Endless. Suggest you watch one or two of the great videos Michael Fremer has on this, free on YouTube.
As for me, having tried a few and studied a lot more, the only ones truly "essential" are the stylus tracking force gauge and whatever overhang/alignment jig you prefer. These can be downloaded and printed out for free. But if free rubs you the wrong way then the one I recommend is the Mobile Fidelity Geo-Disk. This has the advantage of being the same thickness as a record. You could of course simply lay the paper printout on top of an LP, same difference.
A lot of guys will freak, but you can get just as good results with $20 worth of the Shure stylus force gauge and a sheet of paper. This is coming from a guy with a Koetsu mounted on a Conqueror on a roughly $20k front end. Images like nobody's business. Done it both ways, love the Geo-Disk for its simplicity.
As for eye strain, any dime store magnifying glass will take care of that. Not that its needed. Believe me, that last little fraction of a millimeter, that's not where its at. So probably most essential of all is a sense of proportion.
As for me, having tried a few and studied a lot more, the only ones truly "essential" are the stylus tracking force gauge and whatever overhang/alignment jig you prefer. These can be downloaded and printed out for free. But if free rubs you the wrong way then the one I recommend is the Mobile Fidelity Geo-Disk. This has the advantage of being the same thickness as a record. You could of course simply lay the paper printout on top of an LP, same difference.
A lot of guys will freak, but you can get just as good results with $20 worth of the Shure stylus force gauge and a sheet of paper. This is coming from a guy with a Koetsu mounted on a Conqueror on a roughly $20k front end. Images like nobody's business. Done it both ways, love the Geo-Disk for its simplicity.
As for eye strain, any dime store magnifying glass will take care of that. Not that its needed. Believe me, that last little fraction of a millimeter, that's not where its at. So probably most essential of all is a sense of proportion.