An Exposure Time Calculation Table by Zeiss Ikon from Decades Ago
Want to estimate proper exposures without a light meter and don’t mind doing some simple arithmetic? Check out this wonderful Exposure Time Tables pocket reference that was published Zeiss Ikon.
There are 5 steps (i.e. things you need to consider) on the path toward determining your proper exposure time: time of day/year, lighting, object to be exposed, dryplate/film, and aperture. Each step provides you with a number. After the 5 steps, add up all your numbers and then look it up on the chart to figure out your exposure time!
The process was apparently developed by a photographer named Dr. Max Leo. Here are the detailed instructions:
You can find a PDF version of his manual in Michael Butkus Jr.’s online PDF library for camera manuals.
Image credits: Images by Zeiss Ikon AG/OrphanCameras.com