Hoods and filters
Use your lens hood!
The lens hoods provided with most
Carl Zeiss® optics
For many photo enthusiasts, Carl Zeiss lenses have long been the ultimate choice. Many models are available, but the only autofocus Zeiss lenses currently available for use on
Without lens hood (flare, poor contrast) | With lens hood (no flare, high contrast) | ||
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Visible ghosts | Enlarged view No ghosts |
Even though A lenses are uncompromisingly designed with
The scientific approach
It was Ernst Abbe of Carl Zeiss AG who first applied scientific principles to lens design, rather than relying on
of photographic lenses.
Protar® | Planar® | Tessar® | Sonnar® |
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The Carl Zeiss lenses that started it all
Lens hoods block extraneous light
Protar | Planar |
How lens hoods work
Extraneous light
Light needed for image formation
Lens hood
Any light entering the lens that does not come directly from the scene being photographed is extraneous light that needs to be eliminated. Light that grazes the front element at a steep angle or bounces around inside the lens barrel will degrade image quality. A lens hood that is properly designed for the lens on which it is used will effectively block extraneous light that does not contribute directly to the image, ensuring that the lens will deliver the highest resolution and contrast it is capable of. Although most lens hoods for normal to telephoto focal lengths are basic round designs, lens hoods for wide angle lenses often have a “petal” shape that is designed to block unwanted light without intruding into the corners of image area.
Petal hood | Round hood |
Developed by Dr. Paul Rudolph in 1890, this lens was one of the original Anastigmat series. The design was named “Protar” (from the Latin “proto,” or “first”/”origin”) in 1900. The front group was a standard achromatic combination of
effectively suppressing chromatic aberration. This design evolved to become the Unar lens and later the Tessar.
Another Paul Rudolph design, developed in 1897. Initially this design was called the “Anastigmat Series IA.” It features a symmetrical
The Carl Zeiss traditions of innovative technology and uncompromising quality are alive in today’s A series lenses as well.
The unmatched T*
Circular polarizing filters for improved contrast and color
Circular polarizing (PL) filters can be used to eliminate reflections and glare from reflective surfaces such as glass and water, but landscape photographers find them most useful for increasing contrast and saturation in skies, foliage and other icons of the landscape genre. In all cases the filter works by eliminating reflections, but in the latter, it is eliminating reflections from airborne dust and water vapor, thus removing a veil of glare and allowing the true colors of the
The fact that lens coating
Until the introduction of coated lenses, the lens surface would reflect a large percentage of the incoming light, thus reducing transmission and making it difficult to use multiple elements in lens designs. Effective coatings made
it possible to design more complex optics that delivered significantly improved performance. Reduced internal reflection contributed to minimum flare and high contrast.
The Carl Zeiss T* coating is not simply applied to any lens.The T* symbol only appears on
Without circular PL filter | With circular PL filter |
(reduced contrast) | (increased contrast and deep saturation) |
scene to come through.
Carl Zeiss coated lens | Uncoated lens |
Neutral density filters
Sometimes the light is so bright that you’re forced to use smaller apertures or faster shutter speeds than you want to. Neutral density (ND) filters reduce the
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| amount of light entering the lens without affecting the color or tonal balance |
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| in any way, and can be very useful in this type of situation. Suppose you |
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| want to shoot a waterfall using a shutter speed that’s slow enough to blur the |
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| moving water and create a sense of motion, but the lighting at the scene is |
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| too bright. An ND filter will reduce the light intensity so that you can use the |
Without ND filter | With ND filter | relatively slow shutter speed required to achieve the desired effect. |
| (reduced light for slower shutter speed) |
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| Image sensor | Image sensor |
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Reduced reflection | Uncontrolled reflection |
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