Fraktklass A
29 kr
Aldrig har det varit enklare att fånga suveräna rörliga motiv. Detta objektiv kan användas med både digital SLR och 35mm kamera.
Objektivet har en närgräns på 0,95m, en av de bästa närgränser som finns på teleobjektiv. Brännvidden 70-300motsvarar 109-465mm i 35mm.
Den nya fattningen till Nikon D40/D40x väger 458 gram, en ny mekanisk konstruktion har gjort det möjligt att utrusta objektivet med en extremt snabb zoommotor utan att behöva göra avkall på kraven på låg vikt och kompakt utförande. Objektivets ergonomi har förbättrats med ett gummigrepp på fokus- och zoomringarna och ett zoomlås förhindrar att objektivet glider ut när kameran bärs hängande över axeln.
Vänligen notera: 70-300mm objektivet finns tillgängligt med en inbyggd motor för Nikon D40, D40X och D60 (Model A17NII) sedan ungefär februari 2008. A17N modellen som fanns tillgänglig fram till februari 2008 är endast kompatibel med D40/D40X/D60 i MF läget eftersom det inte har en inbyggd motor.
The MTF charts of the 70-300mm USD VC
How to Read MTF Charts?
A MTF (Modulation Transfer Function) curve describes to which extent the tested lens can reproduce the lifelike contrast of a subject in the images that it captures.
The X axis shows the distance from the center of the image toward the edges and the y axis shows the contrast from 0 to 1 (0-100%).
The thicker lines represent the contrast of 10 lines per mm and the thinner lines 30 lines per mm.
The closer the 10 lp/mm (line pairs per millimeter) curve (the thick line for low frequency) in an MTF chart to “1” of the vertical axis, the higher the contrast reproduction performance of the tested lens will be. A value of 1 would mean that the lens completely reproduces the contrast of 10lp/mm at that point in the image, meaning that the contrast is very good.
The closer the 30 lp/mm curve (the thin line for high frequency) is to “1”, the higher the resolving power of the lens. Here the lines are closer together. A value of “1” would mean that the 30 lp/mm lines are reproduced completely separate, and that the resolution and sharpness of the lens is very good.
In addition, contrast changes depending on the direction. This is demonstrated by the differently colored lines. The yellow line represents the sagittal (radial) direction and the blue line indicates the performance in the meridional (circumferential) direction.
A high-quality lens delivers good optical performance over the entire image field. The contrast only begins to fall off at the edges of the image. The MTF of the 70-300mm USD shows a good balance, ensuring sharp images that are high in contrast.
Performance characteristics of photographic lenses cannot be solely expressed with the use of MTF charts. There are several other factors that are to be taken into account such as the compensation of various aberrations as well as personal preferences in terms of softness.
This lens' advanced optical design employs a sophisticated XLD (Extra Low Dispersion) lens element made from specialized high-grade glass that has lower dispersive properties than standard LD lenses (where refraction causes the dispersion of white light into spectral hues).
The dispersive properties of the XLD lens are at a level similar to fluorite, and in combination with LD elements make for an optimal optical design that delivers best in class resolution with advanced axial chromatic and magnification aberration correction - major inhibitors of image quality enhancement. The result is a lens that delivers sharp contrast and better descriptive performance throughout the entire zoom range.
ngThe lens is equipped with Tamron’s first-ever ultrasonic auto-focus drive USD (Ultrasonic Silent Drive). It achieves faster focusing making this telephoto lens perfect for photography of sports, motor racing and other fast-moving subjects. With advanced motor technology and newly developed software, Tamron's USD delivers precise and silent focusing at turbo speed.
| Kategori: | Objektiv |
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| Tillverkare: | Tamron |
| Releasedatum: | 2012-01-01 |
| Leveranstid: | 1-3 arbetsdagar |
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