Night time and 20D

I was on my way home late Sunday night. I put the ISO 1600, with my 50mm 1.8 lens. I was really impressed with the quality.

Also that day I was taking some photos inside with no flash. Just tungsten lighting. The exposure looked great, but I was gettn disappointed because as I checked each shot in the screen, they seemed out of focus. But, when I got them home and viewed on my computer they were tack sharp. Anybody experience that?

No, it's usually the other way around for me. Sometimes what seems sharp on the screen would actually be out of focus when viewed on computer.

What you see only the camera screen is just a thumbnail image that's embedded in the main picture file. Were you perhaps zooming into the on-camera display? It'll always look fuzzy when you do that.