Roll 20: New Life for LF Pinhole

Film: Fujifilm Neopan Acros 100

Camera: The PINH5AD 4×5 3D printed pinhole  f/225  with 6X8 Graflex 120 film Press Back

I have learned a few things since I built this camera, including how to make a better pinhole.  I made a new 0.40mm pinhole for this LF camera before I took it for a field trip.  As much as I love large format, I am not set up to handle it and a Graflex press back was a welcome find.  Of course, the frame is a fraction of the original 4×5 format, but the convenience of 120 film over sheet film is delightful.  I recently bought a Horseman equivalent to play with also.  Expect some LF pinhole experimentation soon.

These shots came out a bit muddy. I blame the very bright ambient light necessitating fast shutter speeds. There were a few indexing issues too.

Road Ivory

Road Ivory

Green Bollard

Green Bollard

The Beach at Carkeek

The Beach at Carkeek

The Beach at Carkeek

The Beach at Carkeek

Concrete Blocks

Concrete Blocks

Concrete Blocks

Concrete Blocks

Flowers at the lake

Flowers at the lake

These rolls were processed and scanned by Moon Photo in Seattle; all images are as scanned without alteration.  More photos from this and my other 52Rolls can be found HERE.

4 thoughts on “Roll 20: New Life for LF Pinhole

  1. Schlem I am constantly impressed with how well your pinhole cameras work. Is a large part of the sharpness the precision of your pinholes?

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  2. Haha – thanks for the kind words.

    There are folks that believe that a pinhole must be flawlessly round for good imaging. I’m not one of them. I can’t bring myself to pay what they ask for a laser-drilled pinhole. So, being lazy and cheap, I make ’em with a calibrated needle awl in 0.001 inch-thick (0.0254 mm) brass shim stock. Knowing the diameter of the needle, I can carefully use it to make a round-as-possible pinhole. I check the diameter with an electronic microscope to 0.02mm.

    But I am only really interested in roundness as a means for accurately knowing the pinhole diameter so as to accurately know my F-number and thus make accurate exposures. If I could make an equally precise square pinhole, I think it would work just as well. But a square aperture is vastly harder to make than a round one. For “sharpness”, I think eliminating camera/shutter motion is much more important.

    Figuring out how to make “quick” pinhole exposures without jostling your camera will serve you well if you want to minimize blur. Having said that, I find many of my favorite pinhole photos by other photographers were hand-held or moving exposures.

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    • Thanks schlem, interesting to have your opinion on the pinhole.

      I used an insect pin (they come in known and precise diameters) in a pin-vice with that same shim stock supported underneath by a beer mat (what else!) for the puncture and followed with very light sanding with 1500 grit sand paper. Mine ended up a bit oval (from the sanding?). I used an average of the widest and narrowest diameters to calculate f-stop – not exact, but probably only making a difference of a fraction of an f-stop anyway.

      I measured mine by scanning and then counting pixels which works OK, except the edges at pixel level are not all that clear. I should just try to make another pinhole and slot it in to see if it makes a difference.

      My pinhole camera only operates with a simple shutter and cable release (a recessed slot for the cable release is the only access to the shutter), but the camera has a long lightweight plastic body (it is adapted from a Polaroid microscope attachment) that has a lot of windage so maybe I am getting camera motion from that. And then there is the instant film which is not all that sharp to begin with, and that might be a lot of the difference.

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  3. ehpem-
    That is essentially how I make my pinholes, but I use 400 grit. Occasionally, I see little dangling bits of schmutz in the pinhole. If I can’t clean it up with some more gentle sanding, I shitcan it. Maybe I’ll try sandpaper with more gritz. Someone gave me a slide projector which I want to repurpose purely for measuring pinholes. I need to 3D print a pinhole carrier that will fit in the projector and allow for even greater accuracy. Lately, I have really been happy with color pinhole over B&W.

    Could you cover the pinhole with a finger, open it with the remote, allow the camera to settle down before smoothly move your finger and then use the remote to close the shutter? I’ve been playing with this technique for shots ❤ seconds, and I think it is an improvement.

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