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| A '''pinhole camera''' is a simple [[camera]] without a [[photographic lens|lens]] and with a single small [[aperture]], a ''[[Pinhole (optics)|pinhole]]'' – effectively a light-proof box with a small hole in one side. Light from a scene passes through this single point and projects an inverted image on the opposite side of the box. The human eye in bright light acts similarly, as do cameras using small apertures.
| | Need to save money when buying at food markets or at web stores? How to save money might be your normal problem when you yourself have plenty of groceries along with other what to purchase to your householdis consumption. Money budgeting is vital to cover all of the household expenses. There are likely a lot of family necessities that want to become purchased as they essential to address your household essential requirements. The very first thing that could come right into the mind for one to save money on your goods is to use coupons.<br><br>When you're shopping for a certain piece that is probably costly, applying coupons for that product can help you spend less and expand your allowance to protect everything that you want to purchase. Just imagine just how many goods you might purchase utilizing the money you had stored through the use of of coupon. Surely, you would appreciate purchasing also it would help you save strain from getting items which you desire. While along with sale, coupons may usually save you big-bucks of income even though it is a tiny piece that you simply could buy.<br><br>Why would you utilize coupons? Probably your basis for employing coupons would be to enable you to try new products with no dangers of wasting your money whenever you think it is unwelcome. Many individuals use coupons for your purpose of seeking new services for an inexpensive value. As an example, they wish to try new all purpose solution, they could check it out without paying a great deal of money. Coupons likewise enable grocery customers to acquire several products for-free. One could get free goods such as toiletries by combining coupons with a selling. In addition, coupons additionally allow you to control your meal charges.<br><br>There are certain coupons for the standard requirements for example food. That is typically wanted to these refined products, stuffed and freezing ingredients you may buy-in food markets. It leaves you more area on your budget on grass fed beef and locally-expanded new and wholefoods.<br><br>In addition to document items, food, and personal care coupons, additionally, there are some that is provided for apparel merchants, regional companies and restaurants. This permits you to treat oneself or your love versions to numerous eateries without wasting a great deal of cash. Thus, coupons for regional providers are significantly helpful if you want to repair factors inside your household even though you are fiscally challenged. With coupons, you get things you need and conserve in the same time. Further, it may also make splurges tremendously economical.<br><br>When you need to purchase products or items which are very expensive such as a branded bags or shoes, coupons could help you afford them. It typically slice the charge of the product you want to buy and provide you the joy of experiencing what exactly you wish to shop.<br><br>There are numerous resources of coupons. The popular of the are the paper inserts and the printable one. They might also be available at the free coupon brochures which can be found at the front end of a specified supermarket or inside your mail, shop pamphlets and those that may be located in the solution. People could also get coupons by checking the net and visiting websites that gives coupons and print it at their homes. There are several food markets that acknowledge several coupons for their stocks and individuals might get make use of this chance to get more items at quite inexpensive prices.<br><br>The economy today makes individuals believe it is hard to manage their residence bills. However, they are often benefited from the use of coupons as it helps them handle their budget. Property parents have nothing to fear of stretching their household budget to coverall in their required charges with all the usage of coupon-clipping. It is a great substitute for tough times once they need to obtain goods due to their house requirements. In-fact there are lots of organizations and shops that offers coupon to entice customers to get their goods. Food shopping couldn't be that tense by giving time to research, produce, and slice and document many coupons that you would need before heading in to the supermarket. More Info: [http://www.cosmeshare.com/activity/p/53120/ jessops discounts]. |
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| Up to a certain point, the smaller the hole, the sharper the image, but the dimmer the projected image. Optimally, the size of the aperture should be 1/100 or less of the distance between it and the projected image.
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| Because a pinhole camera requires a lengthy exposure, its [[shutter (photography)|shutter]] may be manually operated, as with a flap made of light-proof material to cover and uncover the pinhole. Typical exposures range from 5 seconds to several hours.
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| A common use of the pinhole camera is to capture the movement of the sun over a long period of time. This type of photography is called [[Long exposure photography#Solargraphy|solargraphy]].
