On Day 1 I focused on the build and ergonomics of the lens and it’s general performance with my D90 By 135mm, there has been a slight drop in resolution, with the lens still producing good centre sharpness wide open. The best quality images are still produced between f/8 and f/11 with the sharpness across the frame being absolutely uniform at f/11. On day 2 it was a Dog Day of summer and I was on a Photo walk in New York with the Sigma 70-300 f/4-5.6 DG Macro When it comes to colours it gives a very surreal but natural look, probably the best explanation of its colours are "ultra realism" its not flat but not deep either, its got the nice digital look that we look for in Plasma displays.

This is the least expensive of the Sigma 70-300mm autofocus zoom lenses. It has a macro mode offering 0.5x magnification. Its range is useful for portraiture, amateur sports, and trips to the zoo. Venture further into the zoom range and the clarity drops off noticeably. The lens is still capable of producing acceptable results for most wide open, but stopping down a couple of stops will improve the clarity of images. In use, I did notice a drop in contrast at 300mm, which will affect the apparent sharpness of images. Used in Macro mode, this lens shines as this shot of a Southern Hawker Dragonfly in flight shows. Taken on a Canon 1D with the lens set to manual focus. 1/800sec at f/8 and ISO500 When it comes to zooming the only time it suffers is all the way zoomed out and all the way zoomed in but everything in-between its 10/10. When i say everything in-between, i mean 71mm-299mm, but on the longer end i have found it focus goes weird after 296mmI have used this lens quite a bit on my K5 and I like it. I use it in situation where I need different focal for fast subjects. For example, it is very convenient in amusement parks and animal shows. The AF is very fast and pictures are ok. So, I am very satisfied with the results. Contrast is good, as is colour rendition,sharpness and resolution. Maybe a tad soft wide open, but it is more than useable. this lens is much more better corrected than the Sigma 3.5-4.5/70-210 APO MACRO with unfortunately some visible CAs

As a zoom lens, the Sigma 70-300 f/4-5.6 DG Macro is a great. When you let the sunshine in, you steady yourself, then pull the trigger, you can get amazing shots. At 300 mm wide open (f 5.6), the Tair (f 4.5) captures more detail. The Revuenon (Tele-Ennalyt) (f 5.6) gets less. The Sigma 70-300 colours look nicer to my eye; more natural. The Sigma 75-300 APO gets less detail also, but its colours are nicer still (though possibly less natural). The Sigma 75-300 non-APO λ-2 also gets less detail; its colours more resemble the 70-300. With the 70-300, CA is apparent in high contrast OOF areas, this is the only time I notice CA.My copy is decent sharp at all focal lengths. I got excellent results, very sharp at 70 mm, not as sharp as my FA77 but enough. It is weaker beyond 200 mm, but it can still give acceptable results even at 300mm in good light.

At 70mm this lens produces images of good resolution from the widest aperture right down to f/16, with the edges gradually improving as the lens is stopped down. The best quality images at 70mm are produced between f/8 and f/11.Below is our lens test data. To find out how to use these graphs look at this article: How we test lenses Overall. the Sigma 70-300mm OS is a good value alternative to the camera manufacturer's own offerings, providing decent enough resolution at a lower price point than independent equivalents with low distortion and decent enough resistance to flare and ghosting.