you have a G15 with a zoom, right? The EXIF shows you shot at the widest possible setting. Going a bit higher and zooming in would likely maintain the look of the slice being tall.
Right, 6 mm. EXIF data are where I originally posted; we can't use the metadata feature more than once for an image. Would backing off and zooming make the lens, in effect, longer? I get so much distortion in shots at this distance that everything is unnaturally foreshortened. I discarded all the attempts that included a fork beside the plate. The fork looked huge.
I initially thought there might be a consensus, a standard in the field. Apparently there isn't, except for the vertical angle (namely, go higher).