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| The image may be projected onto a translucent screen for real-time viewing (popular for observing solar eclipses; see also [[camera obscura]]), or can expose [[photographic film]] or a [[charge coupled device]] (CCD). Pinhole cameras with CCDs are often used for [[surveillance]]{{citation needed|date=May 2012}} because they are difficult to detect. | |
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| Pinhole devices provide safety for the eyes when viewing solar eclipses because the event is observed indirectly, the diminished intensity of the pinhole image being harmless compared with the full glare of the [[Sun]] itself.{{Citation needed|date=October 2012}}
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| World Pinhole Day is held on the last Sunday of April.<ref>http://www.bbc.co.uk/news/in-pictures-22150973</ref>
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| == Invention of pinhole camera {{anchor|History|Invention}} ==
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| {{See also|Camera obscura}}
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| In the 10th century AD, Persian scientist [[Ibn al-Haytham]] (Alhazen) wrote about naturally-occurring rudimentary pinhole cameras. For example, light may travel through the slits of wicker baskets or the crossing of tree leaves.<ref>[http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/Light_1.html "Light Through the Ages"].</ref> (The circular dapples on a forest floor, actually pinhole images of the sun, can be seen to have a bite taken out of them during partial solar eclipses opposite to the position of the moon's actual occultation of the sun because of the inverting effect of pinhole lenses.)
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| Alhazen published this idea in the ''[[Book of Optics]]'' in 1021 AD. He improved on the camera after realizing that the smaller the pinhole, the sharper the image (though the less light). He provides the first clear description for construction of a camera obscura (Latin "dark chamber").
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| In the 5th century BC, the [[Mohist]] philosopher [[Mozi]] (墨子) in [[History of China#Ancient China|ancient China]] mentioned the effect of an inverted image forming through a pinhole.<ref name="needham 82">Needham, Joseph (1986). ''Science and Civilization in China: Volume 4, Physics and Physical Technology, Part 1, Physics''. Taipei: Caves Books Ltd. Page 82.</ref> The image of an inverted [[Chinese pagoda]] is mentioned in [[Duan Chengshi]]'s (d. 863) book ''[[Miscellaneous Morsels from Youyang]]'' written during the [[Tang Dynasty]] (618–907).<ref name="needham volume 4 part 1 98">Needham, Joseph (1986). ''Science and Civilization in China: Volume 4, Physics and Physical Technology, Part 1, Physics''. Taipei: Caves Books Ltd. Page 98.</ref> Along with experimenting with the pinhole camera and the [[Burning-glass|burning mirror]] of the ancient Mohists, the [[Song Dynasty]] (960–1279 CE) [[Chinese people|Chinese]] scientist [[Shen Kuo]] (1031–1095) experimented with camera obscura and was the first to establish [[geometrical]] and [[Quantitative property|quantitative]] attributes for it.<ref name="needham volume 4 part 1 98"/>
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| In the 13th century, [[Robert Grosseteste]] and [[Roger Bacon]] commented on the pinhole camera.<ref>[http://www.springerlink.com/index/R2717G210K21R7R2.pdf A reconsideration of Roger Bacon's theory of pinhole images ]</ref> Between 1000 and 1600, men such as Ibn al-Haytham, [[Gemma Frisius]], and [[Giambattista della Porta]] wrote on the pinhole camera, explaining why the images are upside down. | |
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| Around 1600, Giambattista della Porta added a lens to the pinhole camera.<ref>[http://inventors.about.com/library/inventors/blphotography.htm History of Photography and the Camera – Pinhole Camera to Daguerreotype]</ref><ref>http://www-history.mcs.st-andrews.ac.uk/Biographies/Porta.html</ref> It was not until 1850 that a [[Scottish people|Scottish]] scientist by the name of Sir [[David Brewster]] actually took the first photograph with a pinhole camera. Up until recently it was believed that Brewster himself coined the term "Pinhole" in "The Stereoscope"{{Citation needed|date=November 2011}}. The earliest reference to the term "Pinhole" has been traced back to almost a century before Brewster to James Ferguson's Lectures on select Subjects.<ref>{{cite book | url = http://books.google.co.uk/books?id=5w8OAAAAQAAJ&printsec=frontcover#v=onepage&q=&f=false | title = Lectures on select subjects in mechanics, hydrostatics, pneumatics, and optics with the... | author = James Ferguson }}</ref><ref>[http://www.pinhole.cz/en/pinholecameras/whatis.html What is a Pinhole Camera?]</ref> Sir [[William Crookes]] and [[William de Wiveleslie Abney]] were other early photographers to try the pinhole technique.<ref>[http://photo.net/learn/pinhole/pinhole Pinhole photography history]</ref>
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| |image1=Pinhole-camera.svg
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| |alt1=Principle of a pinhole camera: light rays from an object pass through a small hole to form an inverted image.
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| |caption1=Principle of a pinhole camera: light rays from an object pass through a small hole to form an inverted image.
