OK, embryo rescue is a technique used to help embryos grow that would otherwise not fully develop. I just read the wikipedia article on it, and it is fairly accurate in my experience:
When I try I will start by opening up tomatoes or peppers (whichever I use as female parent) daily after pollination to see how the embryos develop.
Then I will pollinate pepper with tomato or vice versa and take embryos again at different days to see what they look like, then decide on a number of days to harvest after pollination.
Then start pollinating.
When I did it before, I would pollinate once a week, and harvest once a week everything that was 3 weeks after pollination.
I had 4 tags color coded so each week I would harvest all tags of a certain color and take them into the lab.
Once in the lab, ....more later