Experiment: Canada Geese at 380 Yards with a Focal Length of 400mm

Canada Geese at Home Lake. 100mm focal length.

After photographing our rare Tundra Swan, I was getting ready to leave Home Lake when I had an opportunity to test the kind of results I could get photographing distant geese with a 100-400mm lens. I was on the dam at Home Lake so I positioned myself so I was in line with the water facility apparatus in the lake and some distant geese. I did a reference photo at 100mm.


Canada Geese at Home Lake. 400mm focal length.

Then I zoomed my tripod mounted lens to 400mm, focused on the distant geese, and did my test photo.

Google Earth Pro, Measuring Tool.

My next step was to determine how far away the geese were. I used the Measuring Tool in Google Earth Pro. I drew a line from my location on the dam to the location of the distant geese. Google Earth Pro gave me a distance of 381.21 yards. However my choice of the location of the distant geese is somewhat approximate. They were in between the first and second bulge of land out into the lake, but my choice of their locations could be off by 10-20 yards. For the purposes of my experiment, the geese were a long way away from my lens, whether it was 360 yards or 400 yards or somewhere in between.

So how did my lens do at 400mm at roughly 380 yards!

Canada Geese at about 380 yards, 400mm lens. Unprocessed image.

This is the center of the image enlarged to 100% “actual pixels” magnification. The image has not been processed in any way. I just opened the file and clicked the magnifying glass until I was at 100%. That means one pixel in the digital image is one pixel on my computer monitor. Then I chose the center of the image to show you. Actually, I was pleasantly surprised. They are soft, but that distance they look better than I expected.

What if I processed the image?

Canada Geese at about 380 yards, 400mm lens. Image. Processed image.

I took the original unprocessed image and did only one thing, I used Topaz Sharpen AI to sharpen the image. You are again looking at the center of the image enlarged to 100% “actual pixels” magnification. Topaz software continues to impress me.

I had a lot going for me. Bright sun and a low camera ISO. Subjects that were moving slowly. Lens/camera mounted on a tripod. And of course a quality Canon L series 100-400mm lens.

Of course I would prefer to be much closer. If I made a print of just these four geese (705×567 pixels) it would be smaller than 2 x 2.5 inches. The lesson in this is you have almost nothing to loose by clicking the shutter, even with a subject over 3 1/2 football fields away. If it doesn’t work, it doesn’t work. But what if it does work? I learned long ago to try photography things that aren’t supposed to work. Sometimes they DO work.