Difference between revisions of "TTL"
(making this much simpler) |
m (where) |
||
| Line 9: | Line 9: | ||
|image_rights= fair use | |image_rights= fair use | ||
}} | }} | ||
| − | Through The Lens: referring to in-camera [[camera#TTL Metering|exposure metering]] with photocells somewhere in the light path of the taking lens; making a distinction from older designs where a [[CdS]] or [[Selenium meter | selenium]] meter cell was attached | + | Through The Lens: referring to in-camera [[camera#TTL Metering|exposure metering]] with photocells somewhere in the light path of the taking lens; making a distinction from older designs where a [[CdS]] or [[Selenium meter | selenium]] meter cell was attached somewhere atop the camera body, but could not take into account light loss from filters, lens extension, etc, |
TTL flash exposure control is another common meaning. But depending on context the term might also differentiate [[viewfinder]] designs, [[autofocus]] mechanism designs, or other camera systems. | TTL flash exposure control is another common meaning. But depending on context the term might also differentiate [[viewfinder]] designs, [[autofocus]] mechanism designs, or other camera systems. | ||
Revision as of 00:08, 7 June 2021
- The acronym TTL most commonly refers to,
|
| A diagram from Ricoh indicates two approaches to TTL exposure metering (Image rights) |
Through The Lens: referring to in-camera exposure metering with photocells somewhere in the light path of the taking lens; making a distinction from older designs where a CdS or selenium meter cell was attached somewhere atop the camera body, but could not take into account light loss from filters, lens extension, etc,
TTL flash exposure control is another common meaning. But depending on context the term might also differentiate viewfinder designs, autofocus mechanism designs, or other camera systems.
- But,
Transistor-Transistor Logic: TTL is a type of digital electronic circuitry which uses transistors and resistor elements (usually made of transistors) to make logic gates. It is rarely, if ever used in camera circuitry as it has fairly high power consumption.
