On Fri, Oct 10, 2014 at 9:35 AM, Jones Beene <[email protected]> wrote:
Next let’s say the bulb presented is frosted, and you are naïve and do not > know that it contains a hot filament - but I use the camera to focus on an > area of the bulb’s exterior, where from prior experience, I know that the > filament radiates the most photons, even if that reading is diminished in > intensity from a clear bulb … this technique can still result in a 3:1 > over-estimate of the net emissivity of the bulb, since there is a strong > contribution from a hot filament. This can be demonstrated rather easily to > be factual. > This is a helpful analogy. I was wondering why the emissivity of alumina was an issue. I take it this sort of issue is resolved by coating the thing device being measured in a black refractory coating. Eric
