Grandpa Ron
Member
Pinhole cameras haves a natural vignetting feature to them. The exposer looks fine but starts to fade towards the edge of the picture.
Using my 4x5 view camera, I can adjust the bellows to give me an aperture between f180 and f500 with a .016" pinhole. However, I seem that when I get above f250 or f360 I start getting a dark spot forming in the center of the negative.
I am not sure if this is diffraction, or a slight light leak or light reflecting off the bellows interior but it only seems to be an issue with long exposures over 3 minutes or so.
Has any one else noticed this phenomenon with longer exposures.
Using my 4x5 view camera, I can adjust the bellows to give me an aperture between f180 and f500 with a .016" pinhole. However, I seem that when I get above f250 or f360 I start getting a dark spot forming in the center of the negative.
I am not sure if this is diffraction, or a slight light leak or light reflecting off the bellows interior but it only seems to be an issue with long exposures over 3 minutes or so.
Has any one else noticed this phenomenon with longer exposures.