Collimation Of Binoculars.

After a few observations under the night sky I realised that the Falcons were slightly out of collimation horizontally, causing a slight double image.
It's not really noticeable unless you're gazing at bright pinpoints like stars because our eyes are better suited to correcting images under bright light. Hence why ghosts are only seen in dark places.

Fortunately, it's quite simple to correct once you know where the collimating screws actually are! Most manufacturers don't include collimation instructions because they want their product to appear rugged and not a sensitive instrument. Plus, it's useless instructing you to be careful not to drop them when they've already been thrown around by a careless delivery driver! Online sellers really should put a FRAGILE label on optical instruments that they are posting!
Rant over!
Anyway, the fix is fairly simple. All you need is a small screwdriver and to know where the collimating screws are located. This is usually under the rubber hand-grip as in the pic below. There is one screw on each barrel.
Horizontal collimating screw for the right side.

It's then a simple matter of:
1) Mount your binos on a sturdy tripod and aim and focus on a distant object.
2) Look through each eyepiece alternately by blinking each eye. If the image jumps from side to side, your collimation is out. 
It IS possible that the image will jump VERTICALLY too. This is also a collimation fault but the adjustment is done with two different screws and isn't covered here.
3) Defocus the right lens. The object SHOULD appear in the centre of the blurry image. If not, this is another way of diagnosing bad collimation.
4) Refocus the object and locate the collimating screw.
5) Adjust the screw by no more than a TINY AMOUNT in either direction and view the object again. You SHOULD notice that the images are either closer or further apart. 
6) Simply continue making tiny adjustments in the correct direction, viewing after every turn, until you can't see separate images any more!

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