How to carry GoPro Hero 13 ND filters on a bike without fingerprints

The Hero 13 finally has swappable lenses, which means most riders now carry loose glass in a hip pack. That is where the trouble starts. Here is how to carry GoPro Hero 13 ND filters without smearing them, and which strength is worth reaching for.

Why loose lenses get dirty

A lens in a pocket meets keys, energy bar wrappers, trail dust and the inside of a jacket. Even in its own soft pouch it rolls, and the moment you take it out, the only way to hold it is by the edges, in gloves, on the side of a trail, in the wind. It never quite works. You touch the glass, you wipe it on a jersey, and you find the smear at home in the footage, where nothing can be done about it.

The scratches are worse. A lens with fine scratches flares in every backlit shot, and unlike a fingerprint it does not clean off.

The box to camera swap

The fix is to stop handling the lens at all and handle a box instead. The lens sits in a shaped box, held on its rim, glass untouched. To fit it, you press the box onto the camera mount, twist, and lift the box away. To take the lens off, you do the reverse: press the empty box on, twist, lift, and the lens comes away inside it. Your fingers only ever touch plastic.

The boxes stack and lock together, so a full set travels as one small block instead of four things rattling around, and each one is marked with its ND strength. That is the idea behind the GoPro Hero 13 lens cover set: a snap-on cover that protects the lens on the camera, plus stacking boxes for ND 4, 8, 16 and 32. Black or white to match the camera.

Which ND for which light

An ND filter is a grey filter. It cuts light without changing colour, so the camera has to hold the shutter open longer. On a bike that is the point: a longer shutter blurs the ground and the passing trees slightly, and the footage stops looking like a sequence of stills.

ND4 is the light one, around two stops. It is the overcast filter: bright grey sky, flat light, no hard shadows. On a dull day the camera is close to the right shutter already, and ND4 nudges it into place without darkening the image more than you want.

ND8 is the everyday one, around three stops. Mixed cloud, sun in and out, and the general purpose choice when you cannot be bothered to think about it. If you ride with one filter in the camera and the others in the pack, this is usually the one in the camera.

ND16 is around four stops and belongs in bright sun. Open trail, hard midday light, a climb without tree cover. In that light an unfiltered camera picks a very fast shutter, and fast shutters are what make handlebar footage look jittery. ND16 is also the one to try in the forest on a bright day, where the light is genuinely strong even when the trail is in shade.

ND32 is around five stops, for the brightest conditions and for the times you want obvious motion blur: snow, open water, a white gravel road at noon, or a high frame rate that needs a fast shutter fed with more light. It is too dark for a shaded forest, which is exactly why you carry the other three.

None of this is a rule. It is the starting point, and the reason to have all four with you rather than at home.

Fit

The set is for the Hero 13 Black lens mount and the GoPro ND lenses in 4, 8, 16 and 32. The Hero 12 and older cameras use a different mount, so this is not a near miss for them, it is a different part. The cover snaps over the lens whether the standard lens or an ND is mounted. Fit notes for everything we make are on the fit guide.

The set is made in our workshop in Bratislava and ships flat rate, 7.90 EUR across the EU, one rate per parcel. The rates are on the shipping page.