Photography Background Blur / Aperture Considerations
Background Blur Considerations for improved photography
Slower aperture lens on APS-C / Crop vs f/2.8 lens on Full Frame body
During a recent Birds in Flight public presentation (for enthusiast photographers) I was asked by a member of the audience if it it was worth invest in a high-performance Full-Frame body / lens for creating sufficient background - my answer was an emphatic no, and I discussed my planning and demonstrated the planning procedure to the member (and the audience in great detail).
With a fast aperture lens, i.e. the Canon EF 300mm f/2.8L IS II USM super telephoto lens, its much easier to blur the background - and when paired with a Full Frame body its almost effortless (ito panning and the work required for rendering background blur compared to an APS-C / Crop sensor body and / or slower aperture lens).
The end result (ito background blur) may look very similar, but there were much more tracking, pre-focus and panning involved with the first two images. Also – with a crop body and i.e. my 100-500 mm lens I’m more mindful of the distance between subject and background. This should increase the blur-effect even more.
Distance between foreground and background / depth of field for both images are very similar - and captured in the same area in the Milnerton Lagoon, Woodbridge Island, Cape Town.
Due to the the larger sensor of the full frame body I was able to crop the 2nd image to more / less the same dimensions as the 1st image.
The end result (ito background blur) may look very similar, but there were much more tracking, pre-focus and panning involved with the first two images. Also – with a crop body and i.e. my 100-500 mm lens I’m more mindful of the distance between subject and background. This should increase the blur-effect even more.
Distance between foreground and background / depth of field for both images are very similar - and captured in the same area in the Milnerton Lagoon, Woodbridge Island, Cape Town.
Due to the the larger sensor of the full frame body I was able to crop the 2nd image to more / less the same dimensions as the 1st image.
It is unlikely that acceptable birds in flight will be achievable with a large aperture such as i.e. f/2.8 - its is recommended to experiment with f/4 - f/8 (depending on the lens or when using a tele-converter for increasing the focal length of the lens).
Image 1: Pied kingfisher (with AI Servo AF tracking / panning)
- Canon EOS 7D Mark II (APS-C Sensor)
- Canon EF 400mm f/5.6L USM Lens
- M Mode: f/5.6 ISO 640 1/4000s Handheld
- Multi-shot mode: 10 fps
- Autofocus: Large Zone
- Mo Lens IS
Image 2: Little Egret (with AI Servo AF tracking / panning)
- Canon EOS 7D Mark II (APS-C Sensor)
- Canon EF 400mm f/5.6L USM Lens
- M Mode: f/6.3 ISO 640 1/4000s Handheld
- Multi-shot mode: 10 fps
- Autofocus: Large Zone
- No Lens IS
Image 2: Swift Tern (with limited AI Servo AF tracking / panning)
- Canon EOS 6D (Full Frams Sensor(
- Canon EF 300mm f/2.8L IS II USM lens
- M Mode: f/4 ISO 500 / 1/4000s handheld
- Multi-shot mode: 4.5 fps
- Autofocus: Single Point
(Click to Enlarge)
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Image 1 : Canon EOS 7D Mark II / 400mm f/5.6 Lens @ f/6.3 |
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Image 2 : Canon EOS 6D / 300mm f/2.8 Lens @ f/4 |
Starting out with Birds in Flight Photography Cape Town View View
Canon EOS 7D Mark II - Birds in Flight Photography Gallery View
Canon EOS Setup and Tips For Birds in Flight Photography View
Canon Photography Training Milnerton Woodbridge Island | Kirstenbosch Cape Town | Around the Cape Peninsula