Shopped Amazon for various labels last night. Today, in a local store called Bi Mart, I found a small package of reflective labels that gave me a head start. Rather than label every lens for focal length, I decided to identify things that confuse me most often. When I shoot from roads in the redwoods, I often have my Tamron 24-70 and 70-200 uncapped and on two bodies. So I marked one more broadly to ID its wide angle. Otherwise the long zoom can't get confused with anything. The other two Tamron, the 35mm and 85mm have interchangeable caps so no need to mark those.
I used orange to identify RF lense caps like the RF 50mm 1.2 and also the rear RF caps including for the EF > RF adapters. I marked yellow on a couple other Canon lens caps mostly to know they don't go on an RF lens.
There are also circular adhesive labels about 1/2 inch wide that could be written on and placed on every lens cap for focal length, but I think this two color label thing fine-tunes deciphering things for me when I have several lenses out, caps off, etc.. If I add a couple more lenses, I may put a 1/2 circle label on each lens cap. I see a good chance of getting the RF 24-105mm and maybe close to a Canon 24mm.
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