Using Auto ISO for High Speed Action

I'm currently researching the application of Auto ISO in Birds in Flight photography and would like to share a few images captured with the Canon EOS 70D / EF 70-300mm f/4-5.6L IS USM Lens - demonstrating the modern DSLR's ability for making ISO changes (when Auto-ISO is enabled).

Note: My own field study is based on the relationship between BIF photography (high shutter speed action shooting / continuous AF tracking) and the modern DSLR's Auto-ISO function and will not (necessarily) apply for static subjects (i.e. perched birds) - although, I use the same settings when shooting perched birds (when out doing Birds in Flight photography in good light).

The Canon EOS 70D (APS-C / crop body) is not really recognized as a Canon-recommended high-end body (in the same way as the EOS 7D Mark II (2014) and higher were at the time of Canon's 2013 Auto-ISO publication) for shooting Auto-ISO in Manual and the Semi-Auto Modes (Av = Aperture Priority / Tv = Shutter Priority Modes).

Nevertheless, I went out with the EOS 70D on Auto-ISO for testing / demonstrating the typical enthusiast camera's ability for auto-adjusting ISO's in a low-light and fast-changing background shooting environment.

Each of the 4 consecutive frames exposed at different ISO's as the small / erratic bird moved quickly against a lighter to a darker background:

Image 1 ISO 1000
Image 2 ISO 1600
Image 3 ISO 2000
Image 4 ISO 2500

Canon Gear

• Canon EOS 70D
• Canon EF 70-300mm f/4-5.6L IS USM Lens

Exposure Settings

• Manual Mode
• Aperture: f/5.6
• ISO: Auto ISO (1000 - 2500)
• Shutter Speed:1/5000s

Autofocus (AF) Settings

• AI Servo
• Continuous Shooting: 7 fps
• Zone Selection
• Handheld

Focal Length: 300mm

Lightroom 6 Post-Processing
Minimal post-processing (+- 50% crop / slight exposure correction / lens profile correction)

Cape Town Location

Pied Kingfisher at the Pump Station Diep River / Woodbridge Island

Shooting Conditions
Low-light / overcast conditions

Finding

A significant finding is the rapid change in ISO 1000 to 2500 (between the 4 continuous frames) as the camera is attempting an ideal exposure.

(Click to Enlarge)

Image 1: ISO 1000 - Auto-ISO for Birds in Flight Photography (Canon EOS 70D)

Image: ISO 1600 - Auto-ISO for Birds in Flight Photography (Canon EOS 70D)

Image 3: ISO 2000 - Auto-ISO for Birds in Flight Photography (Canon EOS 70D)

Image 4: ISO 2500 - Auto-ISO for Birds in Flight Photography (canon EOS 70D)

Low Light / High ISO Shooting Canon EOS 7D Mark II Cape Town View

Birds in Flight Photography Cape Town View