Wow talk about coming a long way. I have always been a visual astronomer, and to this day still yearn for my dark sky jaunts when I can hunt down some faint elusive galaxy (or galaxy clusters) with my light bucket, my GS 10" f/5 dob for sketching. But lately I have been getting the itch to dip my toes, or so to speak in some light and easy going astrophotography (if there is such a thing!). The word astrophotography usually conjures up images of super expensive, highly precise mounts and equally expensive CCD cameras and APO scopes. Then there is the steep learning curve associated with it. Well there is also the other side of the coin, afocal and webcam astrophotography of solar system (i.e. bright) objects. While that is cool, some rudimentary deep sky astrophotography is also doable. One might still need a tracking mount and some sort of device to hold the camera in place. This would not have been at all possible in the past with film cameras as one would have to expose the film for long periods of time to get a decent photo. This is where the super expensive and super precise mounts come in. With the advent of digital cameras, one can now mimic long exposures by taking short term exposures and then digitally "stacking" these images together to produce a chimeric long exposure. There are also many software packages that enables one to modify and enhance their images, the best being Adobe's Photoshop. So yes we have come a long way from the so called "dark ages" of astrophotography.
In order to do some basic astrophotography, one would need a digital camera that has a manual setting (to focus starlight at infinity). One also needs some sort of self built in timer to minimize camera shake. Any extra functions such as the ability to control the ISO settings and the exposure time (most digital's have this functionality anyway) will greatly improve your chances of getting workable images.
My initial forays into afocal imaging was met with frustration and grief. This was partly due to me using a non too suitable digital camera. I originally started imaging using my old 5 megapixel Kodak P850 (regular CCD chip). This camera has served me well over the years and I have taken some really spiffy wide angle shots of constellations, comets (McNaught and Holmes) and also some lunar eclipses by holding the camera up to the eyepiece. Seeing how I now had something that could hold the camera to the eyepiece, I though things would be easier. Wrong. Getting the camera lens to align with the eyepiece FOV was quite painful (becomes easier with practice). Also the chip on this camera was not very sensitive to low light conditions. So after playing around with the setup for a couple of weeks, I gave up as the results I got, even with bright objects like the Pleiades cluster and M42, the great nebula in Orion was dismal.
Enter my new camera, the Kodak z990. I bought this camera due to the fact that it was the first Kodak camera to have backlit CMOS sensor as opposed to a regular CCD sensor. This translates to excellent low light shooting capabilities. I have tested this time and time again and the results are nothing short of astonishing. I can hold the camera by hand and shoot constellations from a suburban setting and still get some pretty spiffy shots. With this camera I seldom have the need to resort to flash photography! Needless to say I was itching to try afocal photography again on those mentioned objects. Boy was I not disappointed. I played around with getting the magnification and exposure right to minimize star trailing. With the Orion Skyscanner with the 20mm in at 20x, I found I could push the exposure time up to about 8-10 seconds without significant trailing. Best results however were obtained from 5-6 second exposure. I also played around with ISO settings and generally ISO800 and ISO 1600 gave the best balance of brightness. Also it helps greatly when you can set a 10 second timer to reduce vibration and shakes that show up in your images. With these settings, I managed to capture some of the pastel hues in M42. Bear in mind that these are not stacked images but single images! Can't wait to try imaging under pitch black skies!!!!!!
So what's next on my list? I hope to try and shoot for some of the brighter planetary nebula's such as M57 and M27, the ring and the dumbbell, globular's M13 and maybe some of the brighter emission nebula's like M17 and M8, the swan and the lagoon nebula. Also I would like to try for some brighter galaxies from dark skies sites.....that is when summer rolls around ;)
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