# on 03-May-2015 (Sun)

#### Flashcard 150890737

Tags
#photography
Question
The f-number N is given by:

F = f / D
where f is the focal length, and D is the diameter of the entrance pupil (effective aperture).

status measured difficulty not learned 37% [default] 0
F-number - Wikipedia, the free encyclopedia
tio in telescopes 6 Working f-number 7 History 7.1 Origins of relative aperture 7.2 Aperture numbering systems 7.3 Typographical standardization 8 See also 9 References 10 External links Notation The f-number N is given by: <span>where is the focal length, and is the diameter of the entrance pupil (effective aperture). It is customary to write f-numbers preceded by f/, which forms a mathematical expression of the entrance pupil diameter in terms of f and N.  For example, if a lens's focal length is

#### Annotation 150890754

#photography
Let f be the lens focal length, N be the lens f -number, and c be the circle of confusion for a given image format. The H hyperfocal distance is approximately given by: $$\large H\approx\frac{f^2}{Nc}$$

Depth of field - Wikipedia, the free encyclopedia
, miosis). DOF formulas The basis of these formulas is given in the section Derivation of the DOF formulae;  refer to the diagram in that section for illustration of the quantities discussed below. Hyperfocal distance <span>Let be the lens focal length, be the lens f -number, and be the circle of confusion for a given image format. The hyperfocal distance is given by Moderate-to-large distances Let be the distance at which the camera is focused (the "subject distance"). When is large in comparison with the lens focal length, the d

#### Flashcard 150890761

Tags
#photography
Question

Let f be the lens focal length, N be the lens f -number, and c be the circle of confusion for a given image format. The H hyperfocal distance is approximately given by:

$$\large H\approx\frac{f^2}{Nc}$$

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#### Original toplevel document

Depth of field - Wikipedia, the free encyclopedia
, miosis). DOF formulas The basis of these formulas is given in the section Derivation of the DOF formulae;  refer to the diagram in that section for illustration of the quantities discussed below. Hyperfocal distance <span>Let be the lens focal length, be the lens f -number, and be the circle of confusion for a given image format. The hyperfocal distance is given by Moderate-to-large distances Let be the distance at which the camera is focused (the "subject distance"). When is large in comparison with the lens focal length, the d

#### Annotation 150890767

#photography

Let s be the distance at which the camera is focused (the "subject distance"). When s is large in comparison with the lens focal length, the distance DN from the camera to the near limit of DOF and the distance DF from the camera to the far limit of DOF are (approximately):

$$\large D_N\approx\frac{Hs}{H+s}$$

and

$$D_F\approx\frac{Hs}{H-s}$$ for s<H

The depth of field DF - DN is

$$\large DOF\approx\frac{2Hs^2}{H^2-s^2}$$

Depth of field - Wikipedia, the free encyclopedia
ities discussed below. Hyperfocal distance Let be the lens focal length, be the lens f -number, and be the circle of confusion for a given image format. The hyperfocal distance is given by Moderate-to-large distances <span>Let be the distance at which the camera is focused (the "subject distance"). When is large in comparison with the lens focal length, the distance from the camera to the near limit of DOF and the distance from the camera to the far limit of DOF are and The depth of field is Substituting for and rearranging, DOF can be expressed as Thus, for a given image format, depth of field is determined by three factors: the focal length of the lens, the f -number

#### Flashcard 150890777

Tags
#photography
Question

Let s be the distance at which the camera is focused (the "subject distance"). When s is large in comparison with the lens focal length, the distance DN from the camera to the near limit of DOF and the distance DF from the camera to the far limit of DOF are (approximately):

DN [...]

and

$$D_F\approx\frac{Hs}{H-s}$$ for s<H

The depth of field DF - DN is

$$\large DOF\approx\frac{2Hs^2}{H^2-s^2}$$

$$\large D_N\approx\frac{Hs}{H+s}$$

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#### Original toplevel document

Depth of field - Wikipedia, the free encyclopedia
ities discussed below. Hyperfocal distance Let be the lens focal length, be the lens f -number, and be the circle of confusion for a given image format. The hyperfocal distance is given by Moderate-to-large distances <span>Let be the distance at which the camera is focused (the "subject distance"). When is large in comparison with the lens focal length, the distance from the camera to the near limit of DOF and the distance from the camera to the far limit of DOF are and The depth of field is Substituting for and rearranging, DOF can be expressed as Thus, for a given image format, depth of field is determined by three factors: the focal length of the lens, the f -number

#### Flashcard 150890792

Tags
#photography
Question

Let s be the distance at which the camera is focused (the "subject distance"). When s is large in comparison with the lens focal length, the distance DN from the camera to the near limit of DOF and the distance DF from the camera to the far limit of DOF are (approximately):

$$\large D_N\approx\frac{Hs}{H+s}$$

and

DF [...]

