We are often asked how to best clean the surface of the CCD chip. Below, for example, is a close-up of the front plate of a DMK 21AF04.AS, showing the CCD chip behind the cameras' C/CS mount. Accessing the CCD chip can be tricky.
Following is a list of the preferred methods to clean the surface of the cameras' CCD chip:
1) Compressed Air From Air-Blower
Compressed air is usually sufficient to remove most foreign bodies from the surface of the CCD chip. We recommend using an air-blower, such as from Edmund Optics, and not compressed air from an aerosol. Compressed air from an aerosol may contain other chemicals (propellant, water, oil etc.) which could damage the surface of the CCD.
For details, see www.edmundoptics.com.
2) Hama Lenspen MiniPro II
A company called Hama manufactures a product, which is ideally suited to the task: Lenspen MiniPro II. It is available online and from most well-stocked photography stores. One side of the pen has a brush on it, while the other, a small cleaning surface. The later is suited to efficiently removing dirt and fingerprints.
For details, see www.amazon.co.uk.
3) Microfiber Cleaning Cloth
Although a microfiber cleaning cloth is a very viable option, it can be tricky to get the cloth onto the surface of the CCD chip through the camera's mount opening. A cotton swab (UK: Q-Tip) can help here.
4) Pure Alcohol (at least 90%)
This can be purchased from most chemists. Never use Isopropanol, as it draws moisture from the air, which results in streaks on the surface of the CCD.
5) Alcohol Substitute
Instead of pure alcohol, Methanol or a liquid called Eclipse can be used (Eclipse is essentially Methanol). However, we do not recommend this approach, as Methanol is highly poisonous.
6) Combination Of All The Above
Of course, all approaches can be combined!
Do not worry about touching the glass in front of the CCD chip. It is pretty robust. Only by rubbing glass, sand or diamond on the surface can it be scratched.
If you have any questions about cleaning your astronomy camera's CCD chip, please do not hesitate to contact us.