The frame thickness of slides and the thickness of film holders can vary slightly, so the scanner optics may not have the optimal distance for scanning. Some professional scanners from Epson, Nikon, Microtek, PIE and Reflecta allow manually adjusting the focus of the scanner optics up or down by a few millimeters. With SilverFast Focus Control, you will receive perfectly crisp sharpness.
What do you do with a Focus Control?
You don’t need a focus control, if your originals really lie perfectly flat on your flatbed. However, using filmholders slightly lifts your originals, slide mounts are of different thicknesses and also filmstrips inserted to film scanners are not always perfectly flat, the focus can vary from frame to frame. Setting an appropriate focus leads to crisp and sharp images.
A flatbed scanner offering a manual focus control may also be used to digitize certain three-dimensional objects like coins. Using SilverFast’s Focus Control, the focus can be adjusted so precisely that flatbed scanners can also be used for scientific work, such as analyzing bird feathers.
Using the Focus Control Feature
AF off: Turns off the Focus Control functionality. Scans are performed without any focus offset, e.g. directly above the flatbed.
AF on: SilverFast automatically sets the focus point to the scan frame’s center. Before starting the final scan, SilverFast adjusts the focus offset automatically after analyzing this center point.
Auto AF point: SilverFast analyzes the scan frame to decide, where the focus point should be placed. Before starting the final scan, SilverFast adjusts the focus offset automatically taking this focus point into account.
Pick AF point: Set the focus point manually. Just left-click inside the actual scan frame at that position you would like the image to be focussed. SilverFast adjusts the focus offset automatically before performing the final scan.
Manual Focus: Set the focus point and focus manually. Just left-click inside the actual scan frame at that position you would like the image to be focussed. A Focus Preview dialog will open and SilverFast starts a prescan of that area.
Example: Squash Racket
To illustrate the high performance of our SilverFast Focus Control, a squash racket has been placed directly on the flatbed of the scanner for this example. All details are clearly visible on both the frame and the network of strings.
SilverFast’s depth of field feature and its manual Focus Control enable exceptional scans of 3D objects and thus significantly expand the field of use of scanners that support these features.