How to keep collapsible natural rubber lens hoods in good condition?

[Alan Klein]

Talcum powder

Same issue as with liquids. Powder gets on your hands and then on lenses, film, etc.

[phdgent]

Wouldn't oil, or other solution treatment of the rubber, rub off on your hands and possibly onto film and lenses? Seems risky.

No, this is not going to happen with Ballistol, at all!

As I said, it dries, somewhat evaporates actually, without leaving a residue on the surface, and it penetrates in somme material's suface structure, it only takes a night to do so.
That's why I insisted on Ballistol, and not on any other product.

Just add it sparingly, don't pour or spray it directly, just use a pice of paper towel or a cotton tip to apply it, in some situations I used a syringe, wipe of eventual leftovers and gently rub to dry it with a cloth.
This oil does not gum up neither.

If your hands (or optics) are getting greasy, or sticky, when manipulating that treated thing afterwards, then you might have overdone it.

The only bad side, to some people anyway, is the penetrating turpentine like smell, it's like you are walking in a Northern coniferous forest where trees were freshly felled...

If you try it, you would experience it...

PS: you can apply it directly, with a soaked cloth or by spraying, when cleaning a pice of gear, as for solving old and hardened grease, or dirt caused by using it in a soiled environment (the industry in my case).
Then simply polish by rubbing it afterwards and it will be shiny clean again (and protected).

Don't worry, I am not affiliated to Ballistol, just some 35 years of experience, and I am not a shooter/hunter.

"If you take care of your gear, it will take care of you"