aware imaging application you may prefer to use it instead.

The EFS-1 UI/DS is unique in that allows you to interface with the EFS-1 hardware and take full advantage of the features of the EFS-1. The EFS-1 UI/DS provides additional capability. Unlike most TWAIN data sources, the EFS-1 UI/DS also serves as a stand-alone Windows application without the assistance of a TWAIN-aware imaging application.

The EFS-1 UI/DS has two modes:

• TWAIN Data Source Mode
• Stand-Alone (Shell) Mode

Both modes are described in the following sections.

TWAIN Data Source Mode -

Which Applications are TWAIN aware?

There are literally hundreds of TWAIN-aware applications. It is almost safe to assume that any application that is photographic or image oriented is TWAIN-aware. To check to see if an application program is TWAIN aware, start the program and examine the File and Edit menus for key words including -

• Acquire
• Select Source
• Import
• Scan
• Get
• Twain_32

Despite the fact that TWAIN is an industry standard, the specific steps (menu selections) that are used to "call" a TWAIN Data Source are not standardized. The steps vary from application to application.

Several specific examples are provided in the subsequent sections including -

• Adobe Photoshop Elements
• Adobe Photoshop 6
• Kodak Imaging
• Microsoft Office 2000 Applications

Stand-Alone Mode Application (Shell Mode):

Stand-Alone Versus Called. In the Shell-mode the User Interface/Data Source offers the same functionality as the TWAIN data source mode with one exception. In the Shell mode, you cannot transfer an image to an application. Since the UI is running in stand-alone mode it was not "called" from a TWAIN-aware application. Since the UI/DS was not called, there is no calling Application to which the image may be transferred.

Transfers are not available in stand-alone mode. Therefore, both the Transfer button and the Transfer to App sub menu will be grayed-out and unavailable. This is true even if a TWAIN aware application is presently running on your computer. The EFS-1 UI/DS will only transfer an image to a "calling" application.

Advantages of Stand-Alone Mode.

Since transfer functionality is not available, what are the advantages of Shell mode? When would you use this mode?

There are actually many situations when stand-alone mode is very useful:

• Faster Operation. In the stand-alone mode you do not need to first launch a TWAIN-aware application, and then initiate a call to the EFS-1 data source. In stand-alone mode you simply launch the EFS-1 shell application and begin downloading or processing images.

• System Requirements are Reduced. If your computer has limited resources (processor speed and RAM) you may wish to download images in stand-alone mode, convert images to a common image file format, and then work on those images in a secondary operation. This reduces the concurrent demands upon your computer for download, memory transfer and image manipulation.

• Quick-Cycling of (e)film. Stand-alone mode offers simple, quick download of images in a situation which you need to unload images and begin shooting again.

• Simplified Batch Processing. Stand-alone mode offers the simplified ability to batch process digital negatives to JPG, BMP, or TIF in a manner that is much easier than transferring your images to an application and then processing them individually , or in batch process.

• Name Retention in Batch Processing. The EFS-1 UI/DS allows you to rename images in real-time while you review them in the UI workspace. If you rename your images and then batch process them from DNG to JPG, BMP, or TIF -- the files names (the prefix before the extension) are preserved. This can be a tremendous help with image file management and a significant time-saver.

• Viewer for Digital Negatives. The EFS-1 UI/DS is a quick and convenient "thumbnail-viewer" to look at your DNG files. To take a quick look at a digital negative, there is no need to launch an imaging application and then call the EFS-1 UI/DS. This is useful for image file management.

• Color Science Adjustments. The EFS-1 UI/DS includes the ability to adjust some of the color science applied to a digital negative. For example, if you wish to remove sharpening from an image, you can do this in the UI and then save the unsurpassed image as a JPG, BMP, or TIF. For more information on this subject see the section on Advanced Features in Image Processing.)

The word TWAIN is from Kipling's "The Ballad of East and West" - "...and never the twain shall meet...", reflecting the difficulty, at the time, of connecting scanners and personal computers. It was up-cased to TWAIN to make it more distinctive. This led people to believe it was an acronym, and then to a contest to come up with an expansion. None were selected, but the entry "Technology Without An Interesting Name" continues to haunt the standard. "