So I had trouble on the TEM yesterday. Everything started out great. I got the microscope aligned quickly, and I found the area of interest on my sample relatively easily. Then I tried to get a background EELS spectrum. I record my EELS spectra at 0.05 eV resolution. To do that, I take a background spectrum at 1.0 eV, and then center the peak (from the electron beam) where I need it to be to get the higher resolution. It's kind of like when you center your thin section under low magnification in a light microscope, then change to high magnification. The spectrometer has 1024 channels (i.e. pixels), and I need to center the peak somewhere within the first 100 channels. For some reason, I couldn't do that. I could move the peak up to higher channels but not below about channel 150. That means I couldn't even take spectra at 0.3 eV resolution, let alone 0.05 eV. I think one of the apertures is misaligned, but I don't have access to adjust it. So my TEM session was bust. I just took a couple of pretty pictures and left. I have no idea when this problem will be fixed, but it is being worked on. There's one other TEM that I know how to operate, so I'll try that one next week.

This is an issue for me because I need to collect some EELS data before I leave for GSA on the 15th.