Dan that was an interesting exercise at 1600. I think that is a less forgiving lighting/environment for 1600 than others.. I am not able to give any technical explanations to this statement, but it just seems to me like some environments are more forgiving to 1600 and even 3200 than others. There have been times when I've had my ISO set to auto with the whole range up to 3200 and have been content with the results. Better photographers would get better results, but for a pointer and shooter like myself, I am impressed with these results..
Here (1600) and
here (3200) are examples of what I mean..
I use the gimp a lot but don't have too many tricks up my sleeve, so thanks for the tutorials! I will be sure to visit them again then next time I am processing something where I need to accomplish the tasks you are covering there..
Roentarre thanks for the cc! I think I see what you mean about the imperfect circles, if you are referring to the lamps at the end of the glass partition. The lamps aren't perfect circles themselves, and because I was eating dinner with family I couldn't play around too much, but I see what you mean...
Any thoughts about the cactus shots? Did I add too much to them? I enhanced/manipulated the colors/contrast a lot just because I love wild colors, but my wife for instance prefers the more natural color interpretation of the edit that I attached below.