Slim filters for Fuji GF670

Fuji GF670 is a great medium format camera, but has a few drawbacks. I’ve been shooting happily with it for a long time but every once in a while I wished I had a filter on. The way you are supposed to use filters with it is quite bonkers. A hood that you attach each time you want to use them, plus you have to take it off every time you want to close the camera? Using it is slow as is… Chances are I’ll shoot all of the 10 frames of a roll using the same filter. I’d like to be able to leave the filter on the camera.

I love high contrast black and white photography, and like using yellow/orage/red filters where appropriate. An ND filter can be nice as well, given that this camera maxes out at 1/500s shutter speed.

Looking at the front of the lens, there’s just a couple of millimeters, maybe 3, of clearance that could be used to fit something. So I started tinkering in FreeCAD…

After a few iterations, the results are pretty self explanatory. A simple 3D model that houses the filter glass and has two compliant arms that “bite” into the existing filter threads.

Printed in PETG with 100% infil, the filter holder is sturdy enough to stay in place even if you handle the camera rather violently. And, of course, it’s thin enough to allow the collapsible lens to fold with no issues.

Model is designed to be printed half way and paused. Then the filter is put in place and printing is resumed. This way, the filter glass is retained without any glue or screws being necessary.

This particular set of filters came from a set that accompanied a mostly useless Minolta 500 reflector lens, but any suitably sized piece of glass would work. The model I shared can be modified in FreeCAD to suit your size requirements and can be adapted to other lenses as well.

Note that light meter on this camera isn’t TTL, so you’ll have to adjust the exposure compensation according to the filter you are using.

Find the model and STL on my github page here: gf670_filter.