Chapter 1 - Imaging Flashcards
Define resolution
the size of the smallest feature that can be distinguished in an image.
Bytes per pixel for full colour?
3 bytes
Adding colour mixing (light)
Red,Green, and Blue mix to make ; R+G=Yellow R+B=Magenta G+B=Cyan R+G+B=white
subtractive colour mixing (filters and pigments)
Magenta,Yellow, and Cyan mix to make ; M+Y=Red M+C=Blue Y+C=Green M+Y+C=Black (K)
EM spectrum in increasing frequency and decreasing wavelength.
Radiowave Micromave Infrared Visible Light Ultravilot Xray GammaRay
λ and f of red light
7x10^-7m 4x10^14Hz
λ and f of green light
5x10^-7m 6x10^14Hz
λ and f of blue light
4x10^-7m 7x10^14Hz
define noise
Random changes to a pixel colour value that makes it clearly out of place
define noise
Random changes to a pixel colour value that makes it clearly out of place
Three types of converging lens
Biconvex, Plano-convex, concave-convex(converging minuscules)
Three types of diverging lens
Biconvex, Plano-concave, convex-concave(diverging minuscules)
Curvature of a wavefront =
1/radius in dioptre D
Lens makers equation.
1/v = 1/u + 1/f (v=image distance, u=object distance, f=curvature added by lens. note make sure the distances are from the lens and +- depending on direction)
power of a lens
1/f
What happens to an image if the object is beyond 2F’?
Image is
- between F and 2F
- smaller (diminished)
- real image
- inverted
What happens to an image if the object is at 2F’?
Image is
- at 2F
- same size
- real image
- inverted
What happens to an image if the object is between F’ and 2F’?
Image is
- beyond 2F
- magnified
- real image
- inverted
What happens to an image if the object is between F’ and lens?
Image is
- further back then object
- magnified
- virtual image
- erect
Image magnification equation
I/0 = v/u
magnification =(I/O or v/u)
normal sight near point and far point?
near point:25cm
Far point: infinite
What causes short sight and what lens corrects it?
Too much converging power, so NP and FP are too close , focused infort of the retina.
fixed with a diverging lens (negative power)
What causes long sight and what lens corrects it?
Too little converging power, so NP and FP are too far away , focused behind of the retina.
fixed with a converging lens (positive power)
How do you measure distane from camera to an object to use in a ratio between two distances question.
Distance camera-object= 1/objectsize
(make sure to measre both objects in the same direction.)
