User Guide

ACDSee Pro 2.5 - User Guide
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Horizontal
position
Specifies the blur's center point on the horizontal axis.
Vertical position Specifies the blur's center point on the vertical axis.
Adding and removing image noise
About noise and noise reduction
Image noise looks like random black, white, or colored pixels in an area of a photo where there
should be solid color, such as a dark night sky. In digital photography, noise is typically more
visible in the dark areas of a photo.
There are many causes of image noise. You will increase image noise if you use a high ISO
setting (such as ISO 400) to capture a photo, or if you extend the exposure time. (You would
typically use a high ISO setting and extend exposure time to take a photo in low light.)
However, image noise can be caused by dead or stuck pixels in a digital camera's image
sensor. Similarly, dust on a camera lens or scanner bed can cause noise by blocking or
reflecting light.
Noise is visually distracting, so in most cases you will want to reduce noise in your photos.
However, if you reduce noise too much you may unintentionally reduce image sharpness.
ACDSee Pro 2 supports median noise removal. This method of noise removal is called median
noise removal because a mathematical algorithm identifies noisy pixels in a photo and adjusts
their values based on the median (or middle) value of neighboring pixels. Median noise removal
is useful for reducing Gaussian noise, which is the most common type of noise in digital
photography because it originates in a digital camera's image sensor.
You can apply median noise removal to all of the pixels in a square area, to pixels along
diagonal lines, or to pixels along horizontal and vertical lines. ACDSee Pro 2 also has a hybrid
option, which you would use if you want to apply median noise removal to more pixels in a
photo, or if you want to reduce the color variations that are sometimes caused by noise.
Removing noise from an image
You can use the Remove Noise filter to remove noise from your images while preserving details
that you want to retain.
To remove noise from an image:
1. In Edit Mode, on the Edit Panel, click Noise, and then select the Remove Noise tab.
2. Set the options as described below.
3. Do one of the following:
x Click Done to apply your changes and close the Remove Noise tool.
x Click Cancel to discard all changes and close the tool.