If youâve spent any time online searching for a used car, youâve probably seen ads for manufacturer-backed certified pre-owned (CPO) programs offered through dealerships. While you may be tempted to avoid heading to the dealerâcars for sale by private owners can be found all over Craigslist and other third-party sitesâa CPO vehicle can be a good choice for some buyers.
In the context of a CCTV camera TVL (TV Lines) refers to the horizontal resolution (the maximum number of vertical lines the camera can resolve) of the CCTV camera. TV Lines are the standard measure of an analog TV's Resolution. Rather than represent discrete locations on a grid, as Pixels in a digital Frame do, TV Lines indicate the maximum number of identifiable changes that can be produced along a single (horizontal) Scanline of an analog TV.
TTL means through the lens. Flash metering is through the lens, using the camera's metering system, which looks through the lens you're using. Non-TTL means the flash doesn't communicate with the camera in that way, and instead uses its own light metering system, built into the flash. TTL is better!lkka wrote: It is a bit simplistic to just say that 'TTL is better', because all studio flashes are not TTL and are often quite obviously better sources of light than a small flash unit made by the camera manufacturer.. TTL is a flash metering technology for cameras-not camera lighting.