I shoot in dim light most of the time. I use a 50 1.8 and and just added a 85 1.8 for basketball . I own a 30d
Here is what I do, but I am not improving anymore...
I get into a gym, first I look at the speed I get at iso 800 at f 1.8. If I get anything over 1/500, I go to f 2 or 2.2 to help me with sharpness issues. Then I do a costom white balance with a white object on site.
Then I check the exposure and I shoot with the camera on AV mode at a minimum speed of 1/400. I love it when i can use iso 800 but its RarE. I dont like the noise at iso 1600 and over. I sometimes do well...other times I am wasting my time. I used the * for a while to focus with my 20d, did not change the settings for this one. I find that my 70-200 IS focuses well compared to my other lens but the 1.8 is very practical in low light
You pros out there, what is your routine?
I would love to do better