The Human Eye and the Camera
SONNY P. DE LEON
Master Teacher I
Components of the lesson
• Parts and function of the Human Eye vital in
seeing objects
• Parts and function of the Camera in forming
images
Seatwork No.2
The Human Eye and the Camera
1. What are the parts of the eye vital in seeing objects?
2. Describe the mechanism of how the human eyes see an object.
3. How will you describe the image formed in the eye?
4. What is accommodation?
5 .Identify the parts of the camera responsible in the production of
image?
6. Explain how the image is formed in the camera.
7. Describe the image formed in the camera?
8. Draw the ray diagram for the image formation in the eye and the
camera.
9. What are similarities of the parts of the camera
and human eye?
10. What are the specific differences bet. camera
and eye?
Do you see a similarity between a camera and the human eye?
Eye vs. Camera
ANATOMY OF HUMAN EYE
Image Formation in the Eye
Image formed
diminished.
is
real,
inverted
and
• The eye uses a convex lens system to form a small upside
down image of anything in front of it.
• The iris controls the amount of light going into the eye. If
you walk into a dark room, the hole in the middle of the iris
(the pupil) grows larger.
• The cornea and the watery liquid behind it do most of the
focusing of the rays.
• The lens itself makes small focusing adjustments. It
doesn’t move backwards or forwards like the lens in a
camera or projector. Instead it becomes thinner or fatter.
• The retina is the ‘screen’ which detects the image. It
contains millions of tiny cells which are sensitive to light.
The cells send signals along the optic nerve to the brain.
• Your brain gives you an upright view of the world. But it
isn’t always the same as the image in your eye.
• The eye uses a convex lens system to produce a real
inverted image of an object in front of it. Light entering the
eye passes first into the cornea. It is where where most
refraction occurs. A resulting image is focused on the retina
as an inverted image. The brain receives the message
through the optic nerve and interprets the image as an
upright object.
• Clear images of near and far objects are not visible
together. To view closer objects after viewing distant
objects requires a change in the curvature of the lens of the
eye.
-For viewing distant objects the lens is thinner and is
focal length is longer.
- For closer objects the lens thickens in the middle and
its principal focus is closer to the lens.
ACCOMMODATION
The ability of the eye to change its focal length.
1.2 Describe the mechanism of how the human
eyes see an object.
CORNEA
AQUEOUS HUMOR
PUPIL
IRIS
RETINA
BRAIN
LENS
The CAMERA
Image formation in the Camera
• The image formed is real, inverted, and
reduced.
• Lens - It draws the light into the camera and focuses it on the
film plane.
• Aperture- opening in the camera through which light enters.
• Shutter - It open and closes to control the length of time light
strikes the film.
• Shutter Release - The button that releases or "trips" the shutter
mechanism.
• Iris diaphragm- It changes the size of the lens opening/ regulate
the light that enters the camera
• Viewfinder - The "window" through which you look to frame
your picture.
• Film – place behind the iris diaphragm where the image is
formed.
• Film Rewind Knob -This knob rewinds the film back
into the film cassette.
• Camera Body - The casing of the camera which holds
the encloses the camera pats.
• Flash Shoe - This is the point at which the flash or
flash cube is mounted or attached.
• Self-Timer - This mechanism trips the shutter after a
short delay - usually 7 to 10 seconds - allowing
everyone to be in the photograph.
• Shutter Speed Control - This know controls the length
of time the shutter remains open.
B
RECALL!
1.1. What are the parts of the eye vital in
seeing objects?
• The eye uses a convex lens system to form a small upside
down image of anything in front of it.
• The iris controls the amount of light going into the eye. If
you walk into a dark room, the hole in the middle of the iris
(the pupil) grows larger.
• The cornea and the watery liquid behind it do most of the
focusing of the rays.
• The lens itself makes small focusing adjustments. It
doesn’t move backwards or forwards like the lens in a
camera or projector. Instead it becomes thinner or fatter.
• The retina is the ‘screen’ which detects the image. It
contains millions of tiny cells which are sensitive to
light. The cells send signals along the optic nerve to
the brain.
• Your brain gives you an upright view of the world.
But it isn’t always the same as the image in your
eye.
1.3 How will you describe the image
formed in the eye?
• It is always real, inverted, and
magnification < 1.
1.3 Identify the parts of the camera responsible in
the production of image?
• Lens - It draws the light into the camera and focuses it
on the film plane.
• Aperture- opening in the camera through which light
enters.
• Shutter - It open and closes to control the length of time
light strikes the film.
• Iris diaphragm- It changes the size of the lens opening/
regulate the light that enters the camera
• Film – place behind the iris diaphragm where the image
is formed.
1.4 Explain how the image is formed
in the camera.
APERTURE
Iris diaphragm
LENS
FILM
Comparison Between the Eye and the
Camera
VS.
Eye vs. Camera
Similarities of the parts of the
camera and human eye
Eye
Camera
Retina
Film
Lens
Lens
Iris
Iris diaphragm
Pupil
Aperture
Eyelid
Shutter
B
Specific Differences bet. Camera
and eye
Camera
Eye
Lens
Rigid
Deformable
Focusing
By moving lens relative to
film
By changing shape
Aperture
Controlled by diaphragm
Controlled by Iris
Exposure
Controlled by shutter
Continuous
Light-sensitive Surface
Photographic film
Retina
Ray Diagram of
Camera and Eye
Image formation in the Camera
• The image formed is real, inverted, and
reduced.
Image Formation in the Eye
BACK..
Compound Microscope
Use a lens combination to make small objects near the
objective seem more visible.
objective lens: real,inverted, and magnified
eyepiece lens: virtual, erect and further magnified
Refracting Telescope
Use a lens combination to make distant objects more
visible
That’s All..
THANK YOU VERY MUCH!!