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| |width2=210
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| |image2=IMG 1650 zonsverduistering Malta.JPG
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| |alt2=Holes in the leaf canopy project images of a [[solar eclipse]] on the ground.
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| |caption2=Holes in the leaf canopy project images of a [[solar eclipse]] on the ground.
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| |width3=200
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| |image3=Schießscharten als Lochkamera.JPG
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| |alt3=Ancient pinhole camera effect caused by [[balistraria]]s in the [[Three Castles of Bellinzona|Castelgrande in Bellinzona]]
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| |caption3=Ancient pinhole camera effect caused by [[balistraria]]s in the [[Three Castles of Bellinzona|Castelgrande in Bellinzona]]
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| }}
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| {{-}}
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| == Selection of pinhole size ==
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| Within limits, a smaller pinhole (with a thinner surface that the hole goes through) will result in sharper image [[image resolution|resolution]] because the projected [[circle of confusion]] at the image plane is practically the same size as the pinhole. An extremely small hole, however, can produce significant [[diffraction]] effects and a less clear image due to the wave properties of light.<ref name=hecht>{{cite book|first=Eugene|last=Hecht|title=Optics|year=1998|isbn=0-201-30425-2|chapter=5.7.6 The Camera|edition=3rd}}</ref> Additionally, [[vignetting]] occurs as the diameter of the hole approaches the thickness of the material in which it is punched, because the sides of the hole obstruct the light entering at anything other than 90 degrees.
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| The best pinhole is perfectly round (since irregularities cause higher-order diffraction effects), and in an extremely thin piece of material. Industrially produced pinholes benefit from [[laser]] etching, but a hobbyist can still produce pinholes of sufficiently high quality for photographic work.
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| One method is to start with a sheet of [[brass]] [[shim (engineering)|shim]] or metal reclaimed from an aluminium drinks can or [[tin foil]]/[[aluminum foil]], use fine sand paper to reduce the thickness of the centre of the material to the minimum, before carefully creating a pinhole with a suitably sized needle.
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| A method of calculating the optimal pinhole diameter was first attempted by [[Jozef Maximilián Petzval|Jozef Petzval]]. The crispest image is obtained using a pinhole size determined by the formula<ref>[[Lord Rayleigh|Rayleigh]], (1891) ''[http://idea.uwosh.edu/nick/rayleigh.pdf Lord Rayleigh on Pin-hole Photography]'' in Philosophical Magazine, vol.31, pp. 87–99 presents his formal analysis, but the layman's formula "pinhole radius = √(ƒλ)" appears in Strutt,J.W. Lord Rayleigh (1891) ''Some applications of photography'' in Nature. Vol.44 p.254.</ref>
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| :<math>d=\sqrt{2f\lambda}</math>
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| where ''d'' is pinhole diameter, ''f'' is focal length (distance from pinhole to image plane) and ''λ'' is the [[wavelength]] of light.
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| For standard black-and-white film, a wavelength of light corresponding to yellow-green (550 [[nanometre|nm]]) should yield optimum results. For a pinhole-to-film distance of {{convert|1|in|mm}}, this works out to a pinhole 0.17 mm in diameter.<ref>[http://www.google.com/search?q=sqrt(2*1in*550nm)= Equation for calculation with f=1in, using Google for evaluation]</ref> For 5 cm, the appropriate diameter is 0.23 mm.<ref>[http://www.google.com/search?q=+sqrt(2*5cm*550nm)= Equation for calculation with f=5cm, using Google for evaluation]</ref>
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| The [[depth of field]] is basically [[Infinity|infinite]], but this does not mean that no optical blurring occurs. The infinite depth of field means that image blur depends not on object distance, but on other factors, such as the distance from the aperture to the [[film plane]], the aperture size, and the wavelength(s) of the light source.
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| |image1=LongExposurePinhole.jpg
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| |alt1=An example of a 20 minute exposure taken with a pinhole camera
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| |caption1=An example of a 20 minute exposure taken with a pinhole camera
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| |width2=210
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| |image2=PinholeCameraImage.jpg
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| |alt2=A photograph taken with a pinhole camera using an exposure time of 2s
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| |caption2=A photograph taken with a pinhole camera using an exposure time of 2s
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| == Pinhole camera construction {{anchor|Construction}} ==
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| Pinhole cameras can be handmade by the photographer for a particular purpose. In its simplest form, the photographic pinhole camera can consist of a light-tight box with a pinhole in one end, and a piece of film or photographic paper wedged or taped into the other end.
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| A flap of cardboard with a tape hinge can be used as a shutter.
