Hi Ken ... this was taken with a Sigma 150-500mm lens, ISO 800, 1/160 @ f-6.3. Unfortunately, I have to shoot through a window with double-pane glass, so it's not quite as sharp as it could be.
How lovely to have a bird like that so close to where you live.
Yes ... we are very lucky that on any given day, up to six Cardinals (3 male/3 female) might show up at the same time. (they really love the peanut butter that we spread on the branches outside our window!)