Anything with an ISO-approved number 14 lens will do the job, so might a surface with enough reflectivity to reflect the light but nothing else (think those homemade viewing kits people make out of kleenex boxes), or you can watch it through a rear view camera, the last one being considered most beneficial.
Anything with an ISO-approved number 14 lens will do the job, so might a surface with enough reflectivity to reflect the light but nothing else (think those homemade viewing kits people make out of kleenex boxes), or you can watch it through a rear view camera, the last one being considered most beneficial.