All ready for a great day on the marsh and began getting weird focusing issues with D500 and 500mm pf ......have plenty of batteries, sd cards , lens wipes , extra lens etc....switched out ...no help...focus issues....then I thought ......what if the contacts are dirty....trudged back to the truck and sure enough had 99% alcohol and micro wipe cleaned the contacts on both camera and lens and eureka focus perfect.....I will now clean my contacts before every shoot .......and carry the other 1% with me
