Most of us know and some even love pinhole photography. The pictures created using a very tiny hole in a dark box, the long exposure times more in the minutes, even hours, than seconds: The process of pinholing is as magical as fascinating to some and as boring as inconvenient to others.
Some photographers equal pinhole images to blurry pictures. Almost synonyms.
Having that in mind I started to optimize the pinhole concept. Relevant factors like hole size and evenness, negative format and “focal” length were identified constants or variables for perfection in theory. Along that bumpy learning curve some surprising facts showed off being important.
The most irritating and against all common sense is the following: Hole size does not depend on focal length. Period. Instead, these both depend on the dimensions of the negative exposed.
An example might illustrate that: A pinhole camera which delivers good sharpness and even exposed negatives for format 6x6 cm will not deliver excellence for format 8x10 inches when using the same focal length and hole size as for 6x6 cm.
Quite on the contrary, a 8x10 inch pinhole needs different hole size and different focal length to work as close as possible to the optimum. The limitations due to physics are obvious. Nevertheless pinhole photography like any other photography follows the given rules in optics. Those provide solutions which can help in optimizing pinhole imaginary.
The image posted here shows what is in reach. My 8x10 inches pinhole “Core-CO” delivers 95% of the maximum quality when it comes to sharpness, vignetting (even exposure) and distortion. What You see here is the contact print of a paper negative. Exposure time 14 minutes.
Selenium toning did a good job to get deeper into things.
To sum it up, it’s up to you: Create those titanic super-blurry pictures or shoot images which do not show their pinhole origin at first glance. Both and all in between created with one and the same Camera obscura.
In this case the “Core-CO”, one of the lightest 8x10 inches pinholes with bellows on the planet: 1.36 kilos.
Rewarding, fingers crossed.