i'm sorry i couldn't find the part were it tells how big pictures are
allowed to be here on Insim.
It's in the
Site Rules.
Signature pictures are allowed however they must be pg-13 and no larger than 250x50. Any signature pictures larger than this will be removed from your profile. If too many people abuse size/content then the ability to have pictures in your sigs will be removed
Picture limits are 600x600Pictures must be hosted by a 3rd party - eg
photobucket,
tinypic