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INTRODUCTION
| Come with me on a journey through space and time. As you browse the images on this site, you are looking deep into outer space, and consequently, back in time. Take any of the galactic images, for example -- M31 in Andromeda, one of the nearest "island universes" -- it is about 2 million lightyears distant, and the photons that gave birth to this image were travelling through space for 2 million years before striking the CCD chip in my digital camera. This image is M31 as it appeared 2 million years ago, long before the dawn of homo sapiens on earth! On a smaller scale, consider the Horsehead Nebula within our own galaxy, approximately 1500 lightyears distant -- this image, photographed in 2004, actually depicts the appearance of the Horsehead in 500 AD! If the Horsehead had been destroyed by some cataclysmic explosion in 2004, our descendants would not see the results until the year 3500! (give or take a few)... Now it is apparent from whence the name "Fourth Dimension Astroimaging" derives... If you've ever peered through the eyepiece of a telescope, however, you will instantly recall that the images you saw bear little resemblance to the images on this site. Our eyes are wonderful "organic" imaging devices. but even when looking in a large telescope, most celestial objects appear as dim and gray "fuzzies", totally devoid of color, and often devoid of detail. It is only through the magic of photography that our cosmos reveals its true character... These images are an example of "long exposure tricolor digital astroimaging." A digital camera, especially adapted for astronomy, is coupled to the telescope (I currently use 2 different scopes -- a relatively short focal length 4" refractor, and a longer focal length 12.5" reflector.) The camera, in turn, downloads the data directly to a laptop computer. Individual exposures are made through red, green, blue, and other filters, as an extremely accurate motor drive slowly turns to compensate for the earth's rotation. Each exposure can range from 1 minute to 30 minutes in duration, and a given object can require dozens of these component exposures, for a total exposure of at least 3 hours -- my record to date is a 29 hour exposure (over several days) to create the hydrogen alpha image of M27, aka the Dumbbell Nebula... The raw data is "reduced" to remove the effects of thermally generated noise, vignetting in the light path, dust near the CCD chip, and other problems. Then the component exposures are digitally superimposed, thereby greatly improving the signal-to-noise ratio, and allowing for very faint objects to be imaged with a wealth of detail. The resultant image is further processed to adjust the color balance, sharpen and/or blur selected areas, remove light pollution effects, etc. The time spent assembling the final image (after the outdoor work is complete) ranges from several days to several weeks!... The final product -- taken from a backyard suburban location in (light polluted) Bucks County, PA -- rivals that produced at professional observatories using traditional film techniques! Unfortunately, the learning curve to master this hobby/obsession is quite long and steep. I am still ascending the curve, and although I think the slope has leveled off, the peak is nowhere in sight. I remain ruthlessly critical of my images, and perhaps this is how it should be. I hope you will be satisfied with the results. I also hope you are satisfied with the "feel" of this website -- I included image descriptions that are easily understood by the non-astronomer, while also providing exposure data that could be useful to any imaging enthusiast. Please email any comments or suggestions. Thank you. Steven Mazlin, M.D. Fourth Dimension Astroimaging, LLC steve@fourthdimensionastroimaging.com |