Although it may be only in school that you are asked to write a specifically descriptive essay, description is an important element in many kinds of writing. Description embedded in an argument paper, for example, may be intended to make a position more persuasive. However, in this TIP Sheet we will discuss the descriptive essay as it is commonly assigned by instructors as an exercise in organizing sensory information and choosing vivid details. If you choose "showing" words, those that supply vivid sensory details appropriate to your subject and purpose, you will succeed in showing rather than telling.
Same Display Dimensions As a corollary, Equivalent lenses are lenses that produce Equivalent photos on the format they are used on which means they will have the same AOV angle of view and the same aperture diameter.
The focal lengths all have the same [diagonal] AOVso we say the focal lengths are equivalent.
The same total amount of light falls on the sensor for the same equivalent relative aperture and same exposure time, so we say the exposures are equivalent.
The photos will have the same lightness for the same equivalent exposure and equivalent ISO setting, so we say the ISO settings are equivalent. An important consequence of the same aperture entrance pupil diameter is that the DOF and diffraction will also be the same for a given perspective, framing, display size, viewing distance, and visual acuity.
In addition, since the exposure times are the same, the same total amount of light will fall on the sensor for all systems with a given scene luminance and lens transmissionwhich means the photos will have the same noise if the sensors are equally efficient.
Of course, sensors are not equally efficient although often, but not always, close for a given generationnor are all lenses proportionally sharp, have the same color, bokeh, distortion, or flare characteristics, nor do all sensors have the same pixel count, CFA, and AA filter.
Indeed, according to Webster'sthe primary definition of "equivalent" is: Equality of other visual properties, such as noise, detail, etc. The second and third definitions of "equivalent" also fits: On the other hand, sensors of the same generation are usually pretty close in terms of efficiency see here for quite a few examples.
Still, there are other issues to consider, such as color and distortion although these two can usually be corrected for in processingbokeh, lens flare, etc.
So while differences in the technology may well make for differences that matter more than one or more of the parameters of Equivalence, Equivalent photos will typically be the closest in appearance more so, of course, when the sensors are of the same generation.
The larger the photo is displayed, the more extreme the processing, and the lower the amount of light that makes up the photo, the more obvious the role that differences in technology will play. In addition, there is a small niggle in the parameter of "same framing" for systems with different aspect ratios e.
We can either crop one image to the the aspect ratio of the other or crop both to a common aspect ratio or compare at the same AOV and display with the same diagonal measurement.
The details of this are discussed at the end of this section. It is important to note that Equivalent photos on different formats will not have the same exposureand this is the source of most all resistance to the concept.
The reason is quite simple: The same total amount of light will fall on the sensor for Equivalent photos which results in a lower density of light exposure on a larger sensor. Many feel that exposure has been usurped with DOFbut this reflects not only a lack of understanding of what exposure actually is, but how much of a role DOF plays in a photo, even if DOF, per se, is not a consideration.
While the artistic value of DOF is subjective, the fact is that both the total light falling on the sensor and the DOF are functions of the aperture diameter. Larger aperture diameters admit more light, but they also introduce more aberrations from the lens.
Thus, DOF, noise, and sharpness are all intrinsically related through the aperture of the lens.Here are the sections you will find: Section 1: What I'll be discussing in this how-to essay; Section 2: Understand who or what you're hiding from.
The Purdue University Online Writing Lab serves writers from around the world and the Purdue University Writing Lab helps writers on Purdue's campus. Expository Essay Topic Ideas, Writing Tips, and Sample Essays.
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Albrecht Dürer: The Genius with a Great Soul. Albrecht Dürer was not only the greatest artist of the Northern Renaissance, but also a unique personality, his genius coexisting with a pure, noble character.
One of the common features of an epic is the "fabulous loci" for the hero to visit. Fantasy novels can have some loci that are quite pretty or terrifying, but science .