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Diffraction Limited Photography: Pixel Size, Aperture and Airy Disks

Diffraction Limited Photography: Pixel Size, Aperture and Airy Disks
Diffraction is an optical effect which limits the total resolution of your photography — no matter how many megapixels your camera may have. It happens because light begins to disperse or "diffract" when passing through a small opening (such as your camera's aperture). This effect is normally negligible, since smaller apertures often improve sharpness by minimizing lens aberrations. However, for sufficiently small apertures, this strategy becomes counterproductive — at which point your camera is said to have become diffraction limited. Knowing this limit can help maximize detail, and avoid an unnecessarily long exposure or high ISO speed. Light rays passing through a small aperture will begin to diverge and interfere with one another. Large Aperture Small Aperture Since the divergent rays now travel different distances, some move out of phase and begin to interfere with each other — adding in some places and partially or completely canceling out in others. Diffraction Pattern Airy Disk Related:  Camera Optics Theory

Photon Nomenclature[edit] In 1900, Max Planck was working on black-body radiation and suggested that the energy in electromagnetic waves could only be released in "packets" of energy. In his 1901 article [4] in Annalen der Physik he called these packets "energy elements". Physical properties[edit] The cone shows possible values of wave 4-vector of a photon. A photon is massless,[Note 2] has no electric charge,[13] and is stable. Photons are emitted in many natural processes. The energy and momentum of a photon depend only on its frequency (ν) or inversely, its wavelength (λ): where k is the wave vector (where the wave number k = |k| = 2π/λ), ω = 2πν is the angular frequency, and ħ = h/2π is the reduced Planck constant.[17] Since p points in the direction of the photon's propagation, the magnitude of the momentum is The classical formulae for the energy and momentum of electromagnetic radiation can be re-expressed in terms of photon events. Experimental checks on photon mass[edit]

Understanding Lens Diffraction This is not a comprehensive treatise on the subject of lens diffraction effects. Rather, it's purpose is to bring to the attention of photographers who may not be aware of the issue that there is no free lunch when it comes to achieving greater depth of field though stopping down. Every photographer wants both maximum resolution and maximum depth of field. But unfortunately these two demands can be mutually exclusive. As you stop down the aperture on a lens the light passing through tends to diffract, reducing sharpness, though DOF is increased. This is why it's important to test each lens in your arsenal for the point at which they are visibly affected by diffraction. After recently purchasing four ultra-high performance Rodenstock medium format lenses for use with a 39 Megapixel Phase One P45 back, I was curious to see whether Rodenstock's claim that these lenses were diffraction limited would hold true.

High Intensity Interval Training: Sprint Interval Workout This sprint interval workout is a type high intensity interval training (HIIT) that helps build endurance, increase your anaerobic threshold and burn more calories and fat both during and after your workout. For this workout, you'll have a longer warm up (10 minutes) before going into 4 all-out sprints at a Level 9 on this perceived exertion chart for 30 seconds each. Between each sprint, you'll recover at an easy pace for 4.5 minutes, giving you plenty of time to get ready for the next sprint. Keep in mind that all-out effort is very challenging, so modify the sprint intervals as needed to fit your fitness level and goals.

Curso de Cromado, Niquelado, Cobrizado, Cromo en Plásticos Lens Genealogy LENS GENEALOGY Part 1by Roger Cicala Where do new lens designs come from?I knew that today’s lenses are all designed using computer programs, but I was surprised to find new lenses aren’t designed from scratch. So camera lenses, like Darwin’s finches, obey a very strict “survival of the fittest” law. Even knowing this, when I wrote a series of articles on the development of camera lenses, I was amazed to find that virtually every camera lens in use today can trace its heritage back to one of five lenses, four of which were developed by 1900. Does the pedigree of a lens matter? Knowing the ancestry of a lens can be interesting from a historical standpoint. Early Lenses DesignsThe first lenses were rather simple things. A mensicus lens (left) and an achromatic doublet After the invention of the Daguerrotype camera lens design improved rapidly and literally hundreds of photographic lenses had been marketed by the early 1900s. The Lens Family Tree The Petzval Portrait lens Advantages: Duh!

