The #FrugalFilmProject, February 2024 (Part Two): Using Neutral Density Filters with the 1920s Generic Folding Camera

The #FrugalFilmProject, February 2024 (Part Two): Using Neutral Density Filters with the 1920s Generic Folding Camera.

Earlier this month I described how I was using the guides drawn on the ground glass by a previous owner of the 1920s generic folding camera to frame images on Instax Wide film. I observed then that on bright sunny days the camera would not stop down enough so that the images were properly exposed, the film was just too sensitive, and I thought that it would be a good idea to use neutral density filters to cut down the amount of light hitting the film and make exposures more manageable. 

I measured the diameter of the camera lens (28mm) and ordered a 30,5mm to 37mm step-up ring and a couple of cheap 37mm neutral density filters. When the step up ring arrived the inner diameter was still about 1mm too big for the lens, so I wrapped a little light seal felt around the inside of the thread and tried again. This time it fitted perfectly. It was tight enough that I could screw an ND filter onto the step-up ring and yet would not cause any permanent damage. The 37mm filter was also the perfect size that I could still access the aperture and shutter speed dials. But would it work?

I loaded the three film holders with Instax Wide film and headed out. With the camera mounted onto a tripod and using a dark cloth to shelter the ground glass image from the sunlight I exposed two woodland images, one at 1/100s at ISO 800 without any filter and a second at the same exposure but factoring in the change of aperture using the ND4 filter. The third image I exposed in a sunny patch of woodland.

The framing of all of the images was ideal using the guides on the ground glass. Unfortunately, though I could not really show that using the ND filter worked because one of the images was not exposed. I think that I forgot to remove the dark slide before taking the picture (rookie mistake). I've reloaded the film holders with more Instax Wide film, but the weather for the next ten days is forecasting rain and it's going to be difficult to test my theory. 

As an aside, instead of continually squinting and trying to frame the images on the guides on the ground glass, I've taped around the marks on the ground glass screen with black electrical tape. Now, whenever I look through the viewfinder I'll only see an area equivalent to the size of the Instax Wide film. Hopefully this will make framing a little easier. Now I just have to adjust the viewfinder so I can use the camera hand-held. 

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#Generic, #Folder, #Camera, #1920s, #Instax, #Instant, #InstaxWide, #Experimental, #Vintage, #FrugalFilmProject,