Over the autumn I made several pots of crabapple jelly and crabapple and raspberry jelly as my tree was laden with fruit.
I didn't write the recipe down but as I recall, I basically followed
this recipe on youtube but added approx. half a packet of frozen raspberries to the pot of crabapples at stage one. At first I thought the raspberry taste was overtaking the crabapples, but once it was cooked it was fine.
From what I have read, the main thing when making jellies is not to disturb them in any way once you strain them - if you try to hurry or stir the straining process you end up with a cloudy end product. Even though this mixture looks cloudy after straining, don't despair, so long as you haven't disturbed the fruit in any way after you have poured it into the bag it will be fine. I have purchased a jelly bag that hooks onto the rim of one of my big mixing bowls, which makes this whole part of the procedure a breeze.
I leave it totally alone overnight to strain then finish off next day. Make sure you skim off any scum that may accumulate on the surface of the jelly before bottling.
This ends up a gorgeous red colour (hold it up to a window when you've finished - it looks great back lit).