Spring Lake, MI. Sponsored Topics. Spring Lake is a village in Ottawa County in the U.S. state of Michigan. The population was 2,514 at the 2000 census. The village is located within Spring Lake Township. After Captain Benjamin Hopkins purchased land here in 1837 and built a mill, the place became known as Hopkins Mill.
All binoculars will have two numbers to designate them, such as 10x50. This means a binocular with 10 times magnification and 50mm objective lenses (the big ones!). Common sizes are 8x42, 10x50, 20x60, 15x70, etc. Optical glass is generally BAK4 or BAK7 standard, BAK4 is denser and gives superior vision.
A plus sign would indicate farsightedness. The second number (-1.00) is the astigmatism. If there is no astigmatism, we generally write the letters DS or SPH after the first number to let the optician know that we didnât just forget to write in the astigmatism. The final number (180) is the direction (AXIS) of the astigmatism.