Cleaning the Filter Wheel for the STX 16803 (and SBIG filter wheels in general) is fairly simply. However, as with any optical instrument the task should be undertaken with care and patience (something not to be rushed).

You will need a clean workspace- preferably in an environment with still air. Gloves are not required, but are certainly good etiquette for the job. Described below is the “Quick Clean” process which uses a dry microfiber cloth. You will need to remove the camera from the telescope and have a set of Allen wrenches to disassemble the filter wheel. A bright light source (flashlight or work light) will also help. As a general rule, do not talk (or eat) when doing this task.

1. Unscrew the 6 screws holding the filter wheel enclosure together.
2. Familiarize yourself with the internal parts of the filter wheel and make certain each part is working. The motor is mounted to a hinge that is pressed against the outer rim of the filter wheel by a small spring. Disengage the motor by pulling it away from the filter wheel. (WARNING: Do not lose that small spring! It is captured in a small recess… but is easy to lose if the filter wheel is handled without being engaged to the motor.) Note that the rim passes between a “U” shaped sensor.
3. Carefully remove the three bolts that hold the filter wheel to the spindle in the center.
4. (Now the tricky part…) With your right hand disengage the motor with the back of your fingers/hand and simultaneously grasp the filter wheel between your fingers of both hands.
5. Gently rock upward and once free of the spindle slide away from the sensor. Do not apply any force to the sensor. The filter wheel is a machined/precise fit to the spindle but it comes up relatively easily. If it is hard to do, please stop and see what the issue may be.
6. With the microfiber cloth lightly (just the weight of the cloth itself) wipe across the surface of the filters on both sides. If the filter wheel is held somewhat vertically between your hand and your body it is possible to clean from top to bottom. Use a top-down motion for each swipe.
7. (OPTIONAL) Using the smallest Hex wrench open the camera shutter by sliding the wrench between the shutter and the underside of the camera body window. Slightly rotate the wrench so the the small side acts as a “hook” to gently catch the edge of the shutter. Do not over rotate wrench and interfere with camera parts underneath. Pick up the camera body and clean the window with a single swipe (or two). After cleaning immediately work to put the filter wheel back on and protect the CCD window from gathering more dust.
8. To reassemble the filter wheel first position the spindle hub so that the bolts are in the same orientation you intend to install the filter wheel. This part moves and you need to match the holes.
9. Again grasp the filter wheel and with the back of your right hand push the motor away.
10. First attempt to put the rim of the filter wheel between the sensor and then center and place on the spindle.
11. It is likely the holes did not align perfectly. With the smallest Hex wrench insert into the holes and by “jiggling” align them. If you cannot see the bottom hole on the spindle hub- unfortunately it means you missed and you must remove the filter wheel- realign the spindle hub…and try again!
12. Once on the spindle hub tighten the 3 bolts to secure it. Test the wheel by disengaging the motor and spinning the filter wheel. If it is spins freely without rubbing the sensor or anything else you are done! (If not, you need to reseat the filter wheel.)
13. Reinstall the filter wheel enclosure cover.

The filter deep clean process is similar to the method used to clean eyepieces and other small optics.

1. Using Tek wipes (for all steps) gently apply LiquiNox to break up oils and residue.
2. Lightly dry with new Tek wipe.
3. “Wash/Rinse” with distilled water (new Tek wipe)
4. Lightly dry with new Tek wipe.
5. If surfaces does not dry cleanly, perform another rinse dry cycle.
6. Follow up with Isopropyl alcohol. Use just enough that as you wipe it evaporates immediately behind the swipe. This is an optional step if things really look good.

Do the above to each side.

Below is an example of before/after pictures of a Deep Clean (bottom right filter).

Performing a deep clean on the CCD window is not recommended in general. This should be done in a laboratory setting or controlled environment by a skilled technician.