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.
Finderscopes usually come with a designation of the form AxB, where A is the magnification and B is the aperture of the finderscope's objective lens in millimeters; for example, a 6Ã30 finderscope means a finderscope with a 30 mm objective and a magnification of 6Ã. This designation is in the same format used by most binoculars. A 6Ã30 finderscope is the minimum useful size for a finderscope on an amateur telescope, and an 8Ã50 or larger finderscope is preferred.