I have had this lens for roughly 5-6 months now, so I've had plenty of experience with it, considering also this is my primary lens now, replacing my previous Canon 18-55mm IS kit lens.
The Tamron 28-75mm f2.8 mounted on EOS 40D
Lumix DMC-LX3, 1/30s shutter at f/2.0, ISO-80 with 580EXII
The main reasons I opted for this Tamron....
1) The focal length:
The 28-75mm is a very sweet range for general purpose photography and you can practically bring this
lens anywhere and have good confidence that you are going to get the shot, especially when it comes to
frame filling portraits. This lens has an equivalent focal length of 42-112mm on a full frame camera. Not a
really wide lens at 42mm, but I have shot group photos of 20+ people in a tight living room using this lens.
The 28-75mm focal range....great for portraits.
Lumix DMC-LX3, 1/30s shutter at f/2.0, ISO-80 with 580EXII
2) The fixed aperture:
This Tammy comes with a fixed f2.8 aperture throughout the 28-75mm focal length, which means you get
the benefits of a fast f2.8 aperture throughout the zoom range. Very cool and useful for low light and
indoor photography. Compared to the 18-55mm kitlens, the Tammy is roughly 2 stops faster (at 55mm).
The f2.8 also provides better subject isolation given the smaller DOF.
3) The image quality:
One thing you will notice (upgrading from the kitlens) is that the lens quality really shows. Being dubbed
the "SP" suffix in the name means it is Tamron's highest quality lens line. This really shows with vibrantly
colored shots straight out of cam. Sharpness at the center of the frame is also superb. But one thing I
noticed is that shots from this lens tends to be quite warm (yellow).
SP...Tamron's stamp for "superior performance"
Lumix DMC-LX3, 1/30s shutter at f/2.0, ISO-80 with 580EXII
4) Price:
I got my copy for RM1,700 (around May'09). For the price tag, this lens is really great value for money.
The one and only obvious complaint I have for the Tamron is pobably the Autofocus. It tends to hunt quite often indoors and in low light situations. Though with the 580EXII Speedlight mounted, this problem is nearly non-existent (due to the 580EXII's AF assist lamp).
So the bottomline is a great walk-around lens in the Tamron 28-75mm f2.8, the build quality is also very sturdy and the rubbery grips on the lens body gives it much better handling. The macro capabilities of the lens are also quite good, providing 1:2.8 amplification (0.36x magnification). Great lens for beginners and amateurs to start their photography before making the jump to Canon "L" lenses.
The full name:
Tamron SP AF 28-75MM F/2.8 XR Di LD Aspherical (IF)
SP - Super Performance (Tamron's highest quality lens line)
AF - Autofocus
XR - Extra Refractive Glass (reduces lens size)
Di - Digitally Integrated Design (to reduce ghosting, flare, CA and peripheral light fall-off along with improved resolution)
LD - Low-Dispersion lens elements (to reduce chromatic aberration for sharper images)
Aspherical - contains aspherical elements (compensates for spherical aberration and distortion, making for better performance with fewer elements (and thus allowing for smaller, lighter lenses)
(IF) - Internal Focusing
Lens Construction (Groups/Elements) 14/16
Angle of View (on film) 75°-32°
Type of Zooming - Rotation
Diaphragm Blade Number - 7
Minimum Aperture - F/32
Minimum Focus - 0.33m (13") (entire zoom range)
Macro Magnification Ratio - 1:3.9 (at 75mm, on film)
Filter Diameter - 67mm
Weight - 510g (18.0oz.)
Diameter x Length - 73mm x 92mm (2.9in x 3.6in)
Accessory - Lens hood
Available Mounts - Canon, Minolta, Nikon-D, Pentax
Relevant links:
http://www.tamron.com/lenses/prod/2875mm.asp
http://www.the-digital-picture.com/Reviews/Tamron-28-75mm-F-2.8-XR-Di-Lens-Review.aspx
http://www.radugrozescu.com/photo-tech/tamron-28-75-review.html
