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| Setting up for a CCD imaging session should be as easy as you can make it. If you have a permanent observatory, you can leave everything together, that way you won’t need to make flat frames every night you image, also you don’t need to polar align very often, focus will be almost right every night and you don’t have to break everything down while you are half asleep. This is the perfect set up, but not possible for some of us. A semi permanent set up like mine is the next best thing. I image from my roof terrace and leave my tripod and wedge outside permanently, always polar aligned. I have a brick storage shed on my roof also to keep my telescope and accessories. I have a trolley on wheels in which I keep all my CCD accessories, so before dark I only have to carry my telescope 10 feet and wheel out the trolley. I put the whole thing together in 10 minutes and I am fairly well focused, polar aligned and ready to take flat frames at dusk. The last type of set up is a portable set up. This is one that you can take to a dark site, or one that you have to set up at home from scratch every time you want to image. All I can say about this type of set up is that if it is your set up at home, then find a way to make it semi-permanent. Mark where your tripod legs sit in the ground and never take the wedge off the tripod. Keep your accessories in clear plastic containers so they stay dust free and you can still see what is where. This is all just common sense to make it as easy as possible. Buy an adaptor for your CCD camera so that the whole imaging train screws together, if the camera moves during an imaging session, you have not only ruined that particular exposure, but your flat frames will be useless as well. Also if the imaging train droops slightly then you will not be able to reach perfect focus. Also buy a focal reducer, the LX200 is just not capable of imaging at f/10. The gears are just not quite accurate enough. The only people who I have seen be able to use the LX200 for imaging at the full f/10 focal length are those with adaptive optics devices (a deformable mirror that compensates for seeing and tracking errors). |
Connect Everything Power Lead to LX200 Hand Controller to LX200 Polar Align and Collimate the LX200 if necessary Train the PEC if necessary Attach the focal reducer to the camera (and focuser if being used) using an adaptor. Connect the cable from the camera to the camera control box. Connect the USB cable from the camera control box to the USB port on the computer Connect the power lead to the camera Connect the STAR2000 guider cable (if using) Connect the Focuser (if using) Connect any dew removing equipment Switch everything on except the computer. Set the max slew rate on the LX200 controller to 4 (increases lifetime and accuracy of the gears) Switch on the computer My personal imaging routine . Attach telescope to wedge, connect all cables and attach camera and laptop. Take a set of flat frames at dusk with telescope in Land mode, then a set of darks to match them. Slew to area of sky back in Polar mode and sync on the close bright star where my object of interest is. Fine focus the camera on the faintest star I can see in the finder. Centre target and choose guide star. Start guiding. Set up an autosaved sequence of 600sec exposures hires selfguide guiding 2.0 seconds 2x2 binned. Every hour until about 3am refocus due to temperature change moving the focus slightly. Change target as it is now getting low in the west, to an object that is in the east. Set up another autosaved sequence on this target. Go to bed Get up at dawn and take another set of flats Switch everything off and put it all away, leaving the tripod and wedge still out permanently. Every now and again I will set one night aside to recollimate, to adjust polar alignment, train PEC and spend the whole night getting dark frames. I find this worthwhile as then on imaging nights I can spend my whole time just capturing photons and with STAR2000 already stealing half your photons, I need all the imaging time that I can. | You are now ready to focus the telescope / camera. Slew to a bright star overhead. Enter Date & Time (if you have not already done so) in the LX200 hand controller. Roughly focus the CCD camera and centre the star in the image. Sync the telescope on the star. Make sure the finder is aligned. Switch on High Precision on the LX200 controller. Slew to catalogue number of object of interest using High Precision, this automatically syncs the telescope on the nearby bright star. Look through the finder and centre the faintest star you can see – this will be the ideal brightness to fine focus on. Perform your fine focus routine. Re-slew to your imaging target. Centre the target as you want. Pick the brightest star in the field to guide on (as long as doesn’t register more than 45000 at its brightest pixel with your guiding exposure and binning mode as this will start the antiblooming feature of the chip and can lead to inaccurate star centroid calculations) Start guiding and adjust if necessary the pixels per second on the x and y axis if over or under compensating. Set up for your desired sequence of images and start imaging. This may sound like a huge list of things to do to start your imaging session, but there are many parts of it that you will only need to do once in a while, such as polar aligning, collimation, rough focus of the CCD camera, align the finder, PEC training, adjusting x and y axis correction speeds of the guiding. So on a normal night this only takes me 10 minutes and I am always set up before it is completely dark, so no imaging time is lost. |