If I touch a plastic surface for 1 second, will it leave a thermographic signature?

Question

I am considering hiring an infra-red camera to check for myself, but it is quite expensive.

Lets assume my index finger is in question, and it is at normal body temperature.

i.e. a discernible trace that could be picked up by appropriate measuring equipment.

I presume that the energy transferred will dissipate very quickly.

If so, I'd also like to know, how fast I'd have to be with my measuring equipment to pick up the trace.

Answer 1

Will you change the temperature of the surface? Yes, as long as the surface is not at the same temp as your body surface.

Whether it leaves a "thermographic signature" or not depends more on the resolution of your measuring equipment than the material. How long you have to catch the signature depends on the temperature, thickness and thermal conductivity of the surface, the temp of your finger and the surrounding air, and the resolution of your device. I have seen demonstrations that show footsteps on a floor fade over a few seconds....

Answer 2

Yes, any physical contact will share energy with the object, and even near contact (hovering over it with your hand) will radiate heat to it.