Pixelated DCA Logo Digital Camera Astrophotography Formulae
By Gregory Pruden and Markus Ridder

Introduction
In the quest for the perfect image we have created this page to perform many of the formulae important to digital camera astrophotographers. These calculations are based on astrophotography formulae for afocal photography and adapted for use with digital cameras. This page began as an excel spreadsheet and this spreadsheet is still maintained for field use when you are not connected to the internet. We have also been working on confirming these calculations observationally or more precisely photographically and we have a web page dedicated to this task of the project. We welcome your comments and suggestions!
About your Telescope Tip: Hover each box for more info.
Telescope Focal Length: mm (e.g. 500)
Telescope Aperature: mm (e.g.80)
Eyepiece Focal Length: mm (e.g.19)
About your Digital Camera
Camera Focal Length Range:
This is the digital or actual focal length of your camera at the min. zoom and the max. zoom. (e.g 7mm and 70mm) 		Wide Telephoto
mm mm
Camera Focal Lenght of a specific Photo:
(Used for computing exposures)		 mm

Megapixel rating of your camera:

 (e.g. 3.34)
The highest resolution of your camera:
This is the size of a picture with the camera set to fine or the largest non-interpolated pixel count. We need the width and height in pixels. (e.g 2048 and 1536)
Width Height
pixels pixels
In order to compute the effective size of your ccd sensor array we also need one of these three elements of information. If you are unsure enter all that you know. A good source for this information is Digital Photography Review™ or your camera's manual.
Pixel width:
(extreamly accurate) try the simple pixel size test		 microns (e.g. 3.45)
OR
Diagonal size/type of your CCD:
(accurate) 		" (e.g. 1/1.8)
OR
Minimum Focal Length:
(less accurate) 		Actual 35mm Equiv.
mm mm