05-17-2020, 04:56 PM
I was tempted to give a similar advice as toni, but I am slightly biased in this regard 
Generally: if you buy used, either buy from someone near where you can drive and test in person before agreeing on a deal. Or buy from commercial sellers that offer warranty.
To add to Klaus' list: I see Nikon on a similar path as Canon, slightly worse than Canon in the past, but pretty solid nowadays, especially since they are (finally!) moving towards electronically controlled apertures. The mechanical aperture lever occasionally failed on few of my own lenses, plus it is by design less precise than an electronic aperture.
Not on Klaus' list: Tokina. I personally avoid Tokina for many years now, as a result of a notoriously high rate of decentered lenses, combined with the worst service of the industry, at least here in Europe where Tokina service is handled by the distributor (Hapa team).
Regarding your 55-200: I checked all my XF lenses, and yes, they all can be moved a little in each direction, as you described it with your 18-55, but none of mine can be moved easily, for example by zooming. I am apologizing in advanced if that brings your worries back
Also: I don't think you need to worry about unmounting your lens when the camera is on. I am sure the warning you saw during the update shows up to make sure you do not interrupt the update process accidently (which might render the camera useless). The only lenses I know that came with specific instructions for unmounting are the Canon EF 85 L (both versions) and the CAnon EF 50/1.0 L, which should be set to inifinity before unmounting, because otherwise the extended lens tube with lots of heavy glass in it can put a lot of stress on the AF drive, causing the AF to fail at some point (happened to one of my clients once).
Generally: if you buy used, either buy from someone near where you can drive and test in person before agreeing on a deal. Or buy from commercial sellers that offer warranty.To add to Klaus' list: I see Nikon on a similar path as Canon, slightly worse than Canon in the past, but pretty solid nowadays, especially since they are (finally!) moving towards electronically controlled apertures. The mechanical aperture lever occasionally failed on few of my own lenses, plus it is by design less precise than an electronic aperture.
Not on Klaus' list: Tokina. I personally avoid Tokina for many years now, as a result of a notoriously high rate of decentered lenses, combined with the worst service of the industry, at least here in Europe where Tokina service is handled by the distributor (Hapa team).
Regarding your 55-200: I checked all my XF lenses, and yes, they all can be moved a little in each direction, as you described it with your 18-55, but none of mine can be moved easily, for example by zooming. I am apologizing in advanced if that brings your worries back
Also: I don't think you need to worry about unmounting your lens when the camera is on. I am sure the warning you saw during the update shows up to make sure you do not interrupt the update process accidently (which might render the camera useless). The only lenses I know that came with specific instructions for unmounting are the Canon EF 85 L (both versions) and the CAnon EF 50/1.0 L, which should be set to inifinity before unmounting, because otherwise the extended lens tube with lots of heavy glass in it can put a lot of stress on the AF drive, causing the AF to fail at some point (happened to one of my clients once).
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