Fotodex.ro

Vignetare

RO: Vignetare | EN: Vignetting | DE: Vignettierung | FR: Vignettage

  1. Efect produs de scăderea luminozității proiecției unui obiectiv către marginile imaginii.
  2. Efect produs de scăderea luminozității către marginile imaginii produs de accesorii, mecanisme sau alte obiecte care împedică formarea proiecției la mărimea necesară pentru materialul fotosensibil folosit. [ Este denumită vignetare mecanică în mod eronat, ea fiind tot un efect optic, nu mecanic, de umbrire]
  3. Efect de înnegrire a colțurilor imaginii, realizat în postprocesare.
vignetting

(1) When unintentional, it is underexposure at the image’s edges or corners caused by an unsuitable lens hood, filter or other attachment that partially blocks the field of view. (2) When intentional, it is an image printing technique where the central area is fully printed but its edges gradually fade. Vignetting can also be achieved when taking the picture by placing a vignette mask in front of the lens.

Photo Tips
vignetare

Defect al sistemului optic ce consta din obturarea razelor laterale ce intra in obiectiv si care se traduce prin întunecarea colturilor pe copia pozitiva; apare mai ales prin amplasarea de filtre cu diametru insuficient.

F64.ro
vignetare

Incompatibilitate intre un obiectiv si un accesoriu (filtru, parasolar) ce se traduce prin umbrirea severa a colturilor cadrului.

Foto Magazine
vignetare

Defect in proiectarea formulelor obiectivelor ce se traduc prin scaderea intensitatii luminoase la colturile imaginii. Valori de 0,5 IE sunt considerate acceptabile si practic nu se observa.

Foto Magazine
vignetting

The term that describes the darkening of the outer edges of the image area due to the use of a filter or add-on lens. Most noticeable when the zoom lens is in full wide-angle. It is also sometimes used as a special effect in the photo editing stage of development.

allthingsphotography
vignetting

fall-off in brightness at the edges of an image, slide, or print. Can be caused by poor lens design, using a lens hood not matched to the lens, or attaching too many filters to the front of the lens.

kodakglosarry1999
vignetting

Darkening of the edges of a photographic image due to the inability of a lens to evenly distribute light to the corners of the frame. While correctable with filtration using on-camera, center-weighted neutral density filters, or electronically in Photoshop, vignetting is often valuable as a creative device to direct the eye back to the center of the frame.

bhphotovideo
vignetting

Light rays entering the lens from the edges of the picture area are partially blocked by the lens frames in front of and behind the diaphragm, preventing all the rays from passing through the effective aperture (diaphragm diameter) and causing light fall-off in the peripheral areas of the image. This type of vignetting can be eliminated by stopping down the lens.

canonglossaryeu
vignetting

Reduced brightness or saturation at edges of image, compared to image s center.

Canon glossary
vignetting

Underexposure of image corners produced deliberately by shadingor unintentionally by inappropriate equipment, such as unsuitable lens hood or badlydesigned lens. A common fault of wide-angle lenses, owing to reflection cut-off,etc. of some of the very oblique rays. May be caused in some long-focus lenses bythe length of the lens barrel.

mirglossary
vignetting

Vignetting (or light shading) is a progressive attenuation of brightness of an image when going far from its center, meaning that the corners of a rectangular image tend to be dark. Read more about how vignetting is defined, measured and scored.

dxoglossary
vignetting

Slight light falloff in the lens causes vignetting. Due to the physical properties of light passing through lenses it is impossible to get the same amount of light to the edges of the circle as the center (the light going to the edges has to travel further, thus falls off more).This light fall off creates a very slight reduction of exposure on the corners of an image. This darkening in the corners is called vignetting.Because light falls off (decreases) with the square of the distance it travels, light that travels farthest (from the lens to the edge of the circle versus from the lens to the center of the frame) will always be slightly reduced. All lenses exhibit some light fall off towards the edges but wide angle lenses as well as some telephoto zoom lenses are most prone due to their optical design. Further, a lens will generally show the most vignetting at it s widest aperture.With smaller format cameras (such as DX format D-SLRs) the light fall off is less noticeable because only the center of the circle of illumination is used. With larger format cameras (like 35mm film or FX format cameras) more of the circle is used and there will be more difference between the center of the frame and the edges.A second type of vignetting is called Mechanical Vignetting. This is simply vignetting caused by something blocking the light path such as a filter with too thick a mount or stacking several filters together. Also, using the wrong lens hood on a lens can cause mechanical vignetting.In most shooting conditions (proper exposure, normal subjects, etc.) light falloff will be minimal. However, at some f/stops, focal lengths and with some lenses it is normal to have more light falloff. If you have vignetting with a particular shot, change the lens focal length or aperture (lenses shot wide open will have the most vignetting, so stopping down a stop or two can help) until the vignetting is minimized. While vignetting may be easy to see and reproduce in a test situation, in real world shooting it is generally invisible.For those conditions where vignetting is obvious in a photo, Nikon View NX software will automatically compensate for vignetting and Capture NX2 software includes a Vignette Control slider to further reduce the visible effect without noticeably changing the overall image.

nikongrossary