Exposure, reciprocity and bad luck.

[Grandpa Ron]

I wanted to switch from 35 mm to my 4"x 5" view camera so I would not have to enlarge my negatives to view them. The restoration and use of a 1910 camera takes a lot of time and patients. The negative image is 3 1/2 inches in diameter.

My latest attempts were with a .014" (.36 mm) pinhole and a focal length of 5" (127mm), for an aperture of f 357. To determine the approximate exposer I use a light meter at f 16. It turns out that f 357 is 9 full f stops from f 16. So, if you double the exposure time for every full f stop; you have a time multiplier of 512.

The light meter reading for the photos attached was 1/20 sec. @ f 16 which is about 25 seconds for an f 357 aperture. From past experience I increased it to 40 sec. The film was Arista 100 ISO with standard D-76 black and white development.

I have scanned the negative and one of the positives without post processing the second image has been adjusted for exposure. One photo is my side yard the side the other is my yard swing that I use as a standard model.

And the bad luck, you will notice the top third of the photo was blocked by the shutter not opening all the way.

I hope this information helps those start out.

 

[mcfitz]

Thank you for sharing this, could we see what the camera itself looks like? When converting the old camera, were you able to save the shutter release on it, hence the problem with the shutter not opening all the way?

In some of these images, the blocked part adds to the scene, in others, not so much. At any rate, well done.

 

[narsuitus]

Some time ago, I switched from 35mm to 4x5 inch pinhole images. To avoid the problems I was having with mechanical shutters, I stopped using them. I use gaffer's tape to cover my pinhole and simply remove it when I want to expose the film.

 

[Grandpa Ron]

The shutter came from a toy camera, I cut it out and places it on a camera lens board and made a mount for the remote release. The error was an wayward piece of tape I forgot to remove when tinkering with the shutter.

Another thing I wanted to point out with the f 357 pinhole was the depth of field. I have posted another photo from this batch, the camera to bird house distance was 7 feet the trailer in the back ground is about 125 ft. give or take a few feet.

The camera was a stripped down camera body I inherited from my uncle. Fortunately the bellow were in good shape. A bit of dusting, cleaning and polishing coupled with an old Polaroid lens and I was ready to go. The lenses mount to a lens board for easy changing. Shown are the camera body, a 165 mm lens, the 127 mm Polaroid lens and the pinhole lens. The pinhole lens is .014" diameter made from a Pepsi can sanded from both side to a thickness of about .0025".

I have a 1915 camera lens but I cannot get the shutter to work reliably. Taking one of these apart is defiantly a leap of faith. Also keep in mind that when you switch from a pinhole lens to a large focal length lens your depth of field really shrinks. But that is a topic for another day.

 

[RalphLambrecht]

Thank you for sharing this, could we see what the camera itself looks like? When converting the old camera, were you able to save the shutter release on it, hence the problem with the shutter not opening all the way?

In some of these images, the blocked part adds to the scene, in others, not so much. At any rate, well done.

+1

 

[Grandpa Ron]

Ralph,

Wrestling with this view camera has been quite a challenge.

As you can see in my April post I have three lenses for this camera. I actually have a fourth, a 1915 model but the shutter goes not work consistently. I have had it apart several times (not for the faint of heart) but the shutter is still intermittent.

I have attached a close-up of my pinhole lens, it as a spring return and was cut out of a toy camera. The photo shows the pinhole lens with a .013" pinhole. The white sheet of paper on the camera denotes the distance from the lens to the ground glass film plane so I can calculate the f number for a given bellows distance. The release cable is the weak link, it has just barely enough throw to completely open the shutter. The 6x viewer is used to focus the image on the frosted glass when using a glass lens.

There are several potential problem with a view camera, and I have had many of them but the challenge is too great to ignore.

Good luck

 

[John Koehrer]

In days of old there were releases with long throws. Around 1" they haven't been around for years. Ebay may have one or two show up
but the odds on finding someone that knows what it is are slim.
Could you put a pad on top of the place where the CR contacts the release effectively pushing the release lever further.