Invention of pinhole camera

Camera obscura As far back as the 4th century BC, Greeks such as Aristotle and Euclid wrote on naturally-occurring rudimentary pinhole cameras. For example, light may travel through the slits of wicker baskets or the crossing of tree leaves. It was the 10th-century Arab physicist, astronomer and mathematician, Ibn al-Haytham (Alhazen), who published this idea in the Book of Optics in 1021 AD. When Ibn al-Haytham began experimenting with the camera obscura, he himself stated, Et nos non inventimus ita, “we did not invent this”. 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 (Lat. dark chamber). As a side benefit of his invention, he was credited with being first man to shift physics from a philosophical to an experimental basis. In the 5th century BC, the Mohist philosopher Mo Jing () in ancient China mentioned the effect of an inverted image forming through a pinhole. 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 (618907). Along with experimenting with the pinhole camera and the burning mirror of the ancient Mohists, the Song Dynasty (9601279 AD) Chinese scientist Shen Kuo (10311095) experimented with camera obscura and was the first to establish geometrical and quantitative attributes for it. Ancient pinhole camera effect caused by balistrarias in the Castelgrande in Bellinzona In the 13th century, Robert Grosseteste and Roger Bacon commented on the pinhole camera. 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. 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. Around 1600, Giambattista della Porta added a lens to the pinhole camera. It was not until 1850 that a 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”. 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. Sir William Crookes and William de Wiveleslie Abney were other early photographers to try the pinhole technique. Selection of pinhole size Generally, a smaller pinhole (with a thinner surface that the hole goes through) will result in sharper image resolution as the projected circle of confusion is smaller at the image plane. The thinner and smaller, the more resolution. This is why a lot of pinhole instructions tell you to sand the surface the hole is in. An extremely small hole, however, can produce significant diffraction effects and a less clear image due to the wave properties of light. Additionally, as the diameter of the hole approaches the thickness of the material in which it is punched, significant vignetting occurs, as less light reaches the edges of the image. This is due to the sides of the hole shading the light coming in at anything other than 90 degrees. 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. An example of a 20 minute exposure taken with a pinhole camera A photograph taken with a pinhole camera using an exposure time of 2s Some examples of photographs taken using a pinhole camera. One often quoted method is to start with a sheet of brass 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 sanding away the burrs on either side & rotating the pin as it glides in and out in order to produce a smooth circular hole. A method of calculating the optimal pinhole diameter was first attempted by Jozef Petzval. The formula used today was evolved by Lord Rayleigh: where d is diameter, f is focal length (distance from pinhole to focal plane) and is the wavelength of light. For standard black-and-white film, a wavelength of light corresponding to yellow-green (550 nm) should yield optimum results. (For a pinhole-to-film distance of 1 inch (25 mm), this works out to a pinhole 0.22 mm in diameter. For 5 cm, the appropriate diameter is 0.32 mm. The depth of field is basically 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. Pinhole camera construction Pinhole cameras are usually handmade by the photographer for a particular purpose. In its simplest form, the photographic pinhole camera consists 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. A flap of cardboard with a tape hinge can be used as a shutter. The pinhole is usually punched or drilled using a sewing needle or small diameter bit through a piece of tinfoil or thin aluminum or brass sheet. This piece is then taped to the inside of the light tight box behind a hole cut through the box. An oatmeal box can be made into an excellent pinhole camera. Pinhole cameras are often constructed with a sliding film holder or back so that the distance between the film and the pinhole can be adjusted. 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. Moving the film farther away from the pinhole will result in a telephoto or narrow angle view and a longer exposure time. 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 has been damaged can be reused as pinhole camerasaintaining 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. 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. Calculating the f-number & required exposure A pinhole camera made from an oatmeal box. The pinhole is in the centre. The black plastic which normally surrounds this camera (see picture above) has been removed. 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. 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 0.02 inch (0.5 mm) diameter pinhole, and a 2 inch (50 mm) focal length would have an f-number of 2/0.02 (50/0.5), or 100 (f/100 in conventional notation). Due to the large f-number of a pinhole camera, exposures will often encounter reciprocity failure. 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. 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 or spherical perspective by curving the film plane. These characteristics could be used for creative purposes. Once considered as an obsolete technique from the early days of photography, pinhole photography is from time to time a trend in artistic photography. Related cameras, image forming devices, or developments from it include Franke’s widefield pinhole camera, the pinspeck camera, and the pinhead mirror. 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. World’s largest pinhole camera In an abandoned F-18 hangar at the closed El Toro fighter base in Irvine, California, a team of six photographer artists and an army of assistants created the world’s largest pinhole camera, using 1 miles of 2 inches (5.1 cm) wide black Gorilla Tape and 40 US gallons (150 l) of black spray paint to make the hangar light-tight. The aim was to make a black-and-white negative print of the Marine Corps air station with its control tower and runways, with the San Joaquin Hills in the background. The purpose was to subscribe to the Legacy Project, a photographic compilation and record of the airfield’s history before it is transformed into a giant urban park, as well as to demonstrate to the digital world the value of print making the 168-year-old way. A huge piece of muslin cloth was made light sensitive by coating it with 80 litres of gelatin silver halide. and it was hung from the ceiling at a distance of about 80 feet (24 m) from a pinhole, just under .25 inches (0.64 cm) in diameter, situated 15 feet (4.6 m) above ground level in the wall. The distance between the pinhole and the cloth was determined to be 80 feet (24 m) for best coverage, and the exposure time was calculated at 35 minutes. The opaque negative image print was developed in an Olympic-swimming-pool-size tray with 600 US gallons (2,300 l) of traditional developer and 1,200 US gallons (4,500 l) of fixer, and was washed using fire hoses attached to two fire hydrants. The resulting finished print was nearly 108 ft (33 m) wide and 85 ft (26 m) high and was exhibited for the first time at the Art Center College of Design in Pasadena, California, on September 6, 2007. Read more: http://www.articlefield.com/34809/pinhole-camera-808nm-diode-laser-k81s08m-20-00w-fiber-dense-array-kctf-16/#ixzz1BOFGZyvu

