Lee,
I have only been using a digital camera since last December and started using Photoshop a little after that. Sharpening seems to be something of a black art - I don't think I've come across two people that offer the same method for sharpening, for example, Martin Evening, in his excellent book "Adobe Photoshop 6 for Photographers" says always use the Unsharp Mask (USM) and suggests starting with settings of 120-200% and radius of 1-2. (You don't say whether you are a Photoshop user, but I shall assume so.) Certainly, you should use the USM rather than the shotgun options for "sharpen" or "sharpen more".
Some people suggest that you should always convert to Lab colour and use USM on the luminance channel to avoid messing the colours.
Michael Reichmann on his superb site at www.luminous-landscape.com
has an excellent discussion of sharpening and resolution at http://www.luminous-landscape.com/sharpness.htm
. One of the previous posters mentioned Ultra-Sharpen, another (commercial) tool is Nik-Sharpener; Michael reviews this at http://www.luminous-landscape.com/nic_sharpner.htm
. Michael also suggests using the high pass filter:
1. On the Layer palette select your Background Layer and right click. Select Duplicate Layer.
2. With this new layer highlighted select Filter / Other / High Pass. Set the Radius to 10 and click OK.
3. Zoom into your image to Actual Pixels level so you can better see what you're going to do next.
4. Go back to the Layer Palette and select Hard Light from the left drop down.
5. Now go to the Opacity Slider and select a level of sharpening that seems best to you. Usually something between 20% and 70% will be best.
(I cut and pasted this directly from the web page at http://www.luminous-landscape.com/high-pass-sharpening.htm
).
I read somewhere that using USM of 500, 0.2, 0 from 1 to 3 times on D30 images works well as they have remarkably little noise at the lower ISO levels.
Fred Miranda - www.fredmiranda.com
- offers several cheap (under 10 bucks) or free Photoshop actions, including EdgeSarpen 16-bit. Fred is a valuable contributor to several forums and says he (most often) applies USM at 300, 0.2, 0 and then uses EdgeSharpen.
Another site http://www.aim-dtp.net/aim/techniques/index.htm
advises the uses of custom blur and sharpen filters (freely downloadable) from the site.
There is a very useful discussion about sharpening and upsizing at http://www.robgalbraith.com …bb=get_topic&f=8&t=000407
.
So what works? Well, they all do. My experience is that a lot will depend on the characteristics of the image. For instance, with an image that has a very blurred background (e.g., with lens settings giving a narrow depth of field) then I often like to select the main subject and just apply sharpening to that; this avoids sharpening the noise in the background. One advantage that us amateurs have is that we can afford the time to play as we don't have deadlines to meet or a living to make from photography
so we can afford the time to play around a little and see what works. I haven't done enough *systematic* experimentation to offer more certain guidelines. If you want somewhere to start, if you are a Photoshop user, then I would try Fred Miranda actions and method first and see what you think. If you don't use Photoshop, experiment with the USM equivalent (assuming there is one) in the package of your choice. Paintshop Pro, for instance, has an almost identical USM capability.
Hope this helps,
Roger