How to check field of view ? (1 Viewer)

Could someone please explain the simplest way to accurately measure a binoculars field of view.
Can the fov be measured and marked on a wall at 10 yards and then just multiply that figure times 100 to determine the 1000yd fov ?

thank you

One accurate way is to point the binoculars up at the night sky (on a clear night...) and place two stars at opposite edges of the field. Ideally you'll want to put the binoculars on a tripod, if possible. This method is for the astronomically inclined. The hard part is identifying those two stars on a star chart and measuring, on the chart, the angular distance between the two. If you can do that, then you have the true field in degrees. Multiply that figure times approx. 52.5 and you get the field in feet at 1000 yards.

Hint: the distance between the Big Dipper's pointer stars is about 5 degrees.

Thank you for the interesting method.....
but I am not "astronomically inclined".
Can anyone suggest a more 'down to earth' method?

If you are in a store and have a pair you know to compare, look at some wall panels or similar objects and count them. I used to compare mine on a garage door across the street that had a pattern.

Out in the woods, I measure tree to tree with a known pair.

Tero said:

If you are in a store and have a pair you know to compare, look at some wall panels or similar objects and count them. I used to compare mine on a garage door across the street that had a pattern.

Out in the woods, I measure tree to tree with a known pair.

Click to expand...

I use the shingles on my neighbors roof.
Bob

drukja said:

Could someone please explain the simplest way to accurately measure a binoculars field of view.
Can the fov be measured and marked on a wall at 10 yards and then just multiply that figure times 100 to determine the 1000yd fov ?

thank you

Click to expand...

No it cannot.

Close focusing changes both the power and the extent of the fovv in binoculars. For a typical 8x40 or 10x50, you might see only 80% to 90% of the field of view when focused at 20 feet. It grows wider as you look further away. When focused at close distance, some binoculars fov will be only 75% of the max.

If you want to use a close view, you might be better off to look out to about 150-200 feet. Two pencils stuck in the ground and a tape measure would be all that is needed.

edz