Astrophotography Calculator

This calculator computes exposure time and image size based upon your photographic setup and the astronomical object. You may enter notes for each calculation that will be associated with the entered and computed information, all of which can be added to a list that can be viewed and printed. A small database of astronomical objects and their photographic properties is provided from which you may make a selection (or ignore it and enter the object size and brightness values manually).

Prime focus, eyepiece projection, and camera lens configurations are supported, and the calculator switches to the correct mode depending upon your input. You must use the same unit of measurement (such as millimeters) for all dimensional fields.

The object brightness and object size fields each have a second optional field. The two fields can be used to specify a low/high ranges.


Primary diameter or Fstop Primary FL
Film's ASA value Adapter length
Eyepiece FL
Object brightness Object brightness
Object size in arc-seconds Object size in arc-seconds
Notes:
Results
Notes:
Film Speed:
 Eyepiece FL:
 Adapter Length:
Exposure (mm:ss):
 Object Size on Film (mm):
 Working FR:
Primary Diameter:
 Primary FL:
 Primary FR:
Saved to List
List Title

Check the astrophoto notes for additional information

Based upon Astrophotography by Barry Gordon, Second Edition, 1985, Willmann-Bell, Inc. (ISBN 0-943396-07-7).