The last in this series about binoculars firstly considers Collimation.
If a pair of Binoculars are correctly collimated both barrels are in line and will make it possible for your brain to correctly combine both images into a single view. If Binoculars take a knock they may not be collimated. To check if there’s a problem hold your bins at arms length and look through the wrong end! – see if a straight horizon runs through both barrels or is it ‘stepped’ ie higher in one than in the other. If it is stepped the binoculars will need re-collimating; not a cheap process. Carrying out this test is particularly important if you’re buying second hand binoculars.
I’m often asked how much you should spend on a good pair of bins. It’s possible to spend up to £2000 on a state of the art pair. As a minimum you should be looking at £150 to £200. However I would recommend you buy the most expensive pair you can afford. This will be an investment in something you may keep all your life … or at least until you see a better pair. :0)
Once you have them, look after them. Buy a rubber bulb blower and blow off dust from lenses before lightly brushing with a clean hair brush to remove any larger particles (a blusher application brush is ideal – unused of course!) Then remove grease with a lint free cloth; a lens cloth is usually supplied with your binoculars, taking great care to wipe GENTLY. Don’t damage the coatings on the lenses.
Hopefully you will now be equipped with several things to consider when buying a pair of Binoculars.
Checking Collimation
Letter From Norfolk 