- Different brands of SEM have slightly different processes for photography. To take a photograph you may need to adjust the contrast and brightness against a scale inbuilt in the machine, otherwise you can rely on your eyes. You will need to set the information up that you want at the bottom of your photograph, such as magnification or a scale bar. The basic principle involved in taking the photo is that you slow the scan rate of the beam down. Normal viewing occurs at “TV” rate, but the slower the scan rate, the more signal you collect as the beam scans the sample. This leads to a better, less “grainy” or “noisy” image.
- Once the photo is taken you need to save it to a file for later access.
- Now continue using the machine or remove the sample and replace it with a new one. To change samples you will need to return your sample to the settings necessary for sample exchange. In some machines this may involve returning to an initial setting, or exchange position. Turn the beam off and let air into the chamber.
- Once you have finished your viewing session, take your sample out of the chamber. There may be a specific way the laboratory manager wants the machine left. You will be instructed in this. Otherwise, just remember to leave the beam off and the sample chamber evacuated (empty of air/ under vacuum).