Air Photo Indices & Film Rolls

Air photo indices, or index maps, graphically represent where aerial photographs were taken relative to their geographical location. With indices, users are able to ascertain the film roll and frame numbers required to cover an area of interest.

How it Works

Flight lines, representing the pattern that the aircraft has flown, are superimposed over the base of an index map. Located along the flight lines are the photo centres of each photograph, labelled with the film roll name.

Typically, the photo centre of the first and last photo in a film roll, and every tenth photo in between, are shown as circles labelled with the frame number. The frame numbers of air photos that are not specifically shown as circles must be estimated along the flight line.

Indices

Download digital indices for air photo coverage from 2008 to 2009:

• Digital Air Photo Indices FTP

Download historical hardcopy block coverage indices for air photo coverage prior to 1963:

• Historical Air Photo Indices FTP

View flight indices for air photo coverage from as far back as 1936:

• Historical Air Photo Index Map Viewer
• Web Imagery Search Interface

Learn more about accessing and using historical air photo indices:

• Historical Air Photo Indices for B.C. (PDF)

Photo Centres

Air photo contractors are required to submit GPS-referenced photo centre coordinates (latitude, longitude, elevation) as a digital, ASCII format file. Photo centres from prior to 1993 are not GPS-referenced.

Download photo centre files, organized by year and operation number:

• Photo Centre FTP

Use the README-NEW file to learn about the record layout.

Film Roll Numbers

In British Columbia, each air photo is assigned with a unique identification number made up of two parts:

• The film roll number (e.g. "BC82012")
• The frame number (e.g. "115")

Prefixes for black and white film rolls are either "BC" or "BCB." Prefixes for colour rolls are "BCC." Prefixes for digital rolls are "BCD."

For photos taken since 1977 (black and white) or 1990 (colour), the film roll number has ten characters with a three-digit extension.

Interpreting Film Roll Numbers

Digit	Description	Example
1–2	Camera focal length code, for example: 88 mm = 88 153 mm = 15 305 mm = 30	30BCC03045 - 105
3–4	Always "BC"	30BCC03045 - 105
5	Film type: B = B&W C = Colour D = Digital (since 2006)	30BCC03045 - 105
6–7	Last two digits of the year of photography, for example: 1988 = 88 1995 = 95 2003 = 03	30BCC03045 - 105
8–10	Sequential film roll number	30BCC03045 - 105
11–13	Frame number	30BCC03045 - 105

Find out the year when a non-digital film roll was taken:

• Correlation of Film Roll Number to Year Taken (PDF)

Camera Calibration

Camera calibration reports are currently available for roll numbers up to the year 2003. Files are in TIF or PDF format.

Download camera calibration reports, organized by lens number and year:

• Camera Calibration FTP

Locate the roll and frame number range in the Cam_cal_lookup file to find the lens number.