This PPT prepared using mainly the Elements of Photogrammetry book as references with some online resources.

1. © 2018 Dr. Sarhat M Adam
BSc in civil Engineering
Msc in Geodetic Surveying
PhD in Engineering Surveying & Space Geodesy
Note – Figures and materials in the slides may be the authors own work or
extracted from internet websites, Materials by Duhok or Nottingham
universities staff and their slides, author's own knowledge, or various internet
image sources and books.
Lecture 03
Fundamental Optics

2. Fundamentals Optics
Outlines
 Thick Lenses
 Lenses Distortion
 Lens Resolution
 Lens DoF
 Illuminance
 Shutter & Aperture

3. Fundamentals Optics
Thick Lenses
 Former assumption on lenses considered thickness negligible.
 With thick lenses, this assumption is no longer valid.
 Nodal points must be defined for thick lenses.
 Called incident nodal point and the emergent nodal point.

4. Fundamentals Optics
Thick Lenses
 (f) of thick lens is the distance from N′ to this plane of infinite
focus.
 It is impossible for a single lens to produce a perfect image.
 Always be somewhat blurred and geometrically distorted.
 The imperfections called aberrations.
 Using of additional lens elements able to correct for aberrations.
 Lens distortions do not degrade image quality but deteriorate the
geometric quality (or positional accuracy) of the image.
 They are ether symmetric radial, or decentering.
 Both occur if light rays are bent, or change directions.

5. Fundamentals Optics
Distortion
 A) Symmetric Radial
 B) decentering distortion
 Matlab

6. Fundamentals Optics
Lens resolution
 Resolution is important in
photogrammetry
 Resolution or resolving of lens
 Measures by two methods
 Lines/mm and MTF

7. Fundamentals Optics
Lens DoF
 Object distance that can be accommodated by a lens
 Without deterioration
 Aperture dependent.
 The shorter the focal
 The shorter the f, the greater its depth of field.

8. Fundamentals Optics
Illuminance

9. Fundamentals Optics
Shutter & Aperture
 illuminance and time of exposure unit is meter candle-seconds
 f-stop settings variation made by aperture which controlled by
Diaphragm.
 As the diameter of the aperture increases, enabling faster
exposures, DoF become less & lens distortion become more.
 To maximize DoF, slow shutter speed and large f-stop setting.
 To photograph rapid moving objects, a fast shutter speed is
essential.
 If aperture area is doubled, total exposure is doubled.
 If shutter time is halved and aperture area is doubled, total
exposure remains unchanged.

10. Fundamentals Optics
Shutter & Aperture
 Nominal f-stop (1, 1.4, 2.0, 2.8, 4.0, 5.6, 8.0, 11, 16, 22, and 32).
 The aperture diameter equals the lens focal length. (f/d)=1.0.
 f-1.4 halves the aperture area from that of f-1.
 Nominal f-stops listed previously halves the aperture area of the
preceding one.
 Digital Camera in addition to manual, has
1. Fully automatic mode, where both f-stop and shutter speed are
appropriately selected.
2. Aperture priority mode, where the user inputs a fixed f-stop
and the camera selects the appropriate shutter speed, and
3. Shutter priority mode, where the user inputs a fixed shutter
speed and the camera selects the appropriate f-stop.

11. Fundamentals Optics
Shutter & Aperture

12. Fundamentals Optics
Example
 Suppose that a photograph is optimally exposed with an f-
stop setting of f-4 and a shutter speed of 1/500 s. What is
the correct f-stop setting if shutter speed is changed to
1/1000s?
Solution
Total exposure is the product of diaphragm area and shutter
speed. This product must remain the same for the 1/1000 -s
shutter speed as it was for the 1/500-s shutter speed, or
A1time1=A2time2
 Let d1 and d2 be diaphragm diameters for 1/500- and
1/1000 -s shutter times, respectively.

13. Fundamentals Optics
Example
 Then the respective diaphragm areas are