Leica, Bosch, Stanley?

[Bob Thrun]

FYI - when accuracy counts, using a decent target for the laser makes a difference. DON'T use anything reflective!

Actually, for maximum range, you should use a retroreflective target, like Scotchlite brand tape. The maximum range I got from a Disto 4 to a yellow survey notebook cover or light-colored rock was about 140 feet. I got 250 feet to a white painted building. It might depend on how fresh the batteries are.

The Stanley Fat Max has its maximum range artificially limited to about 60feet/20meters. Its buttons are simpler than those of the Disto, but they are too easily pressed. Kirk MacGregor built up the area around the buttons so that they were in a shallow well.

[NZcaver]

FYI - when accuracy counts, using a decent target for the laser makes a difference. DON'T use anything reflective!

Actually, for maximum range, you should use a retroreflective target, like Scotchlite brand tape. The maximum range I got from a Disto 4 to a yellow survey notebook cover or light-colored rock was about 140 feet. I got 250 feet to a white painted building. It might depend on how fresh the batteries are.

You're right, I should clarify my comment.

Some new users apparently assume you need a highly reflective surface to bounce the laser off (like those plastic reflector discs you see sometimes). My understanding is this can have the opposite effect, scattering the reflected beam and potentially introducing errors into the reading - at least at "caving" ranges less than say a hundred feet or so.

I mostly use a target made from a folded square of thin white closed cell foam. However, Scotchlite would no doubt be useful for shooting those long borehole shots and deep pits. My Classic 5 supposedly has a max range of 650 feet, but only with the right target and a very steady hand/support.

[Martin Sluka]

So if I were to buy one, which one?

Personally: I'll never buy laser rangefinder without timer (delayed measurement) feature. I have very good reason for it based on many years of using laser rangefinders in caves. Only with timer one may really fix the laser rangefinder with both hands in difficult situation, measuring of long distances, etc.

On other hand laser rangefinders with timer are not in category of your question.

There are only three kinds of natural surfaces in caves the laser rangefinder will not work:
1. water surface
2. totally non-reflective mud
3. flowstone with large crystal faces

In most of cases movement of beam one or two centimeters to find acceptable surface would be enough.

Any high reflective material will NOT works too.

Target: If you want the target which will save you plenty of time in caves and which solves the problem of parallax error on shorter distances check:

http://cachtice.speleo.sk/laser/

Martin