Colored image, optical density

The data can be visualized in several formats. In a gel image, the optical density at each point is related to the fluorescence intensity false color images can be used to improve the dynamic range of visualization. We usually employ a logarithmic compression to help visualize the wide dynamic range of the data the image can be processed to saturate the most intense components, allowing observation of less intense components. 

The image is usually formed via photoelectrochemical deposition of metals (Pd, Ag, etc.). Metallic particles either directly form the image of a sufficient optical density (Goryachev et al, 1970, 1972) or serve as nuclei of crystallization in the course of development (Kelly and Vondeling, 1975). Photoelectrochemical reactions of colored organic compounds may also be employed for producing image (see, for example, Reichman et al, 1980). 

Recently, an automatic color video image analysis system was developed to quantify antigen expression (androgen receptor) (Kim et al.,T999a). This system provides a linear relationship between the antigen content and mean optical density of the immunoperoxidase-substrate reaction product. Titration of antibody, concentration, and reaction duration of the substrate can be optimized with this system. The imaging hardware consists of a Zeiss microscope, a three-chip charge-coupled-device camera, a camera control board, and a Pentium-based personal computer. 

Generating vibrant images on paper is one of the primary goals of printing. A parameter used to quantify the darkness of prints is the optical density, OD = — log (7/7o), where lo is the intensity of incident light on a print, and I is the intensity of hght reflected from a print. Alternatively, color coordinates such as L, a, b are also used to quantify color prints, where L is the luminance (lower L darker),... 

Fig. 16. Signals obtained using a streak camera, (a) Image obtained from the streak camera measurements (1024 x 1344 pixels) where each pixel indicates the value of the optical density at the corresponding time and wavelength (in false colors, increasing absorbance from blue to red), (b) Spectrum measured 65 ps after the electron pulse, (c) Kinetic profile at 570 5 nm.

Measurement of optical density of colored image. Macbeth densitometer was used for measurement of transmittance density. 

Figure 4 is the computer image of the 96-well microtiter plate. Each well is illustrated as a circle, and the thickness of the line used to draw the circle graphically displays the measured optical density in the wells. In the experiment illustrated, rows of weUs "A" and "H" were unused and are blmk. For each individual row, wells 3 through 10 illustrate a two-fold serial dilution of competitor. Wells in columns 1 and 2 for rows "B" through "G" are controls where the MelQx-albumin was omitted. The absence of color in these wells demonstrates the lack of non-specific binding of the anti-MelQx and peroxidase-anti-mouse antibodies, and defines experimentally "complete inhibition" for the competitive ELISA. Wells "Bll" through "G12" define the other extreme experimental condition, that of no inhibition. In these wells, no competitor was added and all of die anti-MelQx antibody was available to bind to the solid phase. 

Color Plate 3 Dual-channel imaging technique. Bacterial cells were grown in synthetic medium without nitrate to an optical density at 500 nm (OD500) of 0.5. The proteins were labeled with [ S]-L-methionine 20 min after transfer to anaerobic conditions. Protein extracts were separated on 2D gels. The resulting images from the protein synthesis... 

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