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Extension tubes are sometimes confused with teleconverters, an optical component (i.e., containing lenses) designed to increase effective focal length. A close-up lens also enables focusing closer for macro photography but, unlike an extension tube, a close-up lens actually is an optical element.
Many macro lenses are characterised by a high amount of chromatic aberration, especially when using reversed-lens, extension tube or close-up lens. Some macro lenses, called apochromatic lenses, are designed to better control this, such as the Laowa 100mm f/2.8 2x Ultra Macro APO and the Sigma APO MACRO 150mm F2.8.
That distance is sometimes given on the filter in millimeters. A +3 close-up lens has a maximal working distance of 0.333 m or 333 mm. The magnification is the focal distance of the objective lens (f) divided by the focal distance of the close-up lens; i.e., the focal distance of the objective lens (in meters) multiplied by the diopter value (D) of the close-up lens:
iMacros is a browser-based application for macro recording, editing and playback for web automation and testing. It is provided as a standalone application and extension for Mozilla Firefox , Google Chrome , and Internet Explorer web browsers .
A macro recorder is software that records macros for playback at a later time. The main advantage of using a macro recorder is that it allows a user to easily perform complex operations much faster and with less effort without requiring custom computer programming or scripting.
This design is also used in JPEG and most other macroblock-based video codecs with a fixed transform block size, such as MPEG-1 Part 2 and H.262/MPEG-2 Part 2. In other chroma subsampling formats, e.g. 4:0:0, 4:2:2, or 4:4:4, the number of chroma samples in a macroblock will be smaller or larger, and the grouping of chroma samples into blocks ...
jEdit's macro editor. In computer programming, a macro (short for "macro instruction"; from Greek μακρο- 'long, large' [1]) is a rule or pattern that specifies how a certain input should be mapped to a replacement output. Applying a macro to an input is known as macro expansion.
Photomultiplier tubes (photomultipliers or PMTs for short) are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum. They are members of the class of vacuum tubes , more specifically vacuum phototubes .