Focal Length Conversion Chart

**Edie** · 12-Aug-1999, 18:32

Is there a focal length conversion chart for 8x10, 4x5, 6x12, 6x9, 6x7 and 35mm formats?

**Robert A. Zeichner** · 12-Aug-1999, 19:45

In the 1999 Photographic Artist's Catalog from Calumet Photographic, there is a chart on page 6 that details the angle of view relative to lens focal lengths. I believe this will help. I understand a Java version of the chart appears on the calumet website. www.calumetphoto.com

**Ellis Vener** · 12-Aug-1999, 20:58

Rounded off , I find these factors work well:

35mm = 1x

6x7cm = 2x

6x9cm = 2.25x

6x12cm = 3x

4x5 = 3x

8x10 = 6x

I based these findings on the similar angle of coverage along the long dimension, not the diagonal.

**Sean Billy Bob Boy yates** · 12-Aug-1999, 23:17

I believe there's one at www.thefstop.com

**Jan erala** · 13-Aug-1999, 05:06

I use this simple calculation: focal length x comp. film measure divided with relevant film measure. E.g what would a 135 lens with 4x5 be in 35 mm format? 135 x 36 : 125 = 38,88 mm It can be used as good for height,widht or diagonal comparisons.