What's the meaning of where Brunette states that the bulbs are halogen - is there some reason a halogen bulb would not work for finding hidden text on the paper?
shareI noticed that too and thought it was a bit odd. Probably a script issue. Something that made sense in the script but got lost when directing/cutting etc.
shareThey had already been viewing their papers under the halogen light, and saw nothing. So it isn't that there is something inherently wrong with halogen lighting, just in there circumstance halogen was the default and had already been tried and tested. She and eventually they felt the need to test the paper under different other kinds of like the incandescent then black light then infrared, because perhaps that was the key to fighting the question on the paper.
shareI want to know what good the safe lights would have done since the paper had already been exposed to white (halogen + fluorescent) light. If it was photo paper, any image exposed on it would have already been ruined.
Invisible ink writings I know (like lemon juice) need a heat source to reveal themselves, like incandescent bulb or the flame in a candle. Halogen light bulbs are known to be much more efficient than incandescent, partly because they emit most of their energy as light, not as heat, like the latter does.
http://www.sciencekids.co.nz/experiments/invisibleink.html
cheers from Chile.
Halogen lights a plenty bright and they also create a lot of heat. You can even buy heaters that are made with halogen lights.
shareYou are incorrect. Halogen lights burn hotter and are able to produce brighter light because of this. They also last longer than a typical incan bulb because the halogen gas binds with free filament molecules and drop back down onto the filament instead of getting dispensed onto the side of the bulb.
If you still disagree about the whole efficiency/heat thing then try touching the bulbs of the two and compare.