Because CCDs are sensitive to the (near) infrared (IR), imaging in this part of the spectrum is remarkably easy. I use a simple Hoya IR filter bought from a camera shop. This filter appears as black glass, as it transmits no visible light, making it the ultimate light-pollution filter! Amazingly it gives your telescope remarkable penetrating power. Galaxies hidden behind the Milky Way, such as the Maffei/IC342 Group and their faint companions, can be successfully recorded from light-polluted sites (Figures 9.10 and 9.11). Many of these are so faint they have only been recognized in the last 10 years - yet we can image them! The Quasar images (Figure 9.1) are another example - their high redshift carries their peak emission point (Lyman Alpha) into the near infrared - perfect for us! This is what I meant by being smarter in image choice.
Selection of Hickson Compact Galaxy Groups.
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Compared to film cameras, digital cameras are easy to use, fun and extremely versatile. Every day there’s more features being designed. Whether you have the cheapest model or a high end model, digital cameras can do an endless number of things. Let’s look at how to get the most out of your digital camera.