Lesson 11 : 24.5.2010
Lens Aberration Assignment Pressentation
Todays lesson was used to give our speeches on our lens aberration assignment Elanna and Sophie were my group members and we did a short powerpoint pressentation and speech demonstrating the task and the results that we obtained.
Sunday, August 1, 2010
Lesson 10 : 17.5.2010 - Image Performance, Display and Storage
Lesson 10 : 17.5.2010
Image Performance, Display and Storage
This lesson i found to be very useful with the upcoming submissions of this semesters work. We watched a demonstration on how to display and mount our photographs.
Mounting Equipment
- Metal Ruler
- Stanley Knife (Blade must not bend)
- Matte Cutter
- Use either white or off-white no colour!
- Foamcore or window mount
- Acid free and ligment free
Cardboard Material Brands
- Novocore = Low Quality
- Alfamatte = Medium Quality
- Alfarag/Ragboard = High Quality
Image Performance, Display and Storage
This lesson i found to be very useful with the upcoming submissions of this semesters work. We watched a demonstration on how to display and mount our photographs.
Mounting Equipment
- Metal Ruler
- Stanley Knife (Blade must not bend)
- Matte Cutter
- Use either white or off-white no colour!
- Foamcore or window mount
- Acid free and ligment free
Cardboard Material Brands
- Novocore = Low Quality
- Alfamatte = Medium Quality
- Alfarag/Ragboard = High Quality
Lesson 9 : 10.5.2010 - Copyright Law and the Photographer
Lesson 9 : 10.5.2010
Copyright Law and the Photographer
Powerpoint pressentation and talk on the copright laws that effect photographers.
Website: Australian Copy Right Council
Learnt a lot of information that i believe will become more relevant as we move into the workforce as a photographer. The most interesting thing that I found was that the Copyright length of protection is the life of the creator plus 70 years.
Copyright Law and the Photographer
Powerpoint pressentation and talk on the copright laws that effect photographers.
Website: Australian Copy Right Council
Learnt a lot of information that i believe will become more relevant as we move into the workforce as a photographer. The most interesting thing that I found was that the Copyright length of protection is the life of the creator plus 70 years.
Lesson 8 : 3.5.2010 - Maximum Lens Aperture
Lesson 8 : 3.5.2010 - Maximum Lens Aperture
Maximum Lens Aperture
- How large the hole opens
- Figure is shown on the lens
- Ratio 1:1.4 = Max Aperture Diameter : Lens Focal Length
eg. If lens focal length = 50mm the max aperture would be 1:4 and the aperture diameter would be 35.7
- For every 1mm of aperture diameter there is 1:4mm of focal length.
Relative Lens Apertrue - Each f number is related to the lens focal length
f2 on a 25mm lens has aperture diameter of 12.5mm
f2 on a 50mm lens has aperture diameter of 25mm
f2 on a 100mm lens has aperture diameter of 50mm
Lens Aberations is an optical error
- no lens is perfect
- many aberrations can be corrected by inducing
- alternative errors in the lens
- some errors are welcomed - soft focus lens
Why do aberrations exist?
- light is bent or refracted as it passes through glass
- amount of refraction varies with wavelength of light
- different wavelengths do not focus at same point
Chromatic Aberration (Colour)
- light passing through glass is dispersed into its colours
- axial (logitudinal) and transverse (lateral)
- common in long and wide lenses
- addition of flourite in glass reduces this
Coma
- an off-axis spherical aberration creating cone shaped points
- stopping down can slightly reduce effect
- can be reduced through deliberate use of other aberrations
Astigmatism
- off-axis aberration causing vertical and horizontal lines to to be focused in two different planes
- reduced slightly by stopping down
Maximum Lens Aperture
- How large the hole opens
- Figure is shown on the lens
- Ratio 1:1.4 = Max Aperture Diameter : Lens Focal Length
eg. If lens focal length = 50mm the max aperture would be 1:4 and the aperture diameter would be 35.7
- For every 1mm of aperture diameter there is 1:4mm of focal length.
Relative Lens Apertrue - Each f number is related to the lens focal length
f2 on a 25mm lens has aperture diameter of 12.5mm
f2 on a 50mm lens has aperture diameter of 25mm
f2 on a 100mm lens has aperture diameter of 50mm
Lens Aberations is an optical error
- no lens is perfect
- many aberrations can be corrected by inducing
- alternative errors in the lens
- some errors are welcomed - soft focus lens
Why do aberrations exist?
- light is bent or refracted as it passes through glass
- amount of refraction varies with wavelength of light
- different wavelengths do not focus at same point
Chromatic Aberration (Colour)
- light passing through glass is dispersed into its colours
- axial (logitudinal) and transverse (lateral)
- common in long and wide lenses
- addition of flourite in glass reduces this
Coma
- an off-axis spherical aberration creating cone shaped points
- stopping down can slightly reduce effect
- can be reduced through deliberate use of other aberrations
Astigmatism
- off-axis aberration causing vertical and horizontal lines to to be focused in two different planes
- reduced slightly by stopping down
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