tairving Loc: Magnolia, Texas USA

Today's Astronomy Picture of the Day (APOD) gives us a bit of photography history in a picture of the moon taken with the collodion wet plate process. https://apod.nasa.gov/apod/astropix.html

The explanation, written by a professional photographer, says that this process was used in the mid 19th century to photograph the moon. The process was repeated last November for the picture in today's post. The process involves spreading the photosensitive chemicals on a plate of glass and requires that the entire process from exposing to developing be completed while still wet. It must be done within 15 minutes and has an ISO of approximately 1.

ELNikkor

Appreciate their efforts to exhibit the ways of the past to show how far we've come. Now, let's see a side-by-side of the same subject, same size moon, but with an i-Phone 12, just for comparison...

lamiaceae Loc: San Luis Obispo County, CA

Interesting historical experiment. The optics were essentially modern. The old process does not seem to have the resolving power of say modern 100-125 ISO film. I've used 8x10 Plus-X and with that and you would practically be able to photograph Neil Armstrongs footprints from the astronomer's back yard.

medphotog Loc: Witness protection land

Which is one reason Timothy O'Sullivan's photos from the west are so remarkable. This image is of his photographic wagon. Think about preparing a glass plate negative, hauling oit up to the camera, making an exposure and making it back to the wagon to process in that 15 minute time frame. Sad part is he lost a number of his glass plate images when transporting them via boat that traveled the rapids.