rating

is it my imagination or is there a change in the rating system: a couple of weeks ago if i played someone in a 50 point range of my rating a loose would mean 10-15 points down: now that seems to have doubled to 25-30 points ... what happened?

The rating difference between players is not the only factor. There is also the rating deviation. " ... your rating moves less when playing an opponent with a high rating deviation because his true rating is less known. "

There could be a problem but perhaps this is the reason the ratings loss is different from opponent to opponent.

no change. perhaps your RD has gotten larger as you haven't played as many games. or your opponents have smaller RDs. lots of stuff goes into ratings!