Photography woes

Photographing my work is like a comedy of errors. Every time I set everything up, it begins to rain! Today is no exception. At least I got one piece shot before I had to quit.
But, first I used a gray card to get the settings. I set the camera for aperture mode, set the aperture at 8, and filled the screen with the gray card. Shutter speed indicated was 1/5. OK, I changed to manual mode, used those settings, and the exposure meter said +2.9. Naturally the image was wildly over exposed. I cropped this image, but didn't do anything else to it, not even rotate.


So, I set the camera back to aperture mode, and used the exposure meter to find the shutter speed. So this photo was taken with aperture 8, shutter speed 1/80, exposure meter -0.1. I clearly don't understand the gray card business!

When it stops raining, I have another piece to shoot. Let's hope it doesn't get rained on, too!