Worlds Beautiful Islands: Philippines Islands - Boracay

Worlds Beautiful Islands: Philippines Islands - Boracay: "Philippines Islands - BoracayBoracay is a beautiful island of the Philippines located approximately 315 km (20..."

PHOTOMANIPULATION

Photo manipulation is the application of image editing techniques to photographs in order to create an illusion or deception (in contrast to mere enhancement or correction), through analog or digital means


Types of digital photo manipulationIn digital editing, photographs are usually taken with a digital camera and input directly into a computer. Transparencies, negatives or printed photographs may also be digitized using a scanner, or images may be obtained from stock photography databases. With the advent of computers, graphics tablets, and digital cameras, the term image editing encompasses everything that can be done to a photo, whether in a darkroom or on a computer. Photo manipulation is often much more explicit than subtle alterations to color balance or contrast and may involve overlaying a head onto a different body or changing a sign's text, for example. Image editing software can be used to apply effects and warp an image until the desired result is achieved. The resulting image may have little or no resemblance to the photo (or photos in the case of compositing) from which it originated. Today, photo manipulation is widely accepted as an art-form.




There are several subtypes of digital image-retouching:



Technical retouching

Manipulation for photo restauration or enhancement (adjusting colors / contrast / white balance (i.e. gradational retouching), sharpness, removing elements or visible flaws on skin or materials, ...)



Creative retouching

Used as an art form or for commercial use to create more sleek and interesting creative images for advertisements. Creative retouching could be manipulation for fashion, beauty or advertising photography such as pack-shots (which could also be considered inherently technical retouching in regards to package dimensions and wrap-around factors) One of the most prominent disciplines in creative retouching is image-compositing. Here, the digital artist uses multiple photos to create a single composited image. Today, 3D elements are used more and more to add extra elements or even locations and backgrounds. This kind of image composition is widely used when conventional photography would be technically too difficult or impossible to shoot on location or in studio.


GALERY BY ELENA DUDINA

  http://4bb59b8b.linkbucks.com/  

Canon Pixma Sound Sculptures

(related to sSound sculpture ound art and sound installation) is an intermedia and time based artform in which sculpture or any kind of art object produces sound, or the reverse (in the sense that sound is manipulated in such a way as to create a sculptural as opposed to temporal form or mass). Most often sound sculpture artists were primarily either visual artists or composers, not having started out directly making sound sculpture.


Cymatics and kinetic art has influenced sound sculpture. Sound sculpture is sometimes site-specific.

Canon Pixma Sound Sculptures


 
 
 

 
 

 
 

Canoes At Lake Moraine - Photograph at BetterPhoto.com

Canoes At Lake Moraine - Photograph at BetterPhoto.com

Spirit dove. Using glowing edge Tutorial

Spirit dove



In this tutorial, we are going to create a dove like spirit bursting out of a woman's body amidst the cloudy sky. This tutorial uses a basic filter of glowing edge to create those shiny outlines engulfing the objects.


