Resolution and contrast magnification refers to the

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resolution and contrastMagnification refers to the increase in apparent size of the image. Resolution or resolvingpower refers to the ability to distinguish fine detailContrast refers to the ability to distinguish objects such as cells, from the backgroundOptimizing these three factors will produce the highest quality image Contrast is enhanced by staining Define contrastMost cells have no pigment and blend in with the backgroundBy staining either the cells or the background, the contrast is improved and it is easier to see the bacteriaIt is also possible to increase the contrast by changing the amount of light that is passing through the sample from the lampResolution: the ability to discriminate two points as separate Define resolutionResolving power or resolution is the ability to distinguish two closely spaced objects in a microscope fieldIn the diagram, the samples on the top cannot be distinguished when close together so they cannot be resolved. In the bottom part, it is possible to see there are pairs of organisms so your eye is resolving them Magnification: using lenses to increase the size of the image Define magnification
Magnification refers to the apparent increase in size of an object viewed through the microscope. This is accomplished by viewing an object through a combination of glass lensesParts of the microscope Identify the different components of a microscope These are the ocular lenses or eyepieces, which provide 10-fold magnification. They can be adjusted to fit the distance between the user’s eyesThe objective lenses are located on this structure, the revolving nosepiece. Each one provides a different level of magnificationThis is the stage of the microscope on which slides will be clipped into place for viewing.The stage adjustment knobs control the movement of the stage to bring different parts of a slide into view. One knob enables movement of the stage, forward and backward. The other knob moves the stage to the left and to the rightThese are the focusing knobs. This larger knob is the coarse focus knob, which is used only when focusing with the lower power lenses. The smaller is the fine focus knob. This is the only focus knob used when the high power of oil immersion lens is being used The condenser is a lens that adjusts the light to improve contrast of the image Video-care of the instrumentRecall how to handle the microscope When carrying the microscope, it should always be supported with two hands. One hand holds the arm of the microscope and the other is placed under the base of the microscopeBefore returning the microscope to its cabinet, the 4X (scanning) lens should be rotated into place over the stageFunctions of microscope componentsDescribe the function of each of the components of the brightfield microscope These eyepieces contain ocular lenses that magnify the specimen by a factor of 10.

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