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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.
| | She was hoping for one baby, and the news that we are having two is a double blessing. Pregnancy planning is something very important in today's world. A routine exercise of 30 minutes per day in a week is alright. When trying to get pregnant, go for having sex thrice each week that will deal with any kind of doubtful times if you aren't particularly certain if you ovulated. There are plenty of unknown hints and tips that can make playing of the game The Sims 2 a lot more fun. <br><br>These are not very dependable indications of ovulation, nonetheless, as a result of they will have many causes. Sims are able to have sex with members of the opposite sex as well as members of the same sex. Even though it sounds crazy, the best option would be to give teens some form of birth control and actually allow them to have sex in their house. If you think you can't have a baby, it is possible that your body will act that way. The mobility of the sperm can be affected by the lubricants. <br><br>The recommended dosage is 500mg of vitamin C supplements daily, but you can go as high as 1000mg, but do not exceed more than 1000mg per day. Epididymals obstruction is defined as the blockage of the passage of sperm to **** leading to low sperm count and increases the risk of infertility. This has something to do with the life spans of the female egg and the male sperm. Here are some fertility tips to get pregnant as fast as possible. Snooki's son Lorenzo is going to have a BFF in Baby Mathews, that's for sure. <br><br>Normally, it takes several months or sometimes even years to get pregnant. It is just a matter of finding the perfect remedy for your situation. When you are in great shape, your body can do what it is designed to do without a problem. It was an interesting spiritual cleansing and as with all spiritual journeys, it just might have worked if there is enough belief. Drink lots of water to rid off toxins in your body. <br><br>So for example, in case you ovulate on day 14 you'd probably remain away from sex on day 11-12. If a couple decides to go for consultation of medical experts then first thing is to fix up an appointment with infertility specialist. When to commence testing for ovulation with your Home-Check Instant Ovulation test Kit. If you're stressed out your body knows this, and could be working against you. Having twins has something to do with your family history of having twins.<br><br>Should you have just about any queries regarding where by along with how you can use [http://www.quebec-1759.info/ how common is it to get pregnant on the pill], it is possible to contact us at our own web site. |
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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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| {{-}}
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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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She was hoping for one baby, and the news that we are having two is a double blessing. Pregnancy planning is something very important in today's world. A routine exercise of 30 minutes per day in a week is alright. When trying to get pregnant, go for having sex thrice each week that will deal with any kind of doubtful times if you aren't particularly certain if you ovulated. There are plenty of unknown hints and tips that can make playing of the game The Sims 2 a lot more fun.
These are not very dependable indications of ovulation, nonetheless, as a result of they will have many causes. Sims are able to have sex with members of the opposite sex as well as members of the same sex. Even though it sounds crazy, the best option would be to give teens some form of birth control and actually allow them to have sex in their house. If you think you can't have a baby, it is possible that your body will act that way. The mobility of the sperm can be affected by the lubricants.
The recommended dosage is 500mg of vitamin C supplements daily, but you can go as high as 1000mg, but do not exceed more than 1000mg per day. Epididymals obstruction is defined as the blockage of the passage of sperm to **** leading to low sperm count and increases the risk of infertility. This has something to do with the life spans of the female egg and the male sperm. Here are some fertility tips to get pregnant as fast as possible. Snooki's son Lorenzo is going to have a BFF in Baby Mathews, that's for sure.
Normally, it takes several months or sometimes even years to get pregnant. It is just a matter of finding the perfect remedy for your situation. When you are in great shape, your body can do what it is designed to do without a problem. It was an interesting spiritual cleansing and as with all spiritual journeys, it just might have worked if there is enough belief. Drink lots of water to rid off toxins in your body.
So for example, in case you ovulate on day 14 you'd probably remain away from sex on day 11-12. If a couple decides to go for consultation of medical experts then first thing is to fix up an appointment with infertility specialist. When to commence testing for ovulation with your Home-Check Instant Ovulation test Kit. If you're stressed out your body knows this, and could be working against you. Having twins has something to do with your family history of having twins.
Should you have just about any queries regarding where by along with how you can use how common is it to get pregnant on the pill, it is possible to contact us at our own web site.