Tamron Zoom Lens AF 28-300 mm f/3.5-6.3 XR Di LD Aspherical (IF) Macro
|Aperture Range [f]||3.5-6.3 to 22-40||Closest Focus||0.49m / 1.6 ft.|
|Dimensions||126mm x 74mm / 4.9 in. x 2,9 in.||Magnification Ratio||0.33x / 1:3|
|Weight||550g / 19.4 oz||Filter Size||67mm|
This is a very compact and and high power (10.7x) zoom lens that fits on full frame, 24x36mm, cameras. Due to it's zoom power is very versatile and attractive, especially when in travel. It focuses well, but slow, so it is generally not recommended for sports/action events, especially in low light.
Click on the "Various f-stops" thumbnail below, to see the charts made at different f stops and focal lengths. Only one circle chart is displayed: at the 12th mm from the center image (The center chart was always sharp, so that there were no significant differences). The sharpness was best mostly at f/11, but at wide angle settings the f/8 gave also good results.
I've tested this Tamron lens on 8 focal lenghts, 28, 35, 50, 75, 110, 150, 220, and 300 mm. To see the charts in full magnification please click on the thumbnails below (note: large images, 1720x1850, 0.5M each). Dependence of the image quality in various parts of the full 24x36mm frame is shown, with the average resolution in hundreds of line widths per picture height (LW/PH), given below each chart.
Tests at low fs
Tests at f/8.0
Tests at f/11
At wide open apertures the lens sharpness is relatively poor, with a relatively low contrast. The worst problem with sharpness is that it is uneven in different line directions, that badly distorts images (see for the ranges of numbers under a single chart). I do not recommend using it at full apertures because of that.
At f/11 the performance is acceptable for DSLR's with APS-C sensors. Users of cameras with below 8M pixel sensors would not see any sharpness issues, perhaps a little softness at over 150mm focal lengths, but nothing to worry about. The sharpness right in the center is very good at all focal settings, but falls of with the increasing distance from the center, at high focal lengths.
Distortions are the highest in the middle of focal lengths. At 110mm there is about 4.5% increase of the circle diameter at the sides of the frame compared to the circle size at the center. At the sides the circles are elongated, with a 6% difference in extreme diameters. Chromatic aberration problems are opposite: high at extreme focal lenghts and low in the middle.
Compared to the Canon's 28-300mm 'Luxury' lens, its performance is similar at medium focal lengths, better at the corners, and worse at wide angle- and tele- settings. I don't recommend it using for high pixel or film full frame cameras. However, it is an acceptable choice for APS-C sensor type cameras (those that are compatible with EF-S lenses), and because of the size, weight and price it's a better choice than the Canon lens, especially for travel.
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