How many zones is your standard

[robc]

AA's system goes from Zone 0 to X, for paper balck to paper white. Zone IX, however, is so close to paper white that there is little, if any, difference.

I think the point here is, what do people find their typical subject brightness range to be. From that it follows that Normal development should be tailored to suit that and not some arbitrary number. So if using zone 0 thru X usually requires you use N+ development then it may be useful to zones 0 thru IX or 0 thru VIII as your norm. To say there is such a small difference that its not worth considering, is simply not correct. There is a whole stop difference and more for people standardising on zone VIII for paper base white. I merely asked the question to see what people have standardised on, and of those who have voted, it seems zone IX is prefered.

[Ralph W. Lambrecht]

I don't understand this completly, but maybe it helps to explain what I do, and you can derive my answer from it.

I test film speeds for Zone I.5 (0.17 >b+f) and normal development for Zone VIII.5 (1.37 >b+f). I know that highlight with traces of tonality will go to Zone IX and specular highlights, having no tone whatsoever, will reach Zone X.