WEEK 2 Flashcards
what is focal length?
what is a lens’s feild of view
“refers to placing people behind rather than blocking them”
z axis
________ lenses reveal more of what is infront of the camera
wide angle
_________ reveal less of what is infront of the camera
telephoto
“when light bends inward to a single point”
refractions
wider lenses ___________________
seperate background and foreground
narrow lenses __________
compress
3 points of the exposure triangle!
aperture, shutter speed, iso
_________is the amount of light coming through a lens, measured as f-stops
aperture/iris
Each time we half or double light it’s called a _______
a stop! (f/1.4, f/2, f/5.6, f/8, f/16, f/24)
*the smaller the number the wider the lens
when you close the iris you are letting ________ light in
LESS
what are transmission stops?
T-stops are a measurement of how much light is actually going through the lens at any given f-stop
measured in degrees or fractions, amount of light coming through a lens per frame
shutter!
Creates motion blur
Slow shutter = 1/15 (makes it blurry)
Medium shutter = 1/60 (less blurry)
Fast shutter = 1/2000 (still picture)
shutter info
based on distance, measured out on focal plane (from camera to subject)
focus!
*Measure distance to talent’s eye
Adjust lens to correct distance
Mark position on follow focus rings
distance between nearest and farthest objects in focus
depth of feild (DOF)!
*Aperture and focal length affect DOF
Wider lenses have larger DOF, longer lenses have shallower DOF
Shallower DOF means aperture is too big (f/4), too deep DOF means aperture is too small (f/22)
wider lenes have ________ depth of feild
larger
longer lenses have ______ depth of feild
shallower
Why do we zoom to focus?
By zooming to focus, we achieve shallowest DOF, allowing operator to be critical when determining focus
Shallower DOF means aperture is too __________(f/4),
big
too deep DOF means aperture is too ________(f/22)
small
TYPES OF LENSES
-Have focus and iris only
-Having fewer glass elements means having a sharper image
Prime lenses: fixed focal length
TYPES OF LENSES
- Use combination of 1 concave and 2 convex lenses (on equal plane) to manipulate field of view
- Moving concave lens shifts field of view from wide to narrow
-Sometimes a fourth “focusing lens” is used to adjust final refraction to achieve focus
Zoom lenses: variable focal length
- canon photography zoom lens
- focus changes as you change focal length
varifocal
- canon video zoom lens
- focus stays consistent as you change focal length
parifocal
- variable focal length
- wide range from wide photo
- may include OIS
- manual and servo
- may include a telephoto
extender
-fast
zoom lens advantages
-heavy
- can lose backfocus
- softer image
- more expensive
zoom lens disadvantages
