26.10.2011., srijeda


Filter Paper Manufacturers. Hoya 72mm Circularizing Polarizing Filter. Simple High Pass Filter.

Filter Paper Manufacturers

filter paper manufacturers

    paper manufacturers
  • (paper manufacture) (in  paper pulp; in  papermaking: Chemical wood pulp )

  • A screen, plate, or layer of a substance that absorbs light or other radiation or selectively absorbs some of its components

  • device that removes something from whatever passes through it

  • A device for suppressing electrical or sound waves of frequencies not required

  • remove by passing through a filter; "filter out the impurities"

  • A porous device for removing impurities or solid particles from a liquid or gas passed through it

  • an electrical device that alters the frequency spectrum of signals passing through it

filter paper manufacturers - Panasonic-2 Year

Panasonic-2 Year Accidental Damage Coverage for Cameras/Camcorders 350 - 499.99

Panasonic-2 Year Accidental Damage Coverage for Cameras/Camcorders 350 - 499.99

DON'T buy a Service Contract on your digital camera unless you get Accidental Damage Coverage! That's what we offer you! We make a good camera; and you will try your best to take care of it! But accidents do happen! Unless you buy accidental damage coverage; it's not covered! On a digital camera, don't let someone's low price for an extended service contract distract you from what it really covers and what you really need to be covered! We are the manufacturer, and we know accidental coverage makes good CENTS!

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color of the wind

color of the wind

Picture: just Bokeh
Location: Water Park, Olympic Stadium, Beijing.

In photography, bokeh (Originally /?bo?k?/,[1] /?bo?ke?/ boh-kay, and also sometimes heard as /?bo?k?/ boh-k?,[2] Japanese: [boke]) is the blur,[3][4] or the aesthetic quality of the blur,[5][6][7] in out-of-focus areas of an image, or "the way the lens renders out-of-focus points of light."[8] Differences in lens aberrations and aperture shape cause some lens designs to blur the image in a way that is pleasing to the eye, while others produce blurring that is unpleasant or distracting—"good" and "bad" bokeh, respectively.[3] Bokeh occurs for parts of the scene that lie outside the depth of field. Photographers sometimes deliberately use a shallow focus technique to create images with prominent out-of-focus regions.
Bokeh is often most visible around small background highlights, such as specular reflections and light sources, which is why it is often associated with such areas.[3] However, bokeh is not limited to highlights; blur occurs in all out-of-focus regions of the image.


The term comes from the Japanese word boke (?? or ??), which means "blur" or "haze", or boke-aji (???), the "blur quality". The Japanese term boke is also used in the sense of a mental haze or senility.[9] The term bokashi (???) is related, meaning intentional blurring or gradation.
The English spelling bokeh was popularized in 1997 in Photo Techniques magazine, when Mike Johnston, the editor at the time, commissioned three papers on the topic for the March/April 1997 issue; he altered the spelling to sest the correct pronunciation to English speakers, saying "it is properly pronounced with bo as in bone and ke as in Kenneth, with equal stress on either syllable".[4] The spellings bokeh and boke have both been in use at least since 1996, when Merklinger had sested "or Bokeh if you prefer."[10] The term bokeh has appeared in photography books at least since 1998.[5] It is sometimes pronounced /?bo?k?/ (boke-uh).[2]


Although difficult to quantify, some lenses enhance overall image quality by producing more subjectively pleasing out-of-focus areas. Good bokeh is especially important for large-aperture lenses, macro lenses, and long telephoto lenses because they are typically used with a shallow depth of field. Bokeh is also important for medium telephoto "portrait lenses" (typically 85–150 mm on 35 mm format) because in portraiture photography, the photographer typically seeks to obtain a shallow depth of field to achieve an out-of-focus background and make the subject stand out.
Bokeh characteristics may be quantified by examining the image's circle of confusion. In out-of-focus areas, each point of light becomes an image of the aperture, generally a more or less round disc. Depending how a lens is corrected for spherical aberration, the disc may be uniformly illuminated, brighter near the edge, or brighter near the center. Lenses that are poorly corrected for spherical aberration will show one kind of disc for out-of-focus points in front of the plane of focus, and a different kind for points behind. This may actually be desirable, as blur circles that are dimmer near the edges produce less-defined shapes which blend smoothly with the surrounding image. Lens manufacturers including Nikon, Minolta, and Sony make lenses designed with specific controls to change the rendering of the out-of-focus areas. The shape of the aperture has an influence on the subjective quality of bokeh as well. For conventional lens designs (with bladed apertures), when a lens is stopped down smaller than its maximum aperture size (minimum f-number), out-of-focus points are blurred into the polygonal shape formed by the aperture blades. This is most apparent when a lens produces hard-edged bokeh. For this reason, some lenses have many aperture blades and/or blades with curved edges to make the aperture more closely approximate a circle rather than a polygon. Minolta has been on the forefront of promoting and introducing lenses with near-ideal circular apertures since 1987, but, since bokeh has become a recognized property of lenses, most other manufacturers now offer lenses with shape-optimized diaphragms, at least for the domain of portraiture photography. In contrast, a catadioptric telephoto lens renders bokehs resembling doughnuts, because its secondary mirror blocks the central part of the aperture opening. Recently, photographers have exploited the shape of the bokeh by creating a simple mask out of card with shapes such as hearts or stars, that the photographer wishes the bokeh to be, and placing it over the lens.[11]
Leica lenses, especially vintage ones, are often claimed to excel in bokeh quality[citation needed], although Leica photographers have tended to make more use of maximum aperture due to the lenses' ability to maintain good sharpness at wide openin

