why the 9000 & 8000 ISO, are you testing??
Experimenting with stopping down to see if it will solve some of my problems, and my images are noisy compared to others shooting in similar circumstances. So, yeah, kinda testing to see what I find acceptable. I would rather play with it when I am shooting common birds in the yard than trying to go on a field trip and coming home with bad images. Usually, I won't go above a certain ISO, but I don't always get good results doing that. I can read all the articles and look at images, but I need to get my hands on it or the information won't stick. At one point I had it on auto ISO, but I don't know if this is one of them.
If I really wanted to do things right, I would meter the yard, use a gray card, and keep a journal.
I am about to start doing some controlled testing on my lenses as well to fix any focus issues.