The enhancement settings panel, available as a tabbed dialog box through the Retouch Image window panel tab header, is utilized to adjust the brightness, contrast, gamma, and sharpness of digital images captured with the DXM 1200 camera system.

Figure 1 illustrates a series of digital images that have been retouched using the enhancement settings panel. The specimen is a recrystallized preparation of biotin (vitamin H), that has formed spherulites from a melt preparation sandwiched between a microscope coverslip and slide. After the crystals have completely melted, the coverslip is pressed firmly onto the microscope slide to reduce the thickness and to help form a confluent layer of crystallites upon cooling. This vitamin forms beautiful large spherulitic crystals that grow radially from a central nucleation point. The usually round spherulite structures stop growing when they encounter the crystal front of an adjacent spherulite.

Presented in Figure 1(a) is a digital image of the biotin specimen that has been underexposed and is slightly out of focus. In many cases, especially with the observation of dynamic specimens, the microscopist is unable to reproduce photomicrographs and must rely on digitally retouching faulty images captured with the microscope. This example was chosen to demonstrate the efficiency of the enhancement settings panel in performing the retouching maneuver.

The dark biotin image (Figure 1(a)) was loaded into the ACT-1 Retouch Image window and the Enhancement settings panel (Figure 2) tab selected. Using either the brightness slider or the text input box, the brightness level is increased to a value of 100 units (Figure 1(b)). Next, the contrast slider is moved to the right to add contrast to the image (Figure 1(c)). Finally, the sharpness slider is adjusted to produce a crisp, sharp image (Figure 1(d)). Gamma correction was not performed on this specimen, but (if employed) would serve to darken or lighten many portions of the image.

The dramatic improvement in image quality produced by the Enhancement settings panel (Figure 2) is evident by comparing Figure 1(a) and Figure 1(d). After the each adjustment is made to the digital image, the Apply button is clicked to apply that change to the image stored in the ACT-1 software window. If several adjustments are made (for example, brightness and contrast) that collectively appear unsatisfactory, click on the Reset button located at the bottom of the settings panel to cancel all of the correction factors made to the image.

	Interactive Java Tutorial
Retouch Image Window Explore the various features available in the DXM 1200 ACT-1 image correction and retouching software. Included are algorithms for brightness, contrast, color correction, cropping, and resizing images.

When the image meets approval, click on the OK button located at the bottom of the Retouch Image window to apply the changes and return to the ACT-1 software window. The image should then be saved with a different name by the Save As command line from the File main menu. If one of the correction factors is changed and the user switches to another settings panel, the Retouch Image dialog box (not illustrated) appears to question whether or not to apply the update. Clicking on the OK button will apply the changes, while clicking on the Cancel button in this dialog box will cancel the latest corrections. Note that clicking on the Apply button in any Retouch Image settings panel will apply the changes and reset the correction factors back to zero.

Although the image correction utilities offered in the ACT-1 control software Retouch Image feature are not as fully developed as those found in high-end image editors such as Adobe Photoshop, the algorithms for brightness, contrast, image sharpness appear to work in a satisfactory manner. We recommend the application of more sophisticated image editors for critical work, but for routine microscopy, the Enhancement settings panel will produce acceptable images.