Hi, I've taken the liberty of inserting a pic from another post of yours using the image URL received by (in Firefox) right-clicking the image and selecting "copy image URL" from the context menu:
EDIT: Took me too long to edit the post, see the poster's below.
Were do you get the URL you wish to insert? In the original, it was a link to the original image including a re-sizing tag that shrunk it down to 180px, which seems to be included in the "preview image / thumbnail for fora" link option found under "Share" (I can't change the display language to English, but it should be something like that).
You would want to use the "Direct Link" option. If you insert this in a post and frame it with the [img] tags, then it will only re-size it to our forum-set display limit of 1000px width.