Is it a legitimate, reliable way to tell if a certain light type or color will affect nighttime behavior by observing pupil dilation when subject to direct light? For example, I have a whitish/light blueish led flash light. If I shine it directly into my two female crested geckos eyes their pupils shrink from covering their entire eye down to a tiny slit down the middle as if it was daytime. However, when I shine it directly into my mossy frogs eyes their pupils do not shrink at all. Is it safe to assume that I can use those bulbs for nighttime viewing of their enclosure without disturbing their nighttime behavior?