Is there any test data available characterizing the performance of Canon's "AI Servo AutoFocus"?

I am of some opinion about Canon's "AI Servo AF". However, I am aware that it is a question-and-answer forum, not a discussion forum. Therefore, I will ask my question as follows:


Does any one have an objective test (or a series of tests) that clearly shows the limitations (or failures) of the Canon AI Servo AF autofocus to track and maintain focus on moving subjects?

I do not have much experience in animal photography. Maybe the "failures and limitations" are mine alone. When one looks for reports or blog posts that document the "limitations" of AI Servo AF, there is virtually nothing that is critical of his performance. Still, I have the feeling that in a relatively short time I have gathered objective evidence suggesting that Canon's Phase Detected AF system is not quite ready for prime time – in at least some applications.

I'm trying to catch small birds in flight. Difficult? Yes of course. But does that mean that Canon is receiving absolution from the community because the task is arduous? On the contrary, many online articles sponsored by Canon claim that the Canon system can handle moving subjects and flying birds. Exceptions to Canon's claims seem to be rare and pronounced in passing.

I wondered if people were reluctant to express themselves – perhaps because reviewers could not risk criticizing their sponsors, or perhaps as in this old story. I have knowledge that make bird photography for many years. When I shared my thoughts with them, the only memorable comment was: "You simply do not know how much better the current systems are than the old ones." It may be fine, but complacency and progress rarely go hand in hand!

post-processing – How can I address the lack of support for Canon's new CR3 Raw format in the software I use?

Canon's new Cr3 file format can not be processed with any of the best editing software. Lightroom Classic does not support it, any more than DX0, or Luminar / Skylum. The Lightroom CC subscription will do it, but I do not want to use any subscription program … I do not want to use Canon's DPP conversion because it does not provide the level of tuning that I I am used to it.

Do you have any ideas for solving the problem until companies offer support for CR3 files?

flash – How can I use a fast flash that does not work with the non-standard hoof of Canon's low-end cameras?

The optical trigger by the built-in flash of the camera can work, but also has significant limitations and can be more frustrating than it is worth it.

Theoretically, this can be triggered by an extinct radio, which would be a good use. Unfortunately, it seems that this Yongnuo model only works with triggers that will not work with your camera either.

Therefore, I really think your best bet is to return it (or sell it used, if return is not possible) and get something that works – Which Speedlites can work with the non-standard Canon shoe that we find on their low-end camera models ?. There are several options that are no more expensive than this one. (And many that are much more flexible.)

Or, if you plan to replace your camera in any case, stick to it and buy a high-end model with the standard center pin. It is unlikely that Canon removes this entirely from models intended for professionals and serious amateurs, because there would be a huge reaction. Instead, they use it as a differentiator to keep this market segment away from the cheapest purchases. It is highly likely that this will also climb into the model food chain in the middle segment in the next few years, so … If this is important to you, it is probably worth taking into account.

Canon's best lens for a maximum depth of field of 70 mm?

Have you considered spending less and getting more?

I headed directly to Zerene Stacker or similar and took half a dozen photos while pulling the focus ring manually.

In this case, you will not fight either the diffraction limit you get with narrow openings.

A diaper…

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11 layers stacked

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I've been better since, but this one shows an extreme effect, front-back.

Time needed to shoot about a minute; stack, about a minute – it's really a pretty fast process once you understand the principle.

For something as big as glasses, you could probably do it in f8 in 3 or 4 layers.

You can either focus, zoom, or get a macro rail, moving the camera as a whole. I've tried all three and I can not make up my mind. After each pull, I wait a few seconds to reduce any potential tremor on the tripod, then a delay of 1 second. I also use a wired version.

Do Nikon cameras have a similar feature to Canon's Exposure Safety Shift?

I am not aware of any Nikon with a security shift feature.

Canon's safety offset only comes into play if a required exposure setting is not available … ie. That Ap / ISO settings require an exposure of 1/8000, but that the camera can only take 1/4000. Personally, I do not really see the benefits …

Nikon's behavior is somewhat similar. If you use Auto ISO with a minimum shutter speed and set maximum ISO limits, the camera cancels the minimum SS setting once the max ISO setting is reached instead of allowing underexposure to occur.

Why is Canon's 17 cm focus distance a macro when a focus distance of 16 cm is not a macro?

The original definition of "macro" is that the image on the film is at least as big as the object in reality. With the amount of small sensor cameras around, this definition is of dubious utility. A more "efficient" macro would be more relevant when the imaged area is not larger than 24mm × 36mm, the imaging area of ​​a 35mm (or full frame) digital camera, regardless of the actual size of the sensor. I'm not sure, but I do not think that definition is really used.

Instead, "macro" is used for an enlarged range of zooms (compact or ILC) where the potential magnification of the object is maximized on the large the end of the zoom lens due to the minimum focus distance reduced by more than the viewing angle when zooming increases outside. This close-up mode causes extreme distortion of the perspective (sometimes desired to emphasize an object in a miniature representation of its environment) and a very close focusing distance that often causes shadow problems.

Enlarged lenses or screwed diopters (achromatic for optimum quality) can be used to shift the maximum magnification of the wide angle to the telephoto zoom, thus providing greater perspective, positioning and lighting conditions relaxed.

In reality, dedicated macro lenses do not get bigger by rearranging the optical recipe of a normal zoom lens at the wide end to reduce the minimum focus distance: their optical recipe does not match not the priority at the best image quality at distances close to + ∞ as that of a typical zoom lens and they do not have the minimum focus distances generally important for long focal lengths of "normal" zoom lenses.