I need help with this too.. my pictures come out not sharp enough or too sharp
Yah! Someone else that uses Aperture!
I was beginning to think I was the only one!
So I've done some reading and watched a few tutorials. Here's what I've found.
Aperture's Edge Sharpen tool is the tool to use. It's like Photoshop's unsharpen mask but applies to high contrast edges.
First use the loupe or Z key to zoom in on the image to 100% and look at some high contrast edges.
Set the intensity around 0.9 to 1 to get a nice sharp edge on a high-contrast edge you're looking at... but avoid any artifact or halo... back it off a bit if you see something undesirable.
Then look to some of the other parts of the picture and play with the "Edges" slider. This slider adjusts what's considered an edge vs. not... so as you move it to the right, more things will get sharpened... but you will see noise and other artifacts appear once you slide this too far to the right. Back it off until things that should look smooth are still smooth but hopefully your subtle edges have a bit of added sharpness as well.
It seems it's generally recommended to leave the "Falloff" slider at 0.69 unless you have unavoidable halo effects in which case you can dial it down.
The sweet spot that works for me is usually with Intensity set at 0.9 to 1.0 and Edges set to around 0.3 to 0.4.
Another tool that has a dramatic impact on how sharp the image looks is the "Definition" slider. From what little I know about this, I gather it's somewhat of an edge-based contrast adjustment
. I need to delve into it deeper but I find it can really add the appearance of sharpness (or definition I guess) if adjusted to somewhere around the mid point. Too far to the right and it starts to oversaturate the image and make it look artificial.
Let me know what you find after tweaking some photos.
