Taking CCD Images

Exposure Times

Determining the proper exposure time is as much an art as a science.  For deep sky imaging, suffice to say that longer is always better, at least until light pollution starts to overwhelm the image.  From a very dark location, or with a narrowband light-pollution filter (such as a Hydrogen-Alpha filter), the only limit may… More »

Guiding Tips

Using a self-guiding CCD camera, the Track & Accumulate function, or a CCD autoguider, involves acquiring a guide star and then calibrating the autoguider in order to make corrections for slight tracking errors.  Below are some tips for more easily finding guide stars, choosing appropriate stars, calibrating, and troubleshooting. Selecting Guide Stars If you are… More »

Capturing Images with a Webcam

Taking pictures with a webcam can be one of the easiest ways to get into astronomical imaging, and it can yield incredible results.  Since webcams are used to image the moon and planets, factors such as light pollution and tracking accuracy, which normally affect deep-sky imaging, become unimportant.  This makes webcam imaging a possibility for… More »

Color Imaging

It is recommended that you spend some time taking black and white exposures to learn the basics of focusing, finding, and capturing images.  Once you have these techniques down you are ready to start taking images in full color!  For a discussion of “real color” as it relates to astronomical images, see the Advanced Theory… More »

Capturing Images

The telescope is now focused and we’ve determined how to find and center a target.  Now the fun part! The following section walks you through the basics of taking basic exposures in black and white (the next section covers color).  For specific steps with certain software packages, visit the Software Instructions section. Short Shots –… More »

Finding Celestial Objects

Computerized telescopes are becoming increasingly popular.  These telescopes make finding celestial objects extremely easy.  However, there are still many non-computerized scopes out there, and even for users of goto scopes there are some tricks necessary for getting the exact picture you want. Finding Objects Manually Finding targets for CCD imaging is very much like hunting… More »

Choosing a Target

When you first start imaging, you will probably want to take pictures of the objects you are familiar with from visual observing.  This will allow you to see your favorite objects in spectacular new detail.  Eventually, you might also want to image the things you cannot see visually through your telescope.  A perfect example of… More »

Aligning a Computerized Telescope for Imaging

Note:  For specific instructions on aligning various models of computerized telescopes, see the Aligning a Computerized Telescope section of theTelescope Basics site.  Below are general recommendations for aligning for CCD imaging. Most computerized or goto telescopes need to be aligned after the CCD camera is in place.  This is due to the fact that a… More »


Accurate focus is critical to obtaining high-quality CCD images.  One of the many advantages of CCD imaging over film astrophotography is that achieving focus is much easier with a CCD camera.  However, there are still some tricks to getting a precise focus. Note:  Since this is the Basics section, the following discussion keeps focusing simple… More »

Balancing for Imaging

Properly balancing your telescope is one of the most important steps in setting up to take CCD images.  Improper balance is also one of the biggest sources of problems for imagers.  Taking some extra time to understand the concepts behind balancing and to correctly balance your telescope will definitely pay off in the end.  Balance… More »

Setting Up the Computer

While setting up your computer for CCD imaging is pretty straightforward, there are a couple tips and tricks which can prevent problems you might run into. Laptop Settings It is important to turn off certain power-saving features before beginning CCD imaging! If your computer goes into sleep mode while an image is being taken it… More »

Attaching the CCD Camera and Accessories

While this seems like a straightforward procedure, there are some tricks to assembling all the imaging accessories which will help you avoid problems during an imaging session. Mounting the CCD Camera There are quite a few different ways to attach a CCD camera to a telescope.  It mostly depends on what you wish to image,… More »

Polar Aligning your Mount for Imaging

Accurate polar alignment is critical for CCD imaging.  Field rotation, a trailing of stars near the edges of an image, can result from improper polar alignment.  Even short exposures such as planetary images can benefit from good polar alignment as there will be less drift from one image to the next during a sequence, keeping… More »

Assembling the Telescope

Since there are different requirements for imaging than for visual observation, the setup of your telescope will likely be slightly different for CCD imaging than you may be used to for visual observing.  Everything must be more precise when it comes to imaging:  alignment, balance, tracking and focus all must be more accurate than is… More »