Much has changed in the last few years regarding the way in which planetary images are taken. Planetary imaging used to be one of the most challenging aspects of astronomical imaging, but new technology has now made capturing high-resolution pictures...
There are two ways to think of getting the "most" out of an image: capturing the faintest possible details, and capturing the finest possible detail. The ideal situation would involve getting an image with both extremely fine detail (high resolution)...
Imaging Comets There are basically two types of comets: faint ones and bright ones. The bright ones certainly get all the glory, and names like Halley, West, Hyakutake, and Hale-Bopp are all familiar to most amateur astronomers. Occasionally a fainter...
Imaging Asteroids While asteroids do not share the stunning beauty of their solar system cousins the comets, they are worthy CCD targets nonetheless. Only the most powerful professional telescopes have the capability to resolve features on the surface of asteroids...
Imaging Supernovae Professional astronomers distinguish between two main classes of supernovae. The distinctions have to do with the type of explosion occurring, how it is triggered, the resulting light curve and the atomic elements visible in the spectrum of the...
Mosaics are large, usually wide-field, images stitched together from several smaller images. The reasons for creating mosaics include obtaining a wider field of view with a small CCD and/or long-focal-length scope, and making larger image files for creating larger, more...
What is narrowband imaging? In normal color imaging, three filters (red, green, and blue) are used to separate the primary colors of the visual spectrum. Red, green, and blue (RGB) filters are designed to approximate the color sensitivity of the...
In the Image Processing Basics section on Calibrating Images we discussed only one type of image calibration -- dark subtraction. This is the most important calibration step, but not the only one that can be performed. Other techniques include using...
Combining images was covered briefly in the Image Processing Basics section. Here, more detail is given on methods for combining multiple images to increase detail and to reduce noise. Methods for Combining Images The simplest way to combine images is...
We touched on high-pass and low-pass filters in the Image Processing Basics section. Here we go into more detail on more advanced filters such as unsharp masking, low-pass filtering for noise removal, and filters for reducing image artifacts. Unsharp Mask...
well as other color image techniques such as LRGB and CMYK imaging. Advanced RGB Techniques The basic idea behind RGB imaging is to combine three images taken through red, green, and blue filters. This creates a full-color image. Since color...
The following is a simple procedure which can be used to enhance faint detail in an image while preserving detail within bright regions of an image. This is particularly useful for bright nebulae (such as Orion or the Swan) or...
