graticules

[cagey]

hi,
could someone please explain what the graticules on my binoculars are for? also how to use or interpret them, I think they are used for distance off but have no idea how to use them, incidently the bins have compass inside them,
thanks
keith

 

[savageseadog]

Sometimes the instructions are on the inside of the lens caps.
It's possible to derive distance from object of known height/width, or height/width of object from known distance. The graduations will represent for example 10m height at 500m. If you don't know what the graduations represent do an experiment with a chart and work it out.

 

[Poignard]

The instructions for my Compass Binocom 7x50 read:
"Determining the distance.
To be able to determine the distance of an object you need to know its size. Take a bearing on the object...and read off the number of lines on the reticule. Now divide the size by the number of lines multiplied by five. Multiply the result by 1,000 to give you the distance from the object in metres.
Example - Tower has 6 lines on the reticule and a known height of 60m. The distance is: [60/(6 x 5)] x 1,000 = 2,000m."

It goes on to explain how to find the height when you know the distance off but I doubt you will ever need to know that.

Let me know if it works, I've never tried it!

 

[savageseadog]

One thing I forgot was if you are afloat don't forget about the height of the tide when you are considering the height of a land based object. Won't matter of course if it's another yacht or ship.

 

[actionoptics]

What make of binocular? Some have graticles in degrees and others in Mils. If you did not get an instruction leaflet with your bin's, pm me and I'll send you a copy.

 

[pcatterall]

Do some trials using objects when you know the distance to them. This will allow you to build your own table, give you experience in using them and an understanding of the accuracy you can expect.