Review - Sigma 18-50mm F2.8 EX DC

[ortega]

Sigma 18-50mm F2.8 EX DC

for those who want to know, I did some tests shots and post them here
make your own conclusions about the quality

All images taken using a Nikon D80, ISO 100, Aperture priority

Resized full frame @ f8 and f2.8 (tripod mounted)
note the vignetting on the f2.8 image

now at 50mm uncropped images

 

[ortega]

Next some 100% cropped images

100% Crop - Center from the 18mm shot

 

[ortega]

100% Crop top right hand Corner from the 18mm shot

 

[ortega]

Next, CA tests at different aperture settings

All images taken with the same exposure using manual mode

 

[ortega]

Magnification - manual focus set to minimum
for greatest magnification at maxumum focal lenght

image resized to 700px wide

Bokeh

set to get minimum dof and maximum oof of background
image resized to 700px wide

 

[ortega]

I have also at the same time done the same test for the

Tamron SP AF17-50mm F/2.8 XR Di II LD Aspherical [IF]

and the

Nikon AF-S DX 18-70mm f/3.5-4.5G

 

[vincecarlo]

the pix look a little soft @f2.8. does it improve by f4.0?