I think that I want to quantify insects color including UV.
I’m going to using this PTFE seat as a white standard.

高反射PTFEシート (thorlabs.co.jp)

However, I don’t have gray standards.
It is difficult to buy off-the-shelf them (ex. Labsphere etc.) because they are very expensive.
So, I think that using gray PTFE tape.
In this way, is it not suitable to use gray PTFE tape as with white standards?
If it is suitable to use gray PTFE tape, could you tell me the product name that can be use analyzing and its reflectance?

Sorry for my bad English.
Thanks in advance.

using grey PTFE tape as grey standards
jolyon Answered question November 11, 2022