Enter the object distance (in) and the focal length (in) into the Image Distance Calculator. The calculator will evaluate and display the Image Distance.

## Image Distance Formula

The following formula is used to calculate the Image Distance.

1/Di = 1/F – 1/O

• Where Di is the Image Distance (in)
• F is the object distance (in)
• O is the focal length (in)

## How to Calculate Image Distance?

The following example problems outline how to calculate Image Distance.

Example Problem #1:

1. First, determine the object distance (in).
• The object distance (in) is given as: 4.
2. Next, determine the focal length (in).
• The focal length (in) is provided as: 2.
3. Finally, calculate the Image Distance using the equation above:

1/Di = 1/F – 1/O

The values given above are inserted into the equation below and the solution is calculated:

1/Di = 1/2 – 1/4 = 4 (in)

Example Problem #2:

For this problem, the variables needed are provided below:

object distance (in) = 6

focal length (in) = 2

This example problem is a test of your knowledge on the subject. Use the calculator above to check your answer.

1/Di = 1/F – 1/O = ?