There are any number of places to have a meter calibrated with the correct piece of equipment. I can think of Calumet, Quality Meters (?) in Hollywood, California and I believe that even Richard Ritter calibrates light meters.
While we all accept a certain amount of statistical variability in using mechanical or electronic devices (shutters or meters), many times the source of the variability in ones photography can be traced to the old say - The Devil Is In The Details. I pay as much attention as practical to ALL of my very valued LF equipment as it is only as good as the weakest link. That is why I also own a shutter tester and use the X Rite calibration scale for the densitometer.
For those of you that shoot predominantly chromes, I will in a similar vein as to results make a case for flare inside your camera off of any surface (wooden or metal) that is not flat black. Could have as much as 1 stop affect on the outside edges of the results.
Cheers!
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