The angle that the lens sees
Angle of View
Opening in the lens that regulates the amount of light (iris)
Stopping down the aperture ... the amount of light (brightness) and ... the sharpness (depth of field).
Distance between focal point and the lens plane
Lenses with shorter focal length are called
The distance between the object and front of the lens
What does too short of a working distance have some influence on?
- Hygiene Problem
- Patient Discomfort
- Image Distortion
How does a working distance that is too far affect the image?
- More items will appear in the frame
- Distrub the point of focus
The distance from the nearest to the furthest point of sharp focus
Depth of field
What does the depth of field depend on?
What are 3 advantages to a Ring Flash?
- Light surrounds the optical axis
- In accessible objects in oral cavities will all be lit evenly
- Natural color rendition
What are 2 disadvantages to Ring Flashes?
- Produces images without shadows (which are needed to create a 3D effect)
- Images tend to look flat
What does the high intensity of light from a twin flash system result in?
narrowing down the lens opening and therefor increases the depth of field
When taking a photograph of bright surfaces, images will tend to be...
darker or underexposed image
When taking a photograph of dark surfaces, images will tend to be...
too light or over exposed image
What corrections on the camera settings are needed to compensate for the flash exposure of dark objects?
- Reduce aperture
- Preset the exposure compensation in the camera to the negative value
What corrections on the camera settings are needed to compensate for the flash exposure of bright objects?
- Manually increase aperture
- Adjust the exposure set up in the camera to a positive value
If light comes parallel to the optical axis (ring flash), what will be the effect on illumination?
very flat (not recommended for Portrait and Object Photography)
What is the advantage of Aperture Priority (A) Mode?
Controlling the depth of field by pre setting the aperture
What does Manual Mode (M) preset on the camera?
Aperture and Exposure time (shutter speed)
What view is recommended for orthodontic, periodontal and prosthetic documentaion?
What are the Standard Views?
- Frontal View (both arches)
- Lateral View
- Occlusal Mandibular View
- Occlusal Maxillary View
What is the frontal view of the arch useful for?
Prosthetic and Periodontal Purpose
What is the lateral view of the front teeth mainly used for?
Anterior teeth together to verify the bite for prosthetic and orthodontic purposes
When using a mirror to take a lateral view of posterior teeth, the optical access should be?
Perpendicular to the mirror image