Used to think the idea of tuning you own precious, all-important-mode-of-personal-expression was VERY SCARY....
But I came around...... Here's why...
1. I like my unisons in PERFECT condition ALL the time
2. I DON'T like what some (not all) tuners do to my piano
3. The advent of really FANTASTIC tuning programs (you got it... computer-tuning... shock... horror!)
4. Not putting the HURT on your piano means... in the first instance... not "flag-polling" the tuning pins..... That's absolutely critical...*it'll wreck that old pinblock!!!....but guess what? Most tuners DO NOT pay much attention to this issue! I'm not even sure that many of them pay much attention to "setting the pin," which means, torquing the pin so that it doesn't rebound-back out of tune in no time flat!
S0???/ What to do????
OK... DON'T try to learn the art of tuning from scratch, unless you've got a LOT of time...
Don't just try using ANY old piano tuning program... there are lots of free ones... but they don't "stretch" accurately.
There's only ONE answer.... it's expensive to start with (initial outlay is), but better (sorry to say) than 99 per cent of the tuners out there... "Verituner": it calculates the precise and proper relation of every note on your particular instrument to every OTHER note. The temperament octave is provided with perfect targets (not inharmonicity constants based on an arbitrary theoretical curve, but ACTUAL constants based on every other note on your piano); and if you have time, you can measure every note on your instrument with this beautiful program and come up with a FANTASTIC tuning for your individual piano.
Now tuning your piano AGAINST the targets provided by the program is another matter. You must have a REALLY good tuning hammer (*I'm partial to the new hammers which jolt the pin, and make flagpolling impossible). And you need to get used to difficult strings that do not (on many instruments) tune up easily.,.. But that's the fun part, in my view.
Here, as elsewhere at this site, is the Hailun 218, tuned by ME!!! using Verituner.... and the unisons have settled a bit... I can do a little better than this .... but still.... pretty phenom!http://www.box.com/s/3886484e13e55c6c1fd6
By way of edit, here's a little Scarlatti, recorded using Beyer Ribbons:http://www.box.com/s/xn3ccd4h78q6sg8y0ccp
Anything by Scarlatti will be revealing of various difficult-to-tune intervals on the piano, because the music really wants a non-standard, non-equal temperament tuning, which I do not use with Verituner. Although it will do them, of course.