Using this recipe, I made up half a batch. I think I used just a little too much water as it took an age to get down to the correct consistency. I would recommend just covering the blackberries with water, chopping the whole apples quite small and just putting them on top. That way, you won't add too much water.
Other than the long boil time, it looked and smelled wonderful. Sieving the stewed fruit to remove the pips and rubbish took about 15 minutes as you really need to make sure as much fruit pulp is squished through the sieve as possible before measuring and adding sugar. There really shouldn't be much rubbish left in the sieve.
Anyway, this is how much I got from the half batch:
Have a lovely weekend everyone!