Instax Mini 99 Filter Adapter

I have always wanted to take long exposure photos during the daytime with instant film but it's always been super awkward trying to hold an ND filter up to the camera without shaking or bumping it and causing an issue with the final result so I decided to design an adapter for a variable ND filter I already had. This adapter is designed to fit a K&F Concept ND2-400 77mm thread Variable ND Filter (note to anyone who wants to print this: the THREADING on the filter is 77mm but that is NOT the diameter of the filter, the ACTUAL DIAMETER of the filter is 85mm) however I could imagine this filter adapter would work just fine with a plethora of filters as long as they can fit within its confines. The filter adapter is designed with teeth to hold the filter in place so it doesn't fall out when pointed downward or shaken and it fits snuggly on the Instax Mini 99 by friction fit. The friction fit on this adapter is solid, I spent a whole day going back and forth across the river taking pictures and it stood up to the test (even when aiming directly down at the water). I should state that even though the filter adapter did stay on my camera snuggly and never came off on it's own I was still cautious when aiming the camera straight down  “just in case”. You should always be careful with your equipment whenever using it in a precarious situation whether it's this 3D print or anything else, I do not take responsibility if something happens to your equipment, your actions are your own. That being said I've never had an issue and it's produced some wonderful images, if you like taking landscape shots of water or even busy streets during the day this will produce some very fun results.

To know if your filter will fit, here are the inner dimensions of the adapter. If your filter is bigger than these dimensions it will not fit.

Diameter: 85.5mm

Depth: 10.5mm