Re: Building my first serious pinhole

Hi Jim,

That sounds like a really nice camera. I'm curious, though, why you're
so intent on avoiding vignetting. I guess it's just an aesthetic
choice, but vignetting (to my mind) is one of the big advantages of
pinhole images. In fact, I hate it when I don't get that... Just my
2 cents!

Diana
On Dec 1, 2004, at 9:40 AM, JS2RT@aol.com wrote:

> I have been using my homemade 5x7 pinhole camera for over a year now
> with both film and paper negatives. I have a focal distance of 120 mm
> with a pinhole diameter of .016 inches (.406 mm) for an aperture of
> f/295. I am starting to see falloff at the corners, however it is not
> objectionable and many do not notice it at all. The 35mm equivalent to
> the 120 mm I have is 24mm based on the height of the negative.
>
> I used 1/2 inch (12mm) plywood from a model shop for the body because
> this plywood has 7 layers of wood. The lensboard is 1/4 inch (6mm)
> plywood. The pinhole was made from a soft drink can and was taped to a
> 25mm square piece of matboard. Because of the wide angle view of this
> camera, I had to make the opening in the lens board 25mm in diameter
> to avoid vignetting. All of the joints for the top, bottom, sides, and
> lensboard are rabbeted joints in order to create light traps. The rear
> portion of the top, bottom and left panel are also rabbeted for about
> 38mm to form a ledge for the film holder to rest against. The shutter
> is a sample of countertop material cut to an appropriate shape which
> pivots to cover and uncover the pinhole. The right side panel is
> shorter to create the 30mm opening for the film holder. The back fits
> within the top, bottom and left panels and is held in place with
> screws from the top and bottom. The back has two springs from metal
> picture frames to hold the filmholder up against the ledge. The tripod
> socked in the bottom is a 1/4x20 T-nut which is covered on the inside
> with a scrap of plywood. The interior is painted flat black and the
> exterior is varnished. I drew sighting lines on the top and both
> sides.
>
> Good luck with your camera and I hope you enjoy it as much as I have
> enjoyed this one.
>
> Jim Stewart

_______________________________________________
Post to the list as PLAIN TEXT only - no HTML
pinhole-discussion mailing list
pinhole-discussion@spitbite.org
FAQ at http://spitbite.org/pinhole-discussion/list.html
Received on Wed Dec 1 08:50:38 2004