topic Re: Improve autofocus for birds in EOS DSLR & Mirrorless Cameras

EOS R5 How to improve autofocus for birds

luciano — Sat, 10 Feb 2024 20:31:25 GMT

I have a Canon R5 and took this photograph of a Great (Parus major) this morning in dull conditions. Camera focused roughly on the branch at the red square rather than the bird.

Any autofocus settings I can use that would make it more likely the camera would find the bird in this sort of photo? Does camera have digital zoom to make bird larger in frame so that there are less twigs to distract the autofocus?

[Sorry, but our system won't let the bird's proper name be typed out. We substituted it with its scientific name.]

Re: Improve autofocus for birds

Tronhard — Sat, 10 Feb 2024 19:19:13 GMT

Hi and welcome to the forum:
My first question would be what autofocus method are you using? If you are using the default setting, the camera will tend to focus on the nearest object with sufficient contrast, which was probably the branch in this case.
I shoot a lot of birds in dense bush conditions and, for me, the best method is single point focus locked to the centre of the Field of View. I have focus removed from the shutter button and assigned to the AF-ON button on the top right of the camera back. This allows me to precisely select the eye of the bird, lock focus, recompose and take the shot. This is explained in videos on Back Button Focus: (8) back button focus canon - YouTube.

By the way, I also use single-point exposure, again assigned to the * button (to the right of the AF-On button): there is no guarantee that what you want to focus on will have the 18% reflectance that a camera sensor expects, so I want a different control for that from focus. I select a mid-reflectance value somewhere in the image, lock it, then do the focusing procedure above. Once you practise it for a while, you get very, very fast with this and the combination are game changers for wildlife and sports photography, especially with the fantastic eye tracking of the R5.

The following image, although not of a bird, what shot with this technique, through extremely dense foliage within which the reclusive Red Panda was sitting. It was about 10-12m (38-45ft) away from me at the time.
Red Panda@10m: R5, RF 200-800@ 600mm, f/9, 1/500sec, ISO-6400

The following two are taken in conditions similar to your example. Again spot focus allowed me to choose the eye of my selected subjects - in the case of the second image, the middle bird.
247mm, f/5, 1/125sec, ISO-3200 277mm, f/5, 1/125ec, ISO-6400

Re: Improve autofocus for birds

rs-eos — Sat, 10 Feb 2024 19:04:13 GMT

DSLRs and MILC cameras do not offer digital zoom. Unless you can get physically closer, you'll want to look at longer telephoto or super telephoto lenses. The longer the focal length, the narrower the angle of view, so that will help with eliminating much of the surrounding and distracting elements.

Re: Improve autofocus for birds

Waddizzle — Sat, 10 Feb 2024 19:17:25 GMT

Photographing a bird on a branch is one of the more challenging shooting scenarios. It is a genuine test of the photographer, not the camera gear.

Re: Improve autofocus for birds

johnrmoyer — Sat, 10 Feb 2024 20:21:35 GMT

I also use EOS R5 to photograph small birds far away. I have set eye detection enabled, priority to detect animals, and Face + tracking , and servo AF. I do not use back button focus, because the eye detection and tracking works for me. I would use single point focus for birds on my EOS 80D, but do not use it on my EOS R5.

If the camera cannot find the eye of a small bird far away, then I use 1.6x crop mode and that usually helps.

For this photo, the camera could not find the eye of the bird until I switched to crop mode. I have the C3 settings on the camera saved as crop mode.

F Number 11.0
ISO 2500
Shutter Speed Value 1/512
Focal Length 800.0 mm
Camera Temperature 25 C
Focus Distance Upper 18.82 m
Focus Distance Lower 15.17 m
Lens Model EF100-400mm f/4.5-5.6L IS II USM +2x III

Song Sparrow (Melospiza melodia) in cattails (Typha angustifolia) at Salt Plains National Wildlife Refuge in Alfalfa County, Oklahoma, United States on February 9, 2024

Re: Improve autofocus for birds

luciano — Sat, 10 Feb 2024 20:31:47 GMT

Thanks for useful reply. Does the back button focus work best for subjects that are stationary? Birds like the Great (Parus major) in my photo above are constantly on the move.

Re: Improve autofocus for birds

johnrmoyer — Sat, 10 Feb 2024 20:27:01 GMT

There is a magnified view offered by the camera for some focus methods, but not others. https://cam.start.canon/ky/C003/manual/html/UG-04_AF-Drive_0050.html#AF-Drive_0050_7

Magnified View

To check the focus when the AF method is other than [

+Tracking], magnify display by approx. 6× or 15× by pressing the

button (or tapping [

]).

Magnification is centered on the AF point for [Spot AF], [1-point AF], [Expand AF area:

], and [Expand AF area: Around] and on the Zone AF frame for [Zone AF], [Large Zone AF: Vertical], and [Large Zone AF: Horizontal].
Autofocusing is performed with magnified display if you press the shutter button halfway when set to [Spot AF], and [1-point AF]. When set to AF methods other than [Spot AF] and [1-point AF], autofocusing is performed after restoring normal display.
With Servo AF, if you press the shutter button halfway in the magnified view, the camera will return to the normal view for focusing.