These are the images that we are going to use:

                                           Woman: 280543 © Galina Barskaya 123RF.com

                                                        Dove: 7478307 © Irina Tischenko 123RF.com

                                            Clouds 1: 633425 © Feng Yu 123RF.com












                                           

                                            Clouds 2: 2954467 © Chris Hill 123RF.com

                                            Stars: 3404631 © Martin Benes 123RF.com




Start off with a basic black background, and have all of the elements nicely masked of its background. Place it accordingly.

  Hide the dove for now as we will be focusing on the woman. Since we will be needing multiple instances of the woman layer, duplicate it a few times. 
 
 
 

Before we proceed, here's a rough guideline on layer accordance. We should have 4 duplicates (for now), namely base object > 'Screen' outline > 'Overlay' outline > Color mode layer.

Take one of the duplicate on top and apply Glowing edges.

Change this to 'Screen' blend mode. This will be our 'Screen' outline layer, on top of base model

Apply the same filter to another duplicate and this time change to 'Overlay' blend mode, on top of 'Screen' outline layer

Use the 3rd duplicate and change it to 'Color' mode. This will give color to the glowing lines. Positioned at the top most layer.

Certain glowing lines are too thick around the face. So mask it off at both of the layers ('Screen' & 'Overlay' outline).

Adding flames around the body


For the next step, duplicate another instance of the base model and put the duplicate on top. Apply a 'Outer glow' layer style.

Create a new layer just above the 'Outer glow' layer, and create a difference cloud rendering (apply a couple of times to make the lines more extreme).

Set its blend mode to 'Color dodge', and erase areas so that the effect only falls around the model. We can use the 'Outer glow' layer's setting to control how far the flame is extruding (the bigger the glow size, the bigger the flame radius

Once done, we can group these layers together, namely 'woman'. An overview of the layers involved:

The next series of mini-steps is what I've done to create those stretchy bursting lines. This section is merely a rough guide, albeit an unorthodox one to achieve the desired effect.




1.Copy a portion of glowing lines. Preferably from the flowing cloth area. These lines are desaturated, warped, and smudged.



2.Duplicate another copy, blend it in, and smudge in more.



3.Third duplicate isn't desaturated, but blurred, and smudge even more. Blended it as 'Screen' mode.



4.Combine all the above.



5.Duplicate the combined and applied warping and further smudging it to a stretchy curvy state.



6.Mask off excessive areas.



7.Select base model, 'Screen' blend mode, and 'Overlay' blend mode. Duplicate a copy each. Combine them and start smudging the body area upwards. Change this layer to 'Color dodge' blende mode, and erase excessive areas.



8.Result.

We can now place that effect on top of the group 'woman'

With the layer 'base model' selected, mask of the areas connecting the effect and the body

Add in light rays that are seen exiting the eyes and mouth. Mix motion blur and transform tool to achieve the desired rays.

The dove effect is of similar steps to the above. Duplicate layers

Apply glowing edge.

Set it to 'Screen' blend mode

Duplicate and Set it to 'Color dodge' to intensify the glowing lines.

Have another copy set to 'Color' blend mode above all.

Mask and drag white blending slider of grey channel to around '30'.

Duplicate another instance of dove and apply 'Outer glow' layer style. Mask off most of the areas, revealing only around the edge of the dove.

Put the rendered difference clouds on top and set it to 'Color dodge'.

Mask the excessive areas off, resulting in this:




 

Once done, we can group these layers together as 'dove'. An overview of the layers involved:

Cloudy background:


I mixed 2 sets of clouds.

Copy and paste a portion of the clouds to form the background. Mask, rotate, transform, and merge them so that the background is completely filled.

Remove some white off the clouds by dragging the blend slider. We are done with the clouds for now.




 
 

Next step is to flatten the woman and the dove. Duplicate 'woman' and 'dove' groups. Create a new black filled layer and put it below the duplicated groups. Then merge them together

Set this layer to 'Screen' blend mode

Because 'Screen' blend mode knocks out black color, it looks rather fade. At this point, we can bring up the 'woman' group and mask to reveal the areas which are deem faded.
 
 

Using the same reference images of clouds, copy some and place it at the leg

defined a new brush using this shape:

And drew shiny white particles around the body with the new brush

Add in some snow storm effect to dramatize the final picture. As a final step, always sharpen the image a little to increase definition.

Another take at this image, this time with a blue-ish tint.

SOURCE  http://www.123rf.com/blog/blog.php?idblog=b1000167&v=nl&e=0111&id=572360544C6351


















                                                     








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