How to Clean Binocular Lenses Without Scratching Them
Bramwell Views
Most scratches on binocular lenses are not caused by accidents. They are caused by cleaning: a shirt tail or tissue dragged across a lens that still has grit on it. Clean in the right order and your optics will stay clear for years. This takes about two minutes.
What you need
- An air blower
- A soft brush
- A lens pen or a clean microfibre cloth
- Lens cleaning fluid made for coated optics
Our six-piece lens cleaning kit puts all of that in one pouch: air blower, double-ended lens pen, dusting brush, refillable spray bottle (supplied empty, so fill it with a lens cleaning fluid), microfibre cloth and a drawstring bag.
The five steps
1. Blow the grit off first
Hold the binocular lens-down so loose particles fall away, and use the air blower across each objective and eyepiece. Do not blow with your mouth: you will add moisture and saliva. This step matters most. Grit on a lens is abrasive, and anything you wipe across it will drag it over the coating.
2. Brush away what is left
Use a soft brush with light, flicking strokes from the centre outwards. Use the lens pen's retractable brush on the glass, and the larger dusting brush on barrels, hinges and eyecups, where dust collects and later works its way onto the lenses.
3. Clean the glass
Only now touch the lens. Either:
- Lens pen: use the carbon tip in small, gentle circles, starting in the centre and spiralling outwards. Recap the pen straight away to keep the tip clean.
- Cloth and fluid: put a small amount of fluid on the cloth, never directly on the lens, where it can run into the edge of the lens. Wipe in the same spiral from the centre outwards, then use a dry part of the cloth to finish.
Use no more pressure than you would to wipe your eye.
4. Pay attention to the eyepieces
Eyepieces pick up skin oil, sun cream and eyelashes, which smear the view even when the objectives are clean. Fold the eyecups down to reach the edge of the glass. If you have a rangefinder binocular, clean the laser and receiver windows in the same way, as a smear there can affect readings.
5. Wipe the body
Wipe the armour with a slightly damp cloth, then dry it. Mud left on the hinge and the focus wheel eventually ends up on the lenses.
What not to use
- Clothing, paper tissues and kitchen roll. Paper contains wood fibres, and clothing carries grit.
- Household glass cleaners and solvents. They are not made for optical coatings.
- Your breath on a gritty lens. Condensation from a breath can help lift a smear, but only after the grit is gone.
- Excess fluid. Liquid that runs to the edge of a lens can find its way behind it.
Rain, salt and mud
- Rain spots: let the binocular dry at room temperature, then blow, brush and clean. Wiping wet lenses in the field tends to smear.
- Salt spray from the coast: dried salt is abrasive. Wipe it off gently with a cloth dampened with fresh water, then dry and clean as normal.
- Mud: let it dry, then brush it off. Wet mud smears into the coating.
Storage and fogging
- Store dry. After a wet day, take the binocular out of its case and let both dry separately. A damp binocular sealed in a closed case is the classic setup for fungus to grow on the glass over time.
- Add silica gel sachets to the case or cupboard if your house is damp.
- Outside fogging when you walk from a cold car into a warm house is normal. Leave it to clear on its own rather than wiping.
- Fog, dust or marks inside the binocular cannot be cleaned by you. Do not open it up. Contact the seller or an optics repairer.
How often
Blow and brush whenever you see dust. Do a full clean only when you see smears or marks that affect the view. Over-cleaning is a bigger risk to coatings than a little dust.
A kit for the field
Keep a blower and lens pen with you: the lens cleaning kit fits in a jacket pocket or a harness pack. It suits binoculars, spotting scopes, rangefinders and spectacles. Browse the rest of our accessories.