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| The pinhole may be punched or drilled using a sewing needle or small diameter bit through a piece of tinfoil or thin aluminum or brass sheet.
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| This piece is then taped to the inside of the light-tight box behind a hole cut through the box. A cylindrical oatmeal container may be made into a pinhole camera.
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| Pinhole cameras can be constructed with a sliding film holder or back so the distance between the film and the pinhole can be adjusted.
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| This allows the [[angle of view]] of the camera to be changed and also the effective [[f-stop]] ratio of the camera. Moving the film closer to the pinhole will result in a wide angle field of view and a shorter exposure time.
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| Moving the film farther away from the pinhole will result in a telephoto or narrow angle view and a longer exposure time.
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| Pinhole cameras can also be constructed by replacing the lens assembly in a conventional camera with a pinhole. In particular, compact 35 mm cameras whose lens and focusing assembly have been damaged can be reused as pinhole cameras—maintaining the use of the shutter and film winding mechanisms. As a result of the enormous increase in [[f-number]] while maintaining the same exposure time, one must use a fast film in direct sunshine.
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| Pinholes (homemade or commercial) can be used in place of the lens on an SLR. Use with a digital SLR allows metering and composition by trial and error, and is effectively free, so is a popular way to try pinhole photography.<ref name=PCW>http://www.pcw.co.uk/personal-computer-world/features/2213298/hands-digital-pinhole-camera</ref>
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| Unusual materials have been used to construct pinhole cameras, e.g., a Chinese roast duck.<ref>http://www.urbanphoto.net/blog/2010/11/25/how-a-roast-duck-sees-chinatown/</ref> by Martin Cheung
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| |image1=PinholeCameraAndRelatedSupplies.jpg
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| |alt1=A home-made pinhole camera (on the left), wrapped in black plastic to prevent light leaks, and related developing supplies.
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| |caption1=A home-made pinhole camera (on the left), wrapped in black plastic to prevent light leaks, and related developing supplies.
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| |alt2=A pinhole camera made from an oatmeal box. The pinhole is in the center.
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| |caption2=Same camera made from an oatmeal box without black plastic . The pinhole is in the center.
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| }}
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| == Calculating the f-number & required exposure ==
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| [[File:Pinhole hydrant neg pos.jpg|thumb|right|A [[fire hydrant]] photographed by a pinhole camera made from a shoe box, exposed on photographic paper (top). The length of the exposure was 40 seconds. There is noticeable flaring in the bottom-right corner of the image, likely due to extraneous light entering the camera box.]]
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| The f-number of the camera may be calculated by dividing the distance from the pinhole to the imaging plane (the [[focal length]]) by the diameter of the pinhole. For example, a camera with a 0.5 mm diameter pinhole, and a 50 mm focal length would have an f-number of 50/0.5, or 100 (''f''/100 in conventional notation).
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| Due to the large f-number of a pinhole camera, exposures will often encounter [[reciprocity (photography)|reciprocity]] failure.<ref>http://www.nancybreslin.com/pinholetech.html</ref> Once exposure time has exceeded about 1 second for film or 30 seconds for paper, one must compensate for the breakdown in linear response of the film/paper to intensity of illumination by using longer exposures.
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| Other special features can be built into pinhole cameras such as the ability to take double images, by using multiple pinholes, or the ability to take pictures in [[cylindrical perspective|cylindrical]] or [[spherical perspective]] by curving the film plane.
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| These characteristics could be used for creative purposes.
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| Once considered as an obsolete technique from the early days of [[photography]], pinhole photography is from time to time a trend in artistic photography.
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| Related cameras, image forming devices, or developments from it include Franke's widefield pinhole camera, the [[pinspeck camera]], and the [[pinhead mirror]].
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| [[NASA]] (via the [[NASA Institute for Advanced Concepts]]) has funded initial research into the [[New Worlds Mission]] project, which proposes to use a pinhole camera with a diameter of 10 m and focus length of 200,000 km to image earth sized planets in other star systems.
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| ==Coded apertures==
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| {{Main|Coded aperture}}
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| A non-focusing coded-aperture optical system may be thought of as multiple pinhole cameras in conjunction. By adding pinholes, light throughput and thus sensitivity are increased. However, multiple images are formed, usually requiring computer [[deconvolution]].