The depth of field DF - DN is

$$\large DOF\approx\frac{2Hs^2}{H^2-s^2}$$

$$D_F\approx\frac{Hs}{H-s}$$ for s<H

status measured difficulty not learned 37% [default] 0

Open it

#### Original toplevel document

Depth of field - Wikipedia, the free encyclopedia
ities discussed below. Hyperfocal distance Let be the lens focal length, be the lens f -number, and be the circle of confusion for a given image format. The hyperfocal distance is given by Moderate-to-large distances <span>Let be the distance at which the camera is focused (the "subject distance"). When is large in comparison with the lens focal length, the distance from the camera to the near limit of DOF and the distance from the camera to the far limit of DOF are and The depth of field is Substituting for and rearranging, DOF can be expressed as Thus, for a given image format, depth of field is determined by three factors: the focal length of the lens, the f -number

#### Flashcard 150890804

Tags
#photography
Question

Let s be the distance at which the camera is focused (the "subject distance"). When s is large in comparison with the lens focal length, the distance DN from the camera to the near limit of DOF and the distance DF from the camera to the far limit of DOF are (approximately):

$$\large D_N\approx\frac{Hs}{H+s}$$

and

$$D_F\approx\frac{Hs}{H-s}$$ for s<H

The depth of field DF - DN is

DOF [...]

$$\large DOF\approx\frac{2Hs^2}{H^2-s^2}$$

status measured difficulty not learned 37% [default] 0

Open it

#### Original toplevel document

Depth of field - Wikipedia, the free encyclopedia
ities discussed below. Hyperfocal distance Let be the lens focal length, be the lens f -number, and be the circle of confusion for a given image format. The hyperfocal distance is given by Moderate-to-large distances <span>Let be the distance at which the camera is focused (the "subject distance"). When is large in comparison with the lens focal length, the distance from the camera to the near limit of DOF and the distance from the camera to the far limit of DOF are and The depth of field is Substituting for and rearranging, DOF can be expressed as Thus, for a given image format, depth of field is determined by three factors: the focal length of the lens, the f -number

#### Annotation 150890813

#photography
The hyperfocal distance is the nearest focus distance at which the DOF extends to infinity

Depth of field - Wikipedia, the free encyclopedia
us and f -number from DOF limits. Some view cameras include DOF calculators that indicate focus and f -number without the need for any calculations by the photographer (Tillmanns 1997, 67–68; Ray 2002, 230–31). Hyperfocal distance <span>The hyperfocal distance is the nearest focus distance at which the DOF extends to infinity; focusing the camera at the hyperfocal distance results in the largest possible depth of field for a given f -number (Ray 2000, 55). Focusing beyond the hyperfocal distance does not in

#### Flashcard 150890817

Tags
#photography
Question
The hyperfocal distance is the [...] at which the DOF extends to infinity
nearest focus distance

status measured difficulty not learned 37% [default] 0

#### Parent (intermediate) annotation

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The hyperfocal distance is the nearest focus distance at which the DOF extends to infinity

#### Original toplevel document

Depth of field - Wikipedia, the free encyclopedia
us and f -number from DOF limits. Some view cameras include DOF calculators that indicate focus and f -number without the need for any calculations by the photographer (Tillmanns 1997, 67–68; Ray 2002, 230–31). Hyperfocal distance <span>The hyperfocal distance is the nearest focus distance at which the DOF extends to infinity; focusing the camera at the hyperfocal distance results in the largest possible depth of field for a given f -number (Ray 2000, 55). Focusing beyond the hyperfocal distance does not in

#### Flashcard 150890823

Tags
#photography
Question
The hyperfocal distance is the nearest focus distance at which the [...]
DOF extends to infinity

status measured difficulty not learned 37% [default] 0

#### Parent (intermediate) annotation

Open it
The hyperfocal distance is the nearest focus distance at which the DOF extends to infinity

#### Original toplevel document

Depth of field - Wikipedia, the free encyclopedia
us and f -number from DOF limits. Some view cameras include DOF calculators that indicate focus and f -number without the need for any calculations by the photographer (Tillmanns 1997, 67–68; Ray 2002, 230–31). Hyperfocal distance <span>The hyperfocal distance is the nearest focus distance at which the DOF extends to infinity; focusing the camera at the hyperfocal distance results in the largest possible depth of field for a given f -number (Ray 2000, 55). Focusing beyond the hyperfocal distance does not in