[flowerpower]

I made a brave decision this morning; my freezer is full to bursting, and the larder is the only storage place left in the house, so all 6 jars went back into the pan this morning together with more sugar (with pectin).

The original recipe called for half the sugar to the weight of fruit, so I guessed how much more I would have to add to make it up to "full strength" jam. I then boiled the living daylights out of it! (Well, fast boil for 5 mins). I now STILL have 6 jars of rasberry jam (spooky eh?) that should last... hopefully!

[Poolfield2]

Hope it works out well for you 

[Spana]

Just out of interest, did the first lot made with half the sugar set ok. 

[flowerpower]

Yes, Spana, the jam set - but as a conserve as opposed to a full set jam. ie it was a lose set jam!
Hope that helps