Forum etiquette says something like an hour or two is fine, or others posting in-between your posts - or indeed in response to another's post to you. To be honest, people rarely take notice of posts about double posting on image threads, as posts with twenty plus images can be slow to load...@MeanElf I got told off for double posting 2 in a row Is there a limit to how many posts you can put on each day as I have a few more ready but don't want to post too many and annoy anyone?
Welcome to DC! Some truly beautiful photographs there, especially the electric car (whatever it is called...) that is drifting.