When people find out that it is possible to perform remote imaging with a CCD and computerized telescope they often ask if there is a way to do real-time viewing.  The idea is to see what the telescope sees (say, on a computer screen or TV) without having to be out at the telescope (which is handy when it's cold).  The answer is "not really, but...".

Not Really

When imaging deep-sky objects such as nebulae and galaxies, an astronomical CCD must build an image over time.  With the advent of more sensitive color CCD chips, one-shot color cameras are becoming popular.  These eliminate the necessity to take 3 individual exposures through red, green, and blue filters and combine them to make a color image.  The data then must be read out to a computer for display.  This readout takes several seconds so as to induce as little noise as possible.  Even on a fast system exposures will typically be 30-60 seconds each.  Then the images must be calibrated and adjusted using image processing software to get the best results.  Ideally, multiple images are stacked to reduce noise.

But...

This is extremely fast compared to the old days of capturing images on film.  A film shot might take 60 minutes and then the film must be developed, which even if you do it yourself takes a half hour or more.  If done by a lab this will take until the next day, unless you happen to have an all-night film processing lab in your neighborhood!  Then the film must be scanned into a computer.  Compared to film, CCD is practically real-time imaging!

Also, it is possible to use some CCDs or digital video cameras to remotely view in real-time.  Because of their lower sensitivity and faster read-outs video can only be used on bright objects such as the moon and planets, or the sun with proper filters.  With fast optical systems (say, f/4 or faster) it is possible with a very sensitive low-light video camera to image some of the brighter deep-sky objects (such as the Messier objects) in real time.  Also, come cameras are available which automatically stack multiple frames and download the composite image to a monitor.  This allows deep-sky viewing to be done in nearly real time.  To date these cameras are still black and white, due to the decreased sensitivity of color imaging sensors, but in all likelihood, real-time color imaging is not too far off.

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