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| ==See also==
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| {{Alternative photography}}
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| * [[Pinhole glasses]]
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| * [[Spatial filter]]
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| * [[Zone plate]]
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| * [[Dirkon]]
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| * [[Ibn al-Haytham]]
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| * [[Fox Talbot]]
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| * [[Wolf Howard]]
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| * [[Billy Childish]]
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| * [[Jesse Richards]]
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| * [[Pinhole camera model]]
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| * [[Nautilus]] (its [[pinhole eye]] functions as a camera)
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| * [[Pinhole occluder]], a similar device used by ophthalmologists
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| * [[Camera obscura]], uses the same principle as a pinhole camera
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| * [[The Great Picture]]
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| == References {{anchor|Notes|References}} ==
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| {{Reflist}}
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| ==External links==
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| {{Commons category|Pinhole photography}}
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| * [http://www.behance.net/gallery/PICTORIALISM-Winter-Pinhole-Photography/897715 Pinhole Photography by Vladimir Zivkovic]
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| * [http://www.pinholeday.org/gallery/index.php Worldwide Pinhole Photography Day website]
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| * [http://www.alistairscott.com/howto/pinhole/ An easy way to convert a DSLR to a pinhole camera]
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| * [http://www.mrpinhole.com/ Pinhole Photography and Camera Design Calculators]
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| * [http://www.precinemahistory.net/ Illustrated history of cinematography]
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| * [http://www.kodak.com/global/en/consumer/education/lessonPlans/pinholeCamera/pinholeCanBox.shtml How to Make and Use a Pinhole Camera]
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| * [http://watch.opb.org/video/2364990891 Oregon Art Beat: Pinhole Photos by Zeb Andrews]
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| {{Photography}}
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| {{DEFAULTSORT:Pinhole Camera}}
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| [[Category:Cameras by type]]
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Need to save money when buying at food markets or at web stores? How to save money might be your normal problem when you yourself have plenty of groceries along with other what to purchase to your householdis consumption. Money budgeting is vital to cover all of the household expenses. There are likely a lot of family necessities that want to become purchased as they essential to address your household essential requirements. The very first thing that could come right into the mind for one to save money on your goods is to use coupons.
When you're shopping for a certain piece that is probably costly, applying coupons for that product can help you spend less and expand your allowance to protect everything that you want to purchase. Just imagine just how many goods you might purchase utilizing the money you had stored through the use of of coupon. Surely, you would appreciate purchasing also it would help you save strain from getting items which you desire. While along with sale, coupons may usually save you big-bucks of income even though it is a tiny piece that you simply could buy.
Why would you utilize coupons? Probably your basis for employing coupons would be to enable you to try new products with no dangers of wasting your money whenever you think it is unwelcome. Many individuals use coupons for your purpose of seeking new services for an inexpensive value. As an example, they wish to try new all purpose solution, they could check it out without paying a great deal of money. Coupons likewise enable grocery customers to acquire several products for-free. One could get free goods such as toiletries by combining coupons with a selling. In addition, coupons additionally allow you to control your meal charges.
There are certain coupons for the standard requirements for example food. That is typically wanted to these refined products, stuffed and freezing ingredients you may buy-in food markets. It leaves you more area on your budget on grass fed beef and locally-expanded new and wholefoods.
In addition to document items, food, and personal care coupons, additionally, there are some that is provided for apparel merchants, regional companies and restaurants. This permits you to treat oneself or your love versions to numerous eateries without wasting a great deal of cash. Thus, coupons for regional providers are significantly helpful if you want to repair factors inside your household even though you are fiscally challenged. With coupons, you get things you need and conserve in the same time. Further, it may also make splurges tremendously economical.
When you need to purchase products or items which are very expensive such as a branded bags or shoes, coupons could help you afford them. It typically slice the charge of the product you want to buy and provide you the joy of experiencing what exactly you wish to shop.
There are numerous resources of coupons. The popular of the are the paper inserts and the printable one. They might also be available at the free coupon brochures which can be found at the front end of a specified supermarket or inside your mail, shop pamphlets and those that may be located in the solution. People could also get coupons by checking the net and visiting websites that gives coupons and print it at their homes. There are several food markets that acknowledge several coupons for their stocks and individuals might get make use of this chance to get more items at quite inexpensive prices.
The economy today makes individuals believe it is hard to manage their residence bills. However, they are often benefited from the use of coupons as it helps them handle their budget. Property parents have nothing to fear of stretching their household budget to coverall in their required charges with all the usage of coupon-clipping. It is a great substitute for tough times once they need to obtain goods due to their house requirements. In-fact there are lots of organizations and shops that offers coupon to entice customers to get their goods. Food shopping couldn't be that tense by giving time to research, produce, and slice and document many coupons that you would need before heading in to the supermarket. More Info: jessops discounts.