enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Magnification - Wikipedia

    en.wikipedia.org/wiki/Magnification

    Optical magnification is the ratio between the apparent size of an object (or its size in an image) and its true size, and thus it is a dimensionless number. Optical magnification is sometimes referred to as "power" (for example "10× power"), although this can lead to confusion with optical power.

  3. f-number - Wikipedia

    en.wikipedia.org/wiki/F-number

    where N is the uncorrected f-number, NA i is the image-space numerical aperture of the lens, | | is the absolute value of the lens's magnification for an object a particular distance away, and P is the pupil magnification. Since the pupil magnification is seldom known it is often assumed to be 1, which is the correct value for all symmetric lenses.

  4. Numerical aperture - Wikipedia

    en.wikipedia.org/wiki/Numerical_aperture

    [3] [5] The magnification here is typically negative, and the pupil magnification is most often assumed to be 1 — as Allen R. Greenleaf explains, "Illuminance varies inversely as the square of the distance between the exit pupil of the lens and the position of the plate or film. Because the position of the exit pupil usually is unknown to the ...

  5. Optical telescope - Wikipedia

    en.wikipedia.org/wiki/Optical_telescope

    To find what eyepiece is required to get minimum magnification one can rearrange the magnification formula, where it is now the division of the telescope's focal length over the minimum magnification: =. An eyepiece of 35 mm is a non-standard size and would not be purchasable; in this scenario to achieve 100% one would require a standard ...

  6. Lens - Wikipedia

    en.wikipedia.org/wiki/Lens

    This magnification formula provides two easy ways to distinguish converging (f > 0) and diverging (f < 0) lenses: For an object very close to the lens (0 < S 1 < | f |), a converging lens would form a magnified (bigger) virtual image, whereas a diverging lens would form a demagnified (smaller) image; For an object very far from the lens (S 1 ...

  7. List of optics equations - Wikipedia

    en.wikipedia.org/wiki/List_of_optics_equations

    Visulization of flux through differential area and solid angle. As always ^ is the unit normal to the incident surface A, = ^, and ^ is a unit vector in the direction of incident flux on the area element, θ is the angle between them.

  8. Angle of view (photography) - Wikipedia

    en.wikipedia.org/wiki/Angle_of_view_(photography)

    In this case, the magnification factor (m) must be taken into account: = (+) (In photography m {\displaystyle m} is usually defined to be positive, despite the inverted image.) For example, with a magnification ratio of 1:2, we find f = 1.5 ⋅ F {\displaystyle f=1.5\cdot F} and thus the angle of view is reduced by 33% compared to focusing on a ...

  9. Apparent magnitude - Wikipedia

    en.wikipedia.org/wiki/Apparent_magnitude

    Limiting Magnitudes for Visual Observation at High Magnification [14] Telescope aperture (mm) Limiting Magnitude 35 11.3 60 12.3 102 ... Inverting the above formula, ...