Depends on the horizontal size of the find and the depth. I determine size by scanning N to S then E to W and mark the extremes with golf tees....
Shrews: on your chronic back pain, a Hang Ups or any similar device will do more than ease pain for a short time. Look at the Hang Ups website....
I had persistent back pain for years that interfered with all activities including detecting (digging). I began using a Hang Ups inversion table...
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