The images are located on my own private Server, I pay for since 2004. So I can be sure they won't get lost. This is not very cheap, around 1500€/year, but well ... That's actually also the reason I don't use dtube. Uploaded over 100 vids and none of them is working anymore.
So I switched back to youtube and martin-kuettner.de (my domain) to host the images/videos. I want the content still beeing up in lets say 1..2 years. I know steemit is a short term platform and I really hope the devs are going to change that in one of the upcoming HF's. ;)