Adjusting the Definition (Sharpening) a Photo In Aperture 2.0

[Definition Slider at 100%]

This was a photo I took of my English Mastiff puppy.  The lighting in this situation was terrible, but I made it work.  I set the white balance to 2700 to give the photo a cooler look as the lights gave off a unsightly yellow cast.  If I had more control of the scene I would have added extra lighting and used a flash.  This would have added much needed illumination to the scene and allowed me to set a faster shutter, and step down to a smoother, lower ISO.  Given the conditions I think the picture turned out pretty good.

In Aperture 2.0 I moved the definition slider to 100% which sharpened the picture, but added slight halation around some areas of Zeus's head and the edge of the black blanket, although it is negligible.  Flash would have solved all of these problems, and there would have been no need to sharpen the photo as it would have brought out more texture within the photo.  The Mark II's photo's are remarkable sharp as is, and can be further tweaked by using the camera's custom presets.  However, the Mark II is ideal for portrait photography and give a softer, gentler feel and sharpening wouldn't be advised.  This is the camera of choice for many professional portrait/wedding photographers, as well as serious photo enthusiasts in general.

"Zeus"
Male English Mastiff
Nine weeks old

Canon 5D Mark II
Focal Length 45
Aperture 4
Shutter 1/25
ISO 1600

This is the same photo in black and white without any sharpening via the Aperture 2.0 definition slider/toggle.  Sometimes black and white photography that has been sharpened through this feature will be more noticeable. There is a slight halation on the edges of objects such as Zeus's head and the black blanked the background.  Generally speaking, the more contrasted an object is the more this will be noticed.

[Definition Slider at 100%]

[No Adjustment in Definition]

Below are the same three photographs.  They are cropped for a closer look at Zeus's head and the effects of using the definition slider at 100%.

[Cropped at 100% Definition]

[Cropped at 100% Definition]

[No Adjustment in Definition]

So as you can see there is very little quality lost when making adjustments in Aperture 2.0 with the definition slider.  As expected, there would be even less if you made an adjustment by increasing the definition by 50 points or by 25 points.  Even at roughly a 300% crop the Canon 5D Mark II shoots razor sharp images.  The main difference that can be seen is a smoother texture in Zeus's fur in the untouched photo.  This is personal preference.

There are seven levels of sharpness that can be shot with the Canon 5D Mark II.  This photo was shot at level 5.  For even crisper images you can go all the way up to level 7.  There is very slight halation at these levels, and you likely won't notice it unless you are looking at an image that is highly magnified. 

In shooting close ups of my dog I prefer to adjust the definition post production, however if I was shooting a person I would likely leave the camera to it's own devices and let it do what it does best - shoot incredible portraits by creating a smooth even surface on the subjects face.  Changing the definition will bring out wrinkles in your subject.