|Carl V. Hartman and the Costa Rica Collections
How to Take Glass Plate Photos
Follow along as the
glass plate photographic process is demonstrated on a modern version of
Glass plates are placed in plate holders (light-tight
containers) to prepare them for use. The transfer of these plates
into their holders requires complete darkness. Hartman would have
been forced either to do this in a dark tent, or wait until nightfall.
After the camera is attached to a tripod, the lens
is opened and...
...the camera is focused on the object or scene
to be photographed.
Keep in mind, the 'focused' image that is seen through
the lens is actually upside-down and reversed!
The lens is closed and the glass plate holder is
carefully inserted into the camera.
The dark slide (a light-tight sheet in the plate
holder that covers the glass plate before exposure) is removed and...
...the lens is opened to expose the glass plate
to light. Once the glass plate is sufficiently exposed, the dark
slide is returned to the plate holder (flipped to identify the plate
The glass plate holder (with exposed plate inside)
is removed from the camera and is ready for development at any time.
This was repeated for EACH glass plate negative.
Such an involved procedure left many opportunities for error:
- Glass plates were frequently loaded backwards into the camera, with
the emulsion side facing away from the lens (resulting in an inverted
image when the photograph was printed).
- The lens was not closed before loading the plate (resulting in an
- The plate holders were not properly marked after exposure and would
consequently be re-used (resulting in a double exposure).
Special thanks to Jim Burke
at the Photographic & Electronic Imaging
Services, University of Pittsburgh.