Registax Mac Download10/15/2020
Here I choose the Reference Frame menu, and change the Frames option from the default of 50 to between 200 and 300.By submitting this form, you are consenting to receive marketing emails from: American Astronomical Society, 1667 K Street NW, Washington, DC, 20006, You can revoke your consent to receive emails at any time by using the SafeUnsubscribe link, found at the bottom of every email.But extracting the most detail from the raw images produced at the telescope takes patience and skill, not to mention the tools available today for your digital darkroom.
Author Don Parker created these stunning portraits of Jupiter, Saturn, and Mars using webcams, a 16-inch Newtonian telescope, and the techniques he describes here. This is due in large part to the simple, inexpensive webcam, which has enabled amateurs armed with modest telescopes to produce images of the planets that rival those captured with large professional instruments ( ST: October 2005, page 115). The secret of the webcams success is that it can produce images with very short exposure times, perhaps one-tenth of the durations required with conventional cooled CCD cameras. This means that webcams can beat the seeing with planetary imaging and capture sharp images during fleeting moments of atmospheric tranquility. Webcam frames are noisy when compared to those from cooled astronomical CCD cameras. But because signal increases directly with exposure, whereas noise increases only as the square root of exposure, you can stack lots of frames to produce an image with a much higher signal-to-noise ratio than that of any individual frame. And not every frame you record will be worth keeping, so before you stack images you need to weed out the blurry ones. Sorting and stacking thousands of images manually would be about as much fun as undergoing root-canal surgery Thankfully, there are computer programs available today that will do this job of planetary imaging automatically. Careful image processing using the tools of the digital darkroom is every bit as important as acquiring high-quality webcam frames in the first place if you want to produce highly detailed and scientifically useful images. I frequently employ several different programs and planetary imaging to process my images, because no single program yet contains all the tools I find necessary. Sean Walker described its key functions in his review of version 3 in the December 2005 issue, page 94. ![]() By selecting an averagequality frame from an AVI file and increasing the FFT Spectrum radius value, higher accuracy can be achieved during the initial alignment. ![]() If the seeing was good during the movie clip, Ill instead choose a smaller Alignment box centered on an interesting planetary feature, such as Jupiters Great Red Spot or an albedo feature on Mars, for my registration point. Once Ive chosen my alignment point and Quality Estimate Method, a window opens that displays the FFT (Fast Fourier Transform) Spectrum of the registration point. I usually end up with a better stack if I decrease the radius of the FFT filter, so that it displays a larger target area than with the default setting (Figure 1). If I used a color webcam to record my target, its important to convert the flat frame to monochrome before applying it, or else the results will be unusable. If the lines intersect, go back a step and decrease the FFT Spectrum radius, then repeat the alignment process. After a few minutes, RegiStax will display the results of the Initial optimizing run, showing two lines in a window: a red one representing image quality, and a blue one displaying the registration difference between each frame. I try to end up with two roughly horizontal lines, though this isnt always possible (2). If the lines intersect closer to the left of the graph, I may adjust my earlier settings and repeat the alignment routine.
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