User manual SBIG CFW8-A

[. . . ] You can take equal duration exposures in the Red, Green, or Blue or match the exposure duration of each primary image to the brightness of the object. Typical ratios of Red : Green : Blue are 1 : 1 : 1. 6 to match the exposure to the CCD's sensitivity although accurate color balance should be done for your system with neutral grey objects or "white" G5 type stars. Each of these images should be dark subtracted1 and should be saved with a name that indicates the color of the filter (e. g. , M51R, M51G, M51B). Note, however, that different software programs may handle tri-color files differently and the naming convention you use is dictated by your software. [. . . ] Save these in case you decide to later use the CFW-8A with the T-Thread coupler or with a different camera. Using the four 4-40 by 3/16 socket screws provided, attach the CFW-8A to the front of the ST-7/8. Make sure you use the provided screws whose length of 3/16 is required to SBIG CFW-8 Page 6 SBIG the ST-7SANTAplate withoutINSTRUMENT GROUP BARBARA thread into front breaking through the blind taps. Alternate temporary attachment of CFW8 to ST-7/8/9/10 ST-7/8/9/10 users may also mount their camera to the CFW8A by unscrewing the camera's T-Thread nosepiece and screwing the Filter wheel onto the camera with an optional male-to-male T-Thread coupler. Proper clocking of the CFW-8A relative to the camera is achieved by loosening three set-screws at the font of the camera rotating the CFW-8A into position then re tightening the 3 set screws. ST-7/8 CFW-8 Making the Electrical Connection The CFW-8A has a cable that comes out the side that needs to connect to your camera electronics. The CFW-8A gets it power and positioning information from the camera thru this connector. If you're using an ST-4X, ST-5 or ST-6 the CFW-8A is supplied with a 15 foot cable that you plug into the AUX port on the camera's CPU. The AUX port is the 9 pin connector adjacent to the COM port you use for communicating with the PC. If you're using an ST-7/8/9/10 the CFW-8A is provided with a short cable that plugs into the camera's 9-pin telescope connector adjacent to the cable connecting the ST-7/8/9/10 to the PC. SBIG CFW-8 Page 7 SBIG the CFW-8A connector has the phone-jack connector SANTA BARBARA INSTRUMENT GROUP Additionally, that allows you to connect to the telescope for tracking and Self Guiding. If you ever decide to connect the CFW-8A to an ST-4X, ST-5 or ST-6 you can buy a 15 foot 9 pin extension cable to extend the short cable back down to those cameras' CPU. Attaching to the Telescope At the front of the CFW-8A you can attach any T-Thread based adapter that will connect to your telescope, including the nosepiece from your camera. When using a nosepiece to slip the camera and filter wheel assembly into an eyepiece holder, you need to pay careful attention to insure the weight of the filter wheel with the camera attached is held in place with the eyepiece holder's retaining screws. SBIG also sells an optional T-Thread Visual Back Adapter which screws directly onto the back end of the popular Schmidt-Cassegrain telescopes. After attaching the camera/filter wheel combination to the telescope, you should t hen drape the Camera's head cable over the fork of the telescope and clip it in place so that the cable doesn't drag on the ground as the telescope rotates. Also avoid hanging the camera head and filter wheel by the cables as this could overly strain the cables. Positioning the Filter Wheel The motorized CFW-8A filter wheel is positioned using commands in the CCDOPS software's Filter menu. The unit does not require calibration like the older CFW-6A and is auto-homing at power-up. You need to tell the CCDOPS software that you are using the CFW8A and this is accomplished by selecting the CFW-8A as the filter SBIG CFW-8 Page 8 SBIG the Setup commandBARBARA INSTRUMENT GROUP SANTA wheel type in of the Filter menu. If you have an older version of CCDOPS that does not show the CFW-8A you can still use the CFW-8A by first erasing the FILTER. CFG file in the CCDOPS directory (the software will create a new one for you) then select the CFW-6A type filter wheel in the Setup command. There are individual commands in the Filter menu with hot-keys for positioning the flter wheel. Also the Camera Status window i shows which filter is currently in position, and this information is recorded with images when they are captured. You can rename the filters using the Filter Setup command. If you have removed the filter wheel from your camera or removed the filter from the magazine you can select the None command in the Filter menu. The None command doesn't position the filter wheel, it just tells the software that you aren't using a filter at the moment. If you run without filters for a period of time you should use the Filter Setup command to select the "None" type of filter wheel. Remote Shutter Operation with the ST-4X and ST-5 ST-4X and ST-5 users can use the CFW-8A as a remote shutter for taking dark frames. [. . . ] The filters screw in from the bottom and the top has the optical alignment pins. As viewed from the top the filter positions are shown in the figure below, noting the position of the double-pinned position adjacent to position 3: 1 2 5 3 4 Top View of the Filter Magazine The filter wheel is reassembled in the reverse process. Rotate the filter magazine so that the alignment pins straddle to either side of the motor then tilt the magazine into place and drop it into the back of the housing. Be careful to not bend the axle in the process and also make sure the magazine is inserted with the filters down towards the camera) and the alignment pins up. [. . . ]