Here is a brief presentation of some useful Photoshop techniques to sharpen blurry photographs.
The basis for this technique is to start with an image that is much larger than needed, where downsampling will interpolate several blurry pixels into a single pixel that better captures original details.
For example, let's look at my original image: a dark, blurry photo about 1800 pixels square, reduced here. Since I need an image that is only 400 pixels square, I'll now scale down the image to final size, thereby sampling out some blurry pixels and noise:
From the menu, I select "image size" and type in my final resolution of 400 pixels.
At first glance, the downsampled image won't look different. However, the small pic is cleaner, and will respond better to subsequent contrast and sharpening techniques. Since image clarity is improved by good tonal range, we'll first set the white point using Levels.
Select Levels (control L) and simply move the white input slider to the upper range of the image detail, as shown by the arrow:
Without any sharpening, detail clarity is improved by increasing the tonal range.
Clarity is improved further by opening the curves dialog, and modifying the tonal curves.
Here, a subtle tonal curve applied to highlights and shadows will help better define the coin's features.
Since this method increases contrast, it requires further color balance and desaturation--which also improves image clarity. The result is already a big improvement over the original:
Now it's time to sharpen those details enhanced already by downsampling and contrast adjustment. Open the "smart sharpen" dialog and begin experimenting with different sharpening methods and values. This is a trial and error process which you'll fine-tune over time. If the situation calls for it, I will sharpen the photo twice using different values.
Now it's time to compare the results: the original photo to the final image. The final result is a bit grainy, but an overall better presentation of the coin:
Posted 12/15/2009 6:18 pm
