Double-click the Zoom tool. Type or choose a magnification level of in the Zoom Level box in the application bar. Adjust the view. Fit the page, spread, or pasteboard within the active window. Scroll the view. Do any of the following:. Click the horizontal or vertical scroll bars or drag the scroll box. Press Page Up or Page Down. Turn pages. To go to a parent page, click in the page box at the lower left of the document window.
Or, in the Pages panel, double-click a parent page icon. Work with additional windows. When you reopen the document, only the last-used window appears. To activate a window, click the window tab or title bar. Or, choose the name of the view in the Window menu. Multiple windows for a document are numbered in the order they were created.
Use anti-aliasing for smoothing edges. From the Adjust View Settings menu, choose the view setting for which you want to turn on anti-aliasing. Select Enable Anti-aliasing. Greek type. From the Adjust View Settings menu, choose the view setting for which you want to change the Greek Type setting. You can specify different Greek Type values for each of the view settings. Calculate values in panels and dialog boxes. In a text box that accepts numerical values, do one of the following:.
Press Enter or Return to apply the calculation. Enter values in panels and dialog boxes. Type a value in the box, and then press Enter or Return. Drag the slider. Drag the dial. Widefield eyepieces. These provide a large, bright image and are usually the best choice. They let you see more specimen area than a conventional eyepiece of the same power. This also means that more illumination is gathered and transmitted, providing a brighter image. They should be no more than 15x; 10x is preferred.
In student scopes, they're often fixed in place, which protects against loss, damage, and internal dirt. Fine focus. Desirable, but scarce in the low price range. Focus stop. This will prevent slide or lens breakage.
If the scope doesn't have fine focus this is particularly important. If you can't focus on a very thin specimen paper, or a plastic slide you may have to put the specimen on top of a glass slide. You can tell a lot without test equipment. The rectangular engraved crosshatching around the portrait heads on U. Focus up and down and look for several things:.
A flat focal plane. You can't expect inexpensive lenses to have a perfectly flat field; so-called "plan" lenses are costly. You will, however, find a lot of variation in quality; try to do a side-by-side comparison if you're choosing between two models. You're looking for an image that's really sharp from the center almost to the edge of the field of view, rather than one that must be refocused for each part of the circular field.
Achromatic lenses are highly desirable. This means that the lenses will focus one wavelength usually mid-green, where our eyes are most sensitive well. Uncorrected lenses will show color fringes around specimen detail. Apochromatic lenses, which are corrected for three wavelengths, are too expensive to consider here. No astigmatism. As you go thru the focal point fuzzy-sharp-fuzzy , look for a "linear" image distortion that rotates 90 degrees as you go from above focus to below focus.
This can be caused by an objective lens that isn't round or more common in cheap optics a lens that is tilted in its mount.
Rotate the eyepiece to check for the same problem with that lens. No internal dirt. Defocus the image and look carefully for lens dirt on both objective and eyepiece. Try removing it with gentle use of lens tissue and small amounts of eyeglass lens cleaner. If it's within a multi-element lens, don't buy the scope. Objective alignment. Compound scope three-lens turrets should be reasonably well aligned and the cheaper ones often are not; compare the scopes that you're considering.
Focus on a small centerfield object at the lowest magnification, and then rotate the turret to the next higher power. The chosen object should remain close enough to center that you can still see it at the higher magnification, and it shouldn't be completely out-of-focus.
Repeat for each objective, in sequence. Don't expect perfection; that is expensive and will only be found in research scopes. Try to do a scope comparison with two prepared slides. One should be a brightly-stained biological specimen and the other, something that's almost colorless.
Use different magnifications and illumination the "field stops" mentioned above. The better lenses should be obvious. Major scientific supply catalogs and some of the school supply houses will have them; this web page has a dealer contact list. However, regardless of their price, all compound microscopes utilize a set of two lenses one found in the eyepieces and one found in the objective lenses to produce a highly magnified image far beyond what our unaided eyes can see.
These sets of lenses are collectively known as a compound lens system. Compound microscopes differ from stereoscopes, another common type of microscope, in several ways.
Compound microscopes are designed to view specimens that are transparent -- they have been stained and affixed to a slide. Stereoscopes are able to view non-transparent objects at much lower magnifications than compound microscopes. The lower magnification of a stereoscope is not a shortcoming but a design decision.
Stereoscopes are used to view larger, three dimensional objects. If you wanted to view a slide of red or white blood cells, you would use a compound microscope.
However, if you wanted to look at an apple or a circuit board, you would use a stereoscope. A compound microscope needs some form of illumination. As light shines from the base of the microscope onto the object, the lens nearest the object—called the objective lens—produces an enlarged image of the object for you to view through the eyepieces.
Modern compound microscopes almost exclusively use LED illumination due to its low energy consumption and long life. When purchasing a new compound microscope, we highly suggest you purchase a microscope with LED illumination over an older halogen scope.
Image of a tumor under a compound microscope. Most microscopes also include a diaphragm that allows you to further control the amount of illumination that hits the specimen.
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