A Subjective Comparison of 28-70mm zooms: Nikon, Sigma and Tamron

This is an image comparison of photos taken with three different lenses. All photos taken with a Nikon D100, with the exception of the Sony Mavica shot. All exposures were taken with an aperture of f/11. Photos have no sharpening applied and those taken by the D100 were all shot as NEF RAW mode and converted to 72dpi, 8bit JPEGs in PhotoShop7. Auto contrast was applied on each photo segment in PhotoShop.

These results show that the Nikon 28-70 provides the brightest images, the Tamron 28-300 a little darker and the Sigma 24-70 suffering from the most "mudiness." Generally, one might expect a subtle, yet increasing clarity and definition across longer focal lengths given that the same photo segment is being shown at the same size. Overcast skies limit the ideal conditions for making such comparisons.

It's hard to pick out a clear winner, but the brightness of the Nikon set does seem to be best suited for these less-than-ideal conditions.

28 mm	50 mm	70 mm
			Nikon 28-70 f/2.8 AF-S Zoom
			Tamron 28-300 Super Zoom
			Sigma 24-70 Zoom
	Sigma 15-30 Wide Angle Zoom at 28mm
	Sony Mavica FD-85 at widest view.