For your damson wine, pectin may well be the problem (as it would possibly have been for your apple wine, but the recipe for that includes pectic enzyme). Damsons are high in pectin - so much so that you can make damson jam or jelly with no added pectin at all. Sometimes, but by no means always, the pectin comes out of solution and forms tiny particles which are held in suspension within the wine - hence the haze. Sometimes, the haze drops out with time. Sometimes it drops out with lowering temeratures. Sometimes it drops out after a couple of years when you'd despaired of it ever clearing. Sometimes it does none of those things and you're left with a hazy wine - but it's perfectly drinkable and does no harm at all. If you're really bothered, you can treat it with a double dose (two level teaspoons per gallon) of pectic enzyme. If you'd included the enzyme at the outset, it would have needed only one level teaspoon per gallon.
The elderberry is different as elderberries are low in pectin. As you say, that haze (which may simply be bits of remaining yeast and fruit debris) will almost certainly drop out given time and may even clear quite soon as long as you keep the wine in a cool place.
You can take a hydrometer reading any time you like, although it doesn't make a deal of difference - your wine is ready or it's not. The hydrometer comes into its own if you're interested in precise measurement of final alcoholic content or if you're attempting to make a sweet wine. As a rough guide, though, 1lb of sugar in 1 gal. of wine gives you all but dammit 5% ABV (so a kilo comes out about 12%) - but you have to take natural sugar content into account as well as added sugar. Sugar content of most fruits can be found using the wonderful Google.
You can look here ...
http://winemaking.jackkeller.net/
... for loads of recipes, but bear in mind that Jack is American - he uses US measurements. But to be perfectly honest (and I can sense someone preening here) I'd recommend Andy's book - Booze for Free - which has all manner of fine recipes (and a few odd ones
). And remember that you can make wine from dried fruit, tinned fruit, cordial, fruit juice, fruit teabags etc. etc.
Yes, you can get your tannin from teabags. A half cup of tea made with one teabag left to go cold with the bag in it (or a full cup made from two teabags) provides enough tannin for most purposes - but check your fruit for tannin content beforehand (Google again). Elderberries, for instance, are massively high in tannin all by themselves. High-tannin wines mature much better than low-tannin ones, but you have to wait that much longer to drink them.
And, no, it's not overly ambitious. If you're going to do it, jump in at the deep end, I say.
Mike
Oh - be prepared to be a bit disappointed with your rowan wine. Some people like it, but I think it's a bit of a waste of time.
Incidentally even those take about a month so maybe it's down to where we are - Liverpool is probably a lot warmer so yours should be quicker.
!
