Your Browser is OutdatedWhat kind of range do you have in total darkness with a scope like this ? — 2 Answers
The actual amount of light does not affect range as much as things like rain and actual temperature will affect it. It is hard to provide exact ranges, but you should be detecting heat signatures out past 500 yards with this optic. The range to actually identify what the heat signature is will be less.
The darkness, as the other answer states, has no effect on clarity and effective identification range. The clarity of the image will be impacted by environmental factors such as ambient temperature and humidity. Identifying positively that a cow is a cow @ 500 yards is easy if it's standing up. With a little experience, identifying deer (laying or standing) @ that range is also easy. This type of device has no direct comparison to "night vision" (infrared light) devices which require light in the correct infrared range (wavelength) to function, light which comes from the moon or an illuminator.