Thomas Young Thomas Young (13 de junio de 1773 – 10 de mayo, 1829) fue un científico inglés. Young es célebre por su experimento de la doble rendija que mostraba la naturaleza ondulatoria de la luz y por haber ayudado a descifrar los jeroglíficos egipcios a partir de la piedra Rosetta. Biografía[editar] Young pertenecía a una familia cuáquera de Milverton, Somerset, donde nació en 1773 siendo el más joven de diez hermanos. Comenzó estudios de medicina en Londres en 1792 mudándose poco después a Edimburgo (1794) y Gotinga (1795) donde obtuvo el grado de doctor en física en 1796. Obra científica[editar] Durante sus años como profesor de la Royal Institution realizó 91 conferencias sobre muy diversos temas. Experimento de la doble rendija[editar] Young es conocido por sus experiencias de interferencia y difracción de la luz demostrando la naturaleza ondulatoria de ésta. Módulo de Young[editar] Estudios sobre la visión[editar] Thomas Young fue también el fundador de la óptica fisiológica. Bibliografía[editar]

How to Disagree March 2008 The web is turning writing into a conversation. Twenty years ago, writers wrote and readers read. The web lets readers respond, and increasingly they do—in comment threads, on forums, and in their own blog posts. Many who respond to something disagree with it. That's to be expected. The result is there's a lot more disagreeing going on, especially measured by the word. If we're all going to be disagreeing more, we should be careful to do it well. DH0. This is the lowest form of disagreement, and probably also the most common. u r a fag!!!!!!!!!! But it's important to realize that more articulate name-calling has just as little weight. The author is a self-important dilettante. is really nothing more than a pretentious version of "u r a fag." DH1. An ad hominem attack is not quite as weak as mere name-calling. Of course he would say that. This wouldn't refute the author's argument, but it may at least be relevant to the case. DH2. DH3. DH4. DH5. DH6. What It Means Related:

Cape Fear Press DSLR Magnification By: Nick Rains We live in ‘interesting times’. Not since colour film was introduced has so much controversy raged about photography. The Internet has allowed vast global discussions to ebb and flow like never before and whilst this is great in some respects, the downside is that there is a whole lot of misinformation floating around. Problem: How to sift the simple facts and truths from the myths and rumours? Answer: With a basic knowledge of certain aspects of photography, especially basic lens theory. Rainbow Lorikeet Canon D60 with Canon 300/2.8L IS lens and 2x Extender (960mm Equivalent Focal Length). The ‘Focal Length Multiplier’ is one of the most easily misunderstood characteristics of the some of the new breeds of DSLR and so I would like to offer a brief look at this aspect of digital imaging and attempt to lay to rest some of the myths. OK, firstly, when you put a 300mm lens on a D60 you do NOT get a 480mm lens – it is still a 300mm lens. Here is the rub. All is not gloomy though.

TAMPL SUMMER 97 Several different optical phenomena are studied through the Microscale Reflectance Spectrometer: Thin-Film Interference occurs only in the presence of thin-films. The required condition is that the thickness of the film is on the same order of magnitude as the wavelength of incident light. Diffractionoccurs when there are surface roughness with regular patterns. Non-planer Specular Reflection is a case where thin-film interference combines with a repeated surface pattern with pattern size much larger than the wavelengths of incident light. These optical phenomena can be observed in many human-made and organic thin-films. A Numerical Model was developed to predict the spectral reflectivities of simple thin-film structures. Thin-film Interference Thin-films are found in many applications, including optical coatings, protective coatings, and microelectronic chips. The changes in spectral optical properties are caused by thin-film interference. Diffraction Non-planar Specular Reflection

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