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Does the numerical aperture of an objective depend on the focal length of the objective?
Wiki User
∙ 9y ago
Yes.
Wiki User
∙ 9y ago
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What is the meaning of f3.5-5.6?
On for instance a 35-70mm camera lens the maxmimum aperture at 35mm is f3.5 and the maximum aperture at 70mm is f5.6. (f3.5-5.6) Maximum Aperture of a Variable Focal Length Camera Lens.
How is magnifying power of telescope and a microscope are a affected by increasing the focal length of their objectives?
The magnification of a telescope M is the the focal length of the objective Fo over the focal length of the eyepiece Fe so increasing the focal length of the objective increases the magnification. The magnification of a microscope M is approximately tube length L/Fo x 25/Fe. Therefore increasing the focal length of the objective reduces the magnification.
What are the optical parts of the microscope. How does it achieve magnification and Resolution?
The main parts of an optical microscope are: the eyepiece, objective lense and light source (sometimes a mirror). The objective lense has a short focal length so it produces an image a little bit up the microscope's tube which is then magnified by the eyepiece. Resolution is dependant on the numerical appeture of the lense and the wavelenght of the light source used.
What is more powerful out of the Objective or the Eye piece lens?
The focal length of EyePiece is relatively larger to that of the Objective lens. Power of a lens is inversely proportional to it's focal length. Therefore, Objective is slightly more powerful than EyePiece.
Why is the focal length of the objective lens in a microscope short?
To improve magnification. Also so that we can get a real and inverted image
Why is oil necessary when using the 90x to 100x objective?
The oil immersion fills the space between the objective and the specimen and matches the refractive index of the glass coverslip and glass objective lens. At a given focal length, this allows you to acheive a greater numerical aperature (better light collection efficiency, better resolution).
Four assessments of the quality of the image being seen using a light microscope?
[1] Brightness - How light or dark is the image? Brightness is related to the illumination system and can be changed by changing the voltage to the lamp (rheostat) and adjusting the condenser and diaphragm/pinhole apertures. Brightness is also related to the numerical aperture of the objective lens (the larger the numerical aperture, the brighter the image).[2] Focus - Is the image blurry or well-defined? Focus is related to focal length and can be controlled with the focus knobs. The thickness of the cover glass on the specimen slide can also affect your ability to focus the image -- it can be too thick for the objective lens. The correct cover-glass thickness is written on the side of the objective lens.[3] Resolution - How close can two points in the image be before they are no longer seen as two separate points? Resolution is related to the numerical aperture of the objective lens (the higher the numerical aperture, the better the resolution) and the wavelength of light passing through the lens (the shorter the wavelength, the better the resolution).[4] Contrast - What is the difference in lighting between adjacent areas of the specimen? Contrast is related to the illumination system and can be adjusted by changing the intensity of the light and the diaphragm/pinhole aperture. Also, chemical stains applied to the specimen can enhance contrast.
List the four assessments of the quality of the image being seen using a light microscope?
[1] Brightness - How light or dark is the image? Brightness is related to the illumination system and can be changed by changing the voltage to the lamp (rheostat) and adjusting the condenser and diaphragm/pinhole apertures. Brightness is also related to the numerical aperture of the objective lens (the larger the numerical aperture, the brighter the image).[2] Focus - Is the image blurry or well-defined? Focus is related to focal length and can be controlled with the focus knobs. The thickness of the cover glass on the specimen slide can also affect your ability to focus the image -- it can be too thick for the objective lens. The correct cover-glass thickness is written on the side of the objective lens.[3] Resolution - How close can two points in the image be before they are no longer seen as two separate points? Resolution is related to the numerical aperture of the objective lens (the higher the numerical aperture, the better the resolution) and the wavelength of light passing through the lens (the shorter the wavelength, the better the resolution).[4] Contrast - What is the difference in lighting between adjacent areas of the specimen? Contrast is related to the illumination system and can be adjusted by changing the intensity of the light and the diaphragm/pinhole aperture. Also, chemical stains applied to the specimen can enhance contrast.FROM VLA hacker
What is the formula for light gathering power for telescopes?
For visual observation: Magnification = (Focal Length of Objective Lens) divided by (Focal Length of Eyepiece) (They have to be measured in the same units.) For prime-focus photography: (One focal-length of the Objective Lens on the film) = (one radian in the sky)
What is the limited resolution formula?
D = wavelength / NA condensor + NA objective D being minimum distance at which two points can be resolved....... wave length of light used......condensor and objective are the numerical apertures of the condensor lens and objective lens
Would the ocular unit increase or decrease as magnification increases?
Field of view will decrease as the aperture remain same but things become larger and so we can see smaller area after magnification
Do the aperture controls adjust the length of time the light strikes the sensor?
No, the aperture controls adjust the size of the opening that light enters the camera through (see image above, left maximum aperture setting, right minimum aperture setting).
What is the importance of oil in oil immersion lens of compound microscope?
In light microscopy, oil immersion is a technique used to increase the resolution of a microscope. This is achieved by immersing both the objective lens and the specimen in a transparent oil of high refractive index, thereby increasing the numerical aperture of the objective lens.
What is the meaning of f3.5-5.6?
On for instance a 35-70mm camera lens the maxmimum aperture at 35mm is f3.5 and the maximum aperture at 70mm is f5.6. (f3.5-5.6) Maximum Aperture of a Variable Focal Length Camera Lens.
The depth of field in a photograph is controlled by the?
Depth of field on a camera is controlled by the aperture. The aperture is basically the size of the opening in the lens. A large aperture (or opening) creates a shallower depth of field and a small aperture creates a greater depth of field. Aperture, along with shutter speed, determine how much light goes into the camera. The size of the aperture is indicated by the f/stop number. The numbers usually range from about f/1 to around f/64. The smaller the number is, the larger the aperture is and the shallower the depth of field, meaning less space is in focus.Additional AnswerDepth of field is also affected by the focal length of your camera's lens. For any given aperture, longer focal length lenses (telephoto lenses) have a much narrower depth of field than a standard lens, and shorter focal length lenses (wide-angle lenses) have a much wider depth of field than a standard lens.
How are the numbers related to the length of the objective?
Because the length of the objectives depends on the total magnification. Example: Magnification: 50x (LPO) You can see that the lower the magnification,the length of objective is the smallest. Magnification: 500x (HPO) You can see that the higher the magnification, the length of objective is bigger than the other objectives. If the objective is lower, the number is lesser -Guinean026
What happens if you decrease a telescopes eyepiece focal length?
The magnification of the telescope image is(focal length of the objective) divided by (focal length of the eyepiece).The focal length of the objective is fixed.Decreasing the focal length of the eyepiece increases the magnification of the image.(But it also makes the image dimmer.)
