User manual CELESTRON NEXIMAGE

[. . . ] Table of Contents Quick-Start and Tutorial Imaging Basics Registax User's Guide Troubleshooting Quick Start Make sure your NexImage comes with all of the following: 1. 25" Barrel USB Cable Installation CD Rom 1. Plug camera into the USB port of your computer. Double click the Amcap icon to start the program. Make sure "Preview" is selected from the Options menu. [. . . ] Steadily moving objects can be easily followed, unless they move too fast. The largest movement between images the program is able to adjust directly problems is about half the size (in pixels) of the alignment-box. When you enable the predict option, the program will be able to trace faster moving objects as long as they move in a constant direction. When the object moves in a more random fashion do NOT use the predict option, instead increase the FFT-size to keep the feature easier in view. If the misalign warning is set you will be notified when the program thinks it looses track of the alignment feature, then you will be asked to realign the image. If the object you want to register moves over the image-space like you can see in the above example you will need to set the "track object" option. Track object will try to keep track of the object by using the information of the previous shift. If the object slightly moved to the left we expect it to be at least shifted to this position in the next frame also. If the object moves in a steady fashion this feature will keep track of the necessary alignment. But for steady moving or fast moving objects the "predict" track might also be helpful, With this feature the program makes an expectation of the objects position based on the last shifts. If the object moves fast or in a random way over the image the user is advised to use a larger FFT box. Auto-optimization ­ This setting is associated with three controls in the optimizing options panel (#15). During optimization the pixel-by-pixel difference between the image and the reference image is measured and minimized. Setting the "Optimize until" thumbwheel (%) will make the optimization run until the difference between successive runs is less than this value. 19 During optimization the program searches for the "best fit" in a box with a dimension set by the search area control. At every optimization run (through all the frames) the program searches the best possible shift for every frame versus the reference frame you selected. Every run starts with the latest optimal shift. When you choose a small search path the program will process faster but the optimizer might miss the perfect alignment position. On the other hand if you search a real large area for every optimization run, it will increase the amount of time it takes to for each processing run. A search radius of 5-10 pixels is usually sufficient. Lastly you can set the lowest image quality (relatively to the best image) that you want to be optimized (and later on stacked !!). Setting this to 0 will optimize all images, setting it to 100 will only optimize the single best frame (not recommended), a setting about 75% often is useful. Be aware that when processing a set of FITS files it will be wise to include them all, set the lowest quality to a low value to arrange this!! [. . . ] Cropping ­ You can crop part of the image by drawing a box around the feature you want to work on. Both clipboard and saving will then only work for that area unless the cropping checkbox (appears only when you draw a box) is unchecked. Be aware that this crop will not follow the rotation so first rotate and only then use this. The program will show the X, Y position of the top-left corner and the X, Y dimension of the crop you are creating. [. . . ]