Can you ever get perfect alignment?


People are always agonizing about getting perfect cartridge alignment, or at least close to perfect, which is a good thing. But is it really possible? Assuming the diamond is perfectly aligned on the cantilever, which is a big if, the only gauge I have seen that would give near-perfect alignment is the Mint, which enables you to sight the cantilever between two tiny parallel lines. I had to give up on this because it was just too difficult with a cartridge with a small cantilever. At least for me. So the Mint and it’s progeny aside, how can anyone expect to achieve this microscopic level of alignment with any other jig? With the Basis gauge, you line the tonearm up with the lines on the jig. Ok, but you’re telling me that a human being won’t be off by a few thousandths of an inch? Or the Geo-Disc. Point the arrow at the pivot point? Are you kidding? You could probably be off by 1/4" easily. Or the Dennision. Unless there is an indentation at the exact center of the pivot - how can you ever get enough precision to work at the distances we’re talking about? Personally, I did the best I could with the Basis gauge and my setup sounds very good to me. No mistracking or other nasties, so I’m good with it. I’ll tell you one thing - my next cartridge, if I live that long, will have a large, front-mounted cantilever.
chayro
Of course we can't get perfect alignment but we can get it very close.

Usually the best alignment protractors are the ones supplied by the turntable manufacturer because they know how to line up the arcs and null points relative to the tonearm pivot axis.  
I agree about universal gauges that ask you to align to the pivot point by sight-it is introducing the chance for greater error.  
The mint "best tractor" has worked and sounded the best for me and my table (technics) given that the results with the supplied gauge were not optimum.  
In your case trying to align short cantilever (dynavector?)  i would suggest adding some local stationary lighting and magnification (e.g. a 3-piece magnifying optic) to make it easier to see.  
even though we can never get it perfect we can get close and careful setup work does pay dividends in sound quality. 
you'll know when it's right when most of your LPs sound great from outer to inner grooves.  
Of course you can get a perfect alignment. With some carts it is easy (carts with naked cantilever for example) and with others it will need time. Take care that "it" will fit perfectly onto your spindle (they can have different diameters)...
The Graham Phantom Arm for example has a alignment jig and you can do it perfectly even with 10 left thumbs.

So far we have one "of course we can't" and one "of course you can".  
I know we may be able to get a cart perfectly lined up with a gauge, but is the gauge lined up?