You can covert your old flashlights by using red cellophane over or under the lens in layers. You can also buy red light kits for most mag lights. There are also numerous red flash lights available on the net at low costs. Wal-Mart carries a Ray-o-vac swivel head AA flashlight that includes a red lens. Craft stores sell red cellophane and gels.
You can still carry a white light flashlight in addition for use in emergencies. Red lens will help save your night vision on investigations, be less distracting to other investigators, draw less attention to us in cemeteries and also eliminate the chances of flashlight caused anomalies in photos.
More how to tips:
a “red flashlight” - a flashlight with a red lens. (If you don’t have one, place red cellophane around your flashlight and secure it with a rubber band , paint the lens in red nail polish or cut a circular piece out of a red plastic report binder and place it under the lens.) It is easier to adapt your eyes to the night sky with this type of light rather than a regular flashlight. Red brake-light tape can also be used.
Where to get red lens flashlights and kits :