Search results
Results from the WOW.Com Content Network
Maddox wing. The Maddox Wing is an instrument utilized by ophthalmologists, orthoptists and optometrists in the measurement of strabismus (misalignment of the eyes; commonly referred to as a squint or lazy eye by the lay person). It is a quantitative and subjective method of measuring the size of a strabismic deviation by dissociation of the ...
The lens has an EF mount and works with EOS film and digital cameras. The lens comes in two different versions: Canon EF 70–210mm f/4 AFD (1987–1990) Canon EF 70–210mm f/3.5–4.5 USM (introduced 1990) The variable-aperture USM model utilizes a rotating ring instead of a push-pull system for adjusting zoom. The lens was superseded by the ...
Prism dioptres. Prism correction is commonly specified in prism dioptres, a unit of angular measurement that is loosely related to the dioptre. Prism dioptres are represented by the Greek symbol delta (Δ) in superscript. A prism of power 1 Δ would produce 1 unit of displacement for an object held 100 units from the prism. [2]
Macro photograph of a common yellow dung fly ( Scathophaga stercoraria) made using a lens at its maximum 1:1 reproduction ratio, and an 18×24mm image sensor, the on-screen display of the photograph results in a greater than life-size image. Headshot of a dragonfly taken with a 100 mm macro lens coupled with a 50 mm lens in reverse at the end.
The Sigma 18-50mm f/2.8 EX DC Macro is a wide to normal angle, zoom lens made by the Sigma Corporation . The lens is produced in Canon EF mount, Four Thirds System, Nikon F-mount, Pentax K mount, the SA mount, and the Sony/Minolta AF Mount varieties, all have the same optical formula. The lens is designed for digital crop DSLR with an APS-C ...
The first auto-everything 35mm point-and-shoot camera with built-in zoom lens, the camera type that dominated the 1990s, was the Asahi Optical Pentax IQZoom (1987, Japan) with Pentax Zoom 35-70mm f/3.5-6.7 Tele-Macro. The next landmark zoom was the Sigma 21-35mm f/3.5-4 (Japan) of 1981. It was the first super-wide angle zoom lens for still ...
Esophoria is an eye condition involving inward deviation of the eye, usually due to extra-ocular muscle imbalance. It is a type of heterophoria. Cause. Causes include: Refractive errors; Divergence insufficiency; Convergence excess; this can be due to nerve, muscle, congenital or mechanical anomalies.
Canon EF 24–70mm f/2.8L lens with hood (EW-83F) The Canon EF 24–70mm lens is a family of professional EF mount wide -to- normal zoom lenses manufactured and sold by Canon. The first of the family, the EF 24–70mm f/2.8L, was introduced in 2002 to replace the well-regarded 28–70mm f/2.8L. Two later versions were announced in 2012.
Canon EF 70–200mm f/2.8L IS II USM with lens hood. The EF 70–200mm lenses are a group of telephoto zoom full-frame lenses made by Canon. The lenses have an EF mount to work with the EOS line of cameras. The lens comes in seven different versions, all of which have fixed maximum aperture at all focal lengths, and are L-series lenses.
58mm. The Sigma 70-300mm F4-5.6 APO DG Macro lens is a consumer-level, telephoto zoom lens made by Sigma Corporation. [1] Different versions of this lens are produced that work with cameras from Canon, Nikon, Pentax, Konica Minolta, Sony and Sigma. Additionally, Olympus' 70–300 f/4–5.6 lens for Four-Thirds has the same optical design and ...