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Post by Snappersforum on Aug 30, 2013 15:33:04 GMT
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Post by Snappersforum on Aug 30, 2013 15:35:01 GMT
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Post by Snappersforum on Aug 30, 2013 15:42:20 GMT
make your own
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Post by Snappersforum on Aug 31, 2013 6:44:59 GMT
A camera lens hood is used by photographers to make sharper images in conditions where light hits the lens element from the side. Lens hoods come in a variety of shapes and sizes, and choosing one can prove to be a chore. This is especially true for those who have never used a lens hood and can’t identify the differences between each type. Before purchasing a lens hood, photographers should understand the purpose of a lens hood and then identify the advantages and limitations of each type of hood. The photographer will have to identify their own needs and select the type, shape, and size of lens hood[/url] that works for them. Reducing Flare and Glare With a Lens HoodA camera lens hood is a device that attaches to the end of a camera lens. Its purpose is to prevent flare which can significantly affect the quality of the image that is being captured. Flare occurs when light hits the sides of the lens element. This can cause a glare or a ghost image from the side of the picture. Additionally, when light hits the element from the side, the resulting picture will not be as sharp as when that light was blocked out.BenefitsAside from the obvious benefits of reducing flare and glare, a lens hood also helps to protect the lens itself. Many photographers use a lens cap as a way to protect the lens when the camera is not in use, but these can be hard to keep up with and take time to remove and put back on. The lens hood provides a barrier around the lens element so that it is protected from damage, moisture, and dirt. This allows the photographer to move around and take pictures freely without having to remove a lens cap.DrawbacksOne of the disadvantages to a lens hood is "vignetting." This occurs when the lens hood is too large for the lens. Vignetting is an effect on a photograph where the edges of the photo gradually fade out. Vignetting occurs with a lens hood because the angle of view is blocked by the lens hood and the entire image cannot be effectively captured.Another limitation is that can be expensive. Aside from the initial investment, lens hoods may need to be replaced often. Since the lens hood sticks out farther than the lens, it is more likely to be bumped and broken. Fortunately, the cost of replacing a lens hood is much cheaper than the cost of replacing the lens assembly itself. Lens Hood TypesMost shoppers and photographers will be looking for a standard lens hood, which is why this is the most common type. Photographers will also be able to find lens hoods for wide-angle and telephoto lenses. Determining the type of lens hood needed depends on the camera. If a photographer has never used a lens hood before, then it might be a good idea to test a few out to see which one works the best. Lens hoods come in all shapes and sizes, and they are made from a variety of materials. Additionally, lens hoods can be mounted to the camera in different ways. The four mounting mechanisms used for lens hoods are listed in the table below.Mounting Mechanism Description [/url][/b][/center] Screw-in or screw-on lens hoods attach to the front of the lens using the threads that are present. These are the most common types of lens hoods available.[/url][/b][/center] As the name suggests, a slip-on lens hood slides over the lens and can be tightened down over the end to secure it in place.[/url][/b][/center] Snap-on lens hoods use a spring-type retainer ring to lock onto the front of the lens.[/url][/b][/center] A bayonet lens hood mounts onto the end of a lens with a twist.When it comes to choosing the appropriate type, it all comes down to convenience and personal preference. As seen in the table above, screw-on and bayonet lens hoods seem to be similar. The difference between the two is that screw-on lens hoods are universal whereas bayonet lens hoods will only work with lenses that have compatible mounts. It is unlikely that the bayonet lens hood will fit on a mount for a different type of hood.Lens Hood ShapesLens hoods come in several different shapes and each one blocks the light in a different way. Some are more effective than others, and choosing the best one comes down to personal preference and the lighting conditions. The different shapes for lens hoods are listed and described in the table below.Shape Description [/url][/b][/center] The round hood mimics the shape of the lens, but extends a few inches beyond the end of the lens. It is also known as a circular lens hood.[/url][/b][/center] The tulip hood has longer pieces along the top and bottom to cover the gaps that are left by the round hood. It is also known as a petal lens hood[/url]. Rectangular A rectangular hood is a box-shaped attachment that connects to the end of the lens. It matches the shape of the light coming into the lens to be effective in blocking light coming from the sides.Chopped Tulip Since the extended pieces of the tulip shaped lens hood can be cumbersome to carry, these are shortened to make the chopped tulip hood.7.5+9.5 Shortening the ends of the tulip hood leaves gaps that can allow light to enter. These two gaps on the top and bottom are filled with short caps.The shape of a lens hood will determine how effectively it blocks light from the lens element. The round hood is the least effective in blocking light because it does not have the same as the light that enters the lens. The light that touches the lens has a pyramidal cone shape, and the circular shape of a round hood would block some of the light but still leave some gaps.Lens Hood MaterialsLens hoods are typically made of metal[/url], plastic, or rubber materials. Each of the materials has its benefits and disadvantages. For example, metal lens hoods are known for providing better protection to the lens because they are sturdier. Rubber and plastic lens hoods are often collapsible, which means that they can fold down to take up less space. Because rubber and plastic are both flexible, they aren’t able to offer the same amount of protection that metal lens hoods do. Lens Hood SizesThe size of a lens hood is extremely important because if they are too small or too large then they won’t work as intended. If the lens hood is too short then the light will not be blocked entirely, and flare can still occur. If the lens hood is too large, then vignetting will occur and the edges of the photograph will be obscured.Choosing the Proper Size Lens HoodWhen possible, photographers should test out different size lens hoods to see which one is the best fit for their lenses. They can test the hood by attaching it to the camera and snapping a few pictures in situations where bright light appears in the corners. When using a DSLR camera, it is easy to test because the image results will appear on the rear LCD screen. To test for vignetting, photographers should take a photograph with bright lights near the corners and look for any shadows or obstruction to appear.Making a Lens Hood Using Step Up RingsIn some instances where a standard size lens hood will not fit on the lens of a camera. This usually occurs with on-camera lenses. These lenses measure 28 mm which is smaller than the standard size lens hood. Photographers can use step up rings[/u] to construct their own makeshift lens hoods for any size lens. A step up ring is an adapter ring that is placed on the end of the lens so that larger filters can be attached. Using different sized step up rings, photographers can add several to the end of the camera to make a circular lens hood. How to Store a Lens HoodDepending on the size of the lens hood, finding a place to store it when not in use can be a problem. They are known to take up a lot of space in a camera bag when stored alone. Rather than removing the lens hood to set aside for later use, photographers can simply reverse the lens hood over the lens. This keeps it out of the way and won’t take up additional space in the camera bag. This also keeps the lens hood handy for when it does need to be used again._________________________ Composed/Posted with WYSIWYG BBCode Editor
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