Caution

If focusing is difficult in the magnified view, return to the normal view and perform AF.
If you perform AF in the normal view and then use the magnified view, accurate focus may not be achieved.
AF speed differs between the normal view and magnified view.
Continuous AF and Movie Servo AF are not available when display is magnified.
With the magnified view, achieving focus becomes more difficult due to camera shake. Using a tripod is recommended.

Re: Improve autofocus for birds

luciano — Sat, 10 Feb 2024 20:28:49 GMT

1.6x crop mode might be what I need - this is basically digital zoom right? Can I assign it to a single button that will enable/disable it?

Re: Improve autofocus for birds

Tronhard — Sat, 10 Feb 2024 20:29:15 GMT

The two images of birds, like many small ones, are constantly on the move - they don't stand still for long at all - I suspect this is a protective behaviour as large ones are more static. This works for me and, like John, I do use eye tracking for birds, it's just that I use single point to lock onto the bird of choice first.

Re: Improve autofocus for birds

Tronhard — Sat, 10 Feb 2024 20:35:28 GMT

1.6 or 1.3 crop modes simply reduce the area to be shot and boost the image in the viewfinder (depending on configuration), so you lose pixels. I do use this myself, but only to boost FoV performance, but it comes at a cost of reducing your pixel count by a factor of 2.56, thus the 45MP will reduce to 17Mp on a 1.6 crop.
I don't see this as being effective in location of the focus point. If focus is set to area focus, it will still seek the closest point within the FoV. Eye tracking would normally override this, but occasionally vegetation or other objects can fool the system and there can be issues if more than one bird is present: hence my personal solution.

I have not been able to assign crop factor to a single button on its own. You might be able to set this up as part of an overall configuration, and store that to one of the C modes.

Re: Improve autofocus for birds

johnrmoyer — Sat, 10 Feb 2024 21:05:59 GMT

@luciano wrote:
1.6x crop mode might be what I need - this is basically digital zoom right? Can I assign it to a single button that will enable/disable it?

It is not digital zoom unless you use software outside of the camera later. I have the C3 mode set to 1.6x and Av. I do not think a singe button can enable/disable crop mode. If I will end up cropping later anyway, then nothing is lost by cropping 1.6x when I make the photo. In my example, even at 800mm much cropping would have been needed. I cropped my example to 3600x2400 and then reduced it to 50% when I put it on my web server. The 1.6x crop mode is only a few less pixels than I got with my EOS 80D.

Others say that the 1.6x crop mode does not help eye detection. Yesterday when it was cloudy and the bird was among foliage, the camera was focusing on everything but the bird until I switched to crop mode. This is my experience.

Re: Improve autofocus for birds

Tronhard — Sat, 10 Feb 2024 21:26:13 GMT

"If I will end up cropping later anyway, then nothing is lost by cropping 1.6x when I make the photo." With respect, I disagree with this statement.

This is from the EOS R5 Advanced User guide, P923 - note that number of recorded pixels is reduced when shooting in 1.6 crop. See: Canon EOS R5 Advanced User Guide

Just to be sure that this was not a phenomena related to JPGs, I just shot the same image in 1.0 and 1.6 crops, using RAW and had the image appear cropped and the the pixel size reduced according to that value on the bottom row.

Re: Improve autofocus for birds

johnrmoyer — Sat, 10 Feb 2024 21:47:19 GMT

@Tronhard wrote:
"If I will end up cropping later anyway, then nothing is lost by cropping 1.6x when I make the photo." With respect, I disagree with this statement.

This is from the EOS R5 Advanced User guide, P923 - note that number of recorded pixels is reduced when shooting in 1.6 crop. See: Canon EOS R5 Advanced User Guide
...
Just to be sure that this was not a phenomena related to JPGs, I just shot the same image in 1.0 and 1.6 crops, using RAW and had the image appear cropped and the the pixel size reduced according to that value on the bottom row.

In the case of my example, I ended up cropping to 3600x2400. None of the missing pixels would have been used. I could not get closer to the bird, because one is restricted to staying on the trails at that wildlife refuge. The reduced pixels when I use the 1.6x crop on my EOS R5 is only a few less than on my EOS 80D and is a few more than on my EOS 500D. I knew in advance that the extra pixels would be discarded.

I did shoot that photo with DPRAW and used Canon DPP to increase the fine detail contrast in the DPRAW "Fine Tuning Sharpness" tool.

Re: Improve autofocus for birds

Tronhard — Sat, 10 Feb 2024 21:51:52 GMT

I totally agree that cropping a FF image in post and doing so via the in-body camera are very similar, the main benefit in the R5 being one sees a magnified image in real time, which is convenient for composition. I just wanted to clarify that using 1.6 crop mode will reduce the image size and the full image is not stored as I took your comment to suggest.
All that said, I think that the OP's issue is not the FoV but that his camera was focusing on the nearest object according to the box displaying the point of focus. That is why I suggested taking more control of that, to locate the focus point on the bird's eye (especially when there is more that one bird), combined with eye tracking to follow it, once selected.