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These pages may take a while to load as I wanted to include good resolution in the images included. Updated 24th March 2003. The techniques I use to produce the images are specific to the equipment software I use. In order to duplicate any of this you will need the following equipment and software. Having said that the actual processing technique that I use comes mostly from Ron Wodaski's book The New CCD Astronomy. I would recommend this book to anyone as it covers all aspects of processing in a lot more depth, with many tutorials. This is a guide to get people started, and it is also what I do right now (11th Feb 2003). My processing techniques change fairly frequently as I get better and better at it. So use this by all means, but remember I am have only been into CCD astronomy for a couple of years, and there are people out there who are a million times better than me. 1. MX7C Camera (with Star2000, but the techniques described will work with or without). 2. Astroart 3. Adobe Photoshop 4. Eddie Trimarchi's fits plugin. These techniques are really to help beginners get the most from their MX7C quickly, and no doubt there will be many more ways to produce better images, but this is the way that I use now. 1.Image and Calibration Frames Required. There are 4 different images that you will need to produce a finished image: The Object Frame - This is the actual image. These frames not only contain the object of interest, but also noise that the camera generates, uneven gradients due to the telescope / camera configuration, and dust specks anywhere through the imaging train. A Dark Frame - this is an image of all the unwanted signal in the raw image. This comes from the thermal electrons building up in the chip, the readout noise that the camera generates, hot and cold pixels (faulty pixels), and in particular with the MX7C and Star2000, the readout noise from the guiding frames. A Flat field - This is a map of the sensitivity of the chip, a map of the dust specks, and a map of the unevenness of the optics. A Flat Field Dark - This is the same as a dark frame as described above, but matched to the Flat Field. The Object Frame This is a raw image from the camera. You can see that it is very grainy and you can also see the vignetting, and a few hot pixels. I have taken 162 of these frames and we will create from these a single colour image of M43.  The Dark Frame. The dark frame is created by covering the telescope with the lens cap and exposing for the same length of time as the object frame and under the same conditions. For this example the object frame is of M43 and exposed for 60 seconds self guided with 2 second binned guide frames. The dark frames were taken immediately afterwards (as close to the same temperature as possible) and were guided identically, but with the x and y checkboxes unchecked, so the telescope does not respond to a missing guide star. This is one of the Dark Frames that I took. Note the graininess, this is due to random noise. Unfortunately not all the extra signal that is generated by the camera is predictable, so to counteract the random noise we must take multiple images and average them together to average the random noise. Also note the left edge brightens, this is noise generated by the guiding frame being read out every 2 seconds. Also you can see a map of the hot and cold pixels. The Flat Field. The flat field is created by taking an image of a uniformly lit background. There are many ways to create these, but I use dusk and dawn to create them. The camera needs to be at roughly the same focus as you have used for the object frames and must be in the identical position, so sometimes it is only practical to take flat fields at dawn. I turn off the motor on the telescope drive so as not to capture stars in the same place, which would ruin the flat field. What we are trying to achieve is a map of each pixels sensitivity to the same brightness. In my optical train I have an f/3.3 reducer which causes vignetting - this is a radial gradient, brighter towards the centre and darker at the edges. I took 70 x 10 second flat frames at dusk, and a further 150 x 4sec flat frames at dawn. I always take a lot of flat field frames, because they do not take up any imaging time and when you come to process your images and find a problem with the flat field frames, you cannot retake them another night (unless your camera is permanently attached to your telescope). A 10 second flat field is below:  Notice the star trails where the telescope is not tracking, also again notice the graininess from random noise. To remove the random noise and the star trails I will average as many as possible together (but not at this stage), I have read many formulas about how bright each flat frame should be, but to be honest I will take 50 or so flats that have maximum pixel value between about 20000 to about 40000. The Flat Field Dark This is an image with the telescope covered for the same duration as the Flat. Again due to random noise, many images should be averaged. A single frame is below.  You then have everything you need - a number of object frames, a number of dark frames, flat field frames and dark frames for the flats. 2. Synthesising Colour Before we do any aligning or averaging, we need to synthesise the colour from all of our images (object frames, darks, flats and flat darks). I use Steve Hill's (or Mike Smith's) plugin for Astroart for Colour Synthesis. Once you open the plugin, a window appears, I seem to have the most success using LRGB, it is also important to select the correct format - in my case Astroart software, MX7C and interlaced are all checked on the select button. The rest of my settings are below:  Once set up click on the batch button and select all the images. The plugin then automatically saves 4 images per frame - R, G, B & L. NEXT | ||