Hide zero f / F values (e.g. when using a manual lens)

        self, f_num, exposure, focal_length, focal_length35, crop_factor, iso

    ):

        entries = list()

        if f_num is not None:

        if f_num is not None and float(f_num) > 0:

            self.f_num = f"""<span class="fnumber">f/{format_f(f_num)}</span>"""

            entries.append(self.f_num)

                )

            entries.append(self.exposure)

        if focal_length is not None:

        if focal_length is not None and float(focal_length) > 0:

            entry = f"{format_f(focal_length)}mm"

            if focal_length35 is not None and focal_length35 != focal_length:

                entry += f" (≙ {format_f(focal_length35)}mm)"

            location_cache[latlon][str(args.nominatim_zoom)] = location

        except TypeError as e:

            location = latlon

        except Exception as e:

            print(e)

            return

        self.gps = GPSData(lat, lon, location)

        self.html.set_gps(self.gps)

        try:

            lens = self.exif_tag["EXIF LensModel"]

            if lens:

            if lens and str(lens):

                model += f" + {lens}"

        except KeyError:

            # Unknown or built-in lens