Lens Adaptor Tube Prototype #1

Lens Adaptor Tube Prototype #1

This is a lens adaptor tube I've recently designed and built. Its purpose is to allow filters, hoods and add-on lenses to be mounted on certain camera models that don't have threads or adaptors provided for them, by the manufacturers. The three models are the Canon SX1 and SX10 and the Sony HX1. The Canon cameras have a bayonet mount for hoods, but it doesn't allow filters or lenses to be attached. Lensmate sells an adaptor for filters and lens caps that fits the SX1 and SX10, but it can't be used for add-on telextenders that would put strain on the camera's extending lens. Raynox makes a macro lens and an adaptor that fits these cameras, by clipping into the inside of the lens barrel.

The Sony HX1 camera has mounting threads at its lens base for a telextender Sony sells, that has a built-in extended tube at its inside end. This telextender doesn't need an adaptor tube, but other add-on lenses that Sony sold for earlier models, need an adaptor to fit on the HX1. The adaptor for previous models is not long enough to work on its larger lens, unless an extension ring could be found of the right size for it. I don't know if the earlier adaptor, that fit the H-50 camera and other models, has any difference in the contours at its base, that would prevent it from being mounted on the HX1, if an extension ring were used on it. The Pemaraal Co. may make an adaptor tube for the HX1 later, but this is not certain at this time.

This adaptor was built from two ABS plastic tubes of different diameters, that were fused, one inside the other, with urethane glue (Gorilla or Ultimate Glue).. A 67mm to 58mm step-down ring is mounted in the end, with J-B Weld epoxy putty. The adaptor slides over the outer base of the camera's lens. There are three stretched wraps of thick, self-bonding rubber tape, stretched around the base. This provides a firm, but cushioned attachment. This is the type of tape often used by electricians for outdoor or waterproof connections and has a paper layer between the wraps on the roll. There are cut-outs in the base of the tube, to provide clearance for control buttons and knobs and for the microphone openings.

The adaptor must have the outer ring mounted so that there's about 2mm of clearance
between it and the fully extended lens. The lens comes out when the camera is turned on, but doesn't extend all the way, except at full zoom.

It's important that all the parts are shaped and assembled straight in line. One way to check for alignment, is to mount a telextender on the adaptor and back off on the zoom, until vignetting occurs. Then, you can see how well-centered the image circle is in the frame.

The camera shown here, is a Canon S5 IS. This model doesn't need this type of adaptor, as there are commercially-available adaptors that have a bayonet-mount that attaches to the lens base. But, I bult this one for the S5, to demonstrate how it could be done for the models that need it. The base rings on some models are not solidly attached, but just stuck on with some small pieces of double-sided tape. On the S5, this ring has "Image Stabilized" and "12X" decals on it. I had to pull it off the S5 and re-fit it with some shoe-goo (also known as "goop"), for a solid, but removable (I hope) attachment. The dimensions of this adaptor for the S5 are: 67mm in length, 61mm in inside diameter at the base, which is 2mm larger than the lens base and 69mm in inside diameter at the outer end, which flares out where the ring is positioned. The wall thickness of the adaptor is 4mm. There's three more pictures of it, that follow this one.

Steve McDonald

filter paper manufacturers

See also:

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cascade 1000 canister filter reviews

talon oil filter housing

fir filter design using vhdl

solar powered pond pumps and filters

christian net internet filter

catalog baldwin filter

planted aquarium filter

filter coffee machines commercial

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72mm infrared filter, pentek bag filters, matrikx water filter cartridge, fairey arlon hydraulic filters, filter design tool