Digital Camera Astrophotography
Wide Field Astrophotography

A simple test for pixel size

Place your digital camera on a tripod or sturdy surface. Use only the widest zoom setting, highest uninterpolated resolution, and no additional lens or adapters. Shoot three (3) photos of the longest exposure possible of Orion's Belt using either the timer function or a remote shutter release.

Do not resize or otherwise alter the photograph so that it maintains the EXIF data, original size, and pixel configuration. Record the shutter speed and focal length of each photo which should all be the same. Open the photograph in a program such as Photoshop or Paint Shop Pro. Locate the star Mintaka in your photograph and draw a select box thru the center of the begining and center of the end of the star trail as below.

Now copy this and paste it to a new image. The size of this new image in pixels is the drift image width and height. Repeat for each photo taken.

Record the details in the table below

Camera Make/Model
Highest Resolution x pixels
Photo 1
Photo 2
Photo 3
Shutter Speed
Focal Length
Drift Image Width
Drift Image Height

You can repeat this test at various focal lengths