Saving files and creating a "macro"

[tinkertool]

Thanks for the replies, it gives me some things to try out.

I am exporting at 50% because I want to post pictures of items for sale on various websites (Facebook marketplace, Craigslist, etc.) and the resulting images seem much smaller and of acceptable quality. Also I may not be capable of telling the difference -- for example in the airliner photo response above I couldn't really see any difference offhand. You can tell I'm not a graphic artist.