Sigma 70-300 "Wild Lily" Macro Test
1/1500s f/5.6 at 300.0mm iso200
The lens is wide open..f/5.6 is as fast as it gets at 300mm. This image is noticeable less focused and contrasty than at f/8.0. There is also noticeable light falloff...the picture is darker than f8.0.
1/750s f/8.0 at 300.0mm iso200
Better than f5.6 but still not sharp and contrasty. Just wait.
1/500s f/9.5 at 300.0mm iso200
Highest recommended apature for handheld macros.
Not as good as at f13, but at a ss of 1/500 high enough to be the maximum apature recommended for handheld.
1/350s f/11.0 @300mm iso200
A surprise. Not really better than f10
The one advantage is that the apature has finally gotten small enough to provide adquate depth of field even for the rear of the flower. This is a function of the 300mm length, and can't be avoided...with this length macro a higher apature is mandated to gain adequate depth of field.
1/350s f/13.0 at 300.0mm iso200
This is the "optimal" image taken by my Nikon D50/Sigma 70-300 APO combination in a test I did to find out at what aperture the macro worked best.
1/250s f/16.0 at 300.0mm iso200
Another surprise. This represents a step backward from f13. Why? Could be defraction, but then f/19 should be worse still....it isn't. Your guess is as good as mine.
1/180s f/19.0 at 300.0mm iso200
Second best macro setting. This is second to f13 for sharpness and contrast in shooting flowers. However, way too much background.
1/125s f/22.0 at 300.0mm iso200
Noticeable loss of sharpness, not unexpected. It's all downhill from here.
1/90s f/27.0 at 300.0mm iso200
Perhaps still good enough for scenic shots...but of no use for macros.
1/45s f/32.0 at 300.0mm iso200
Worst of all except for f5.6.
Even for scenic shots I would use f22, not the smaller apatures.
click on thumbnails for full image