LB476

Thanks. Appreciated all the input, although I was looking for an answer to that specific question, not alternative solutions... Bye bye.

Perhaps you could move the entire thread to the relevant Physics subsection, as the engineers seem to have come up dry...??? Always assuming there is a different audience there... Thank you in advance for your kind attention.

Nope

Problem:- I am decorating my flat with white emulsion and when I come to do the second coat it is hard to see where the first dry coat ends and the second wet coat begins. Using a bright inspection light placed at the right angle it is possible to see a slight contrast between the dry paint and the wet paint. However, this still means you have to keep moving the light source and the observation point to detect this minimal difference... I was thinking if I changed the colour of the light source and wore tinted glasses this could increase the contrast between the coats. This sounds like a physics question to me. Which colour combination would give the greatest contrast...??? For practical reasons the light source needs to be readily available, perhaps Infrared or UV, or just use a tinted glass filter on the white inspection light. Similarly, inspection glasses are produced with grey, black, blue or yellow lenses... Thank you in advance for your input.

Problem:- I am decorating my flat with white emulsion and when I come to do the second coat it is hard to see where the first dry coat ends and the second wet coat begins. Using a bright inspection light placed at the right angle it is possible to see a slight contrast between the dry paint and the wet paint. However, this still means you have to keep moving the light source and the observation point to detect this minimal difference... I was thinking if I changed the colour of the light source and wore tinted glasses this could increase the contrast between the coats. This sounds like a physics question to me. Which colour combination would give the greatest contrast...??? For practical reasons the light source needs to be readily available, perhaps Infrared or UV, or just use a tinted glass filter on the white inspection light. Similarly, inspection glasses are produced with grey, black, blue or yellow lenses... Thank you in advance for your input.