Thank you, Lukas Haupt, for pointing out in another thread (https://www.canonrumors.com/canon-to-release-new-firmware-for-the-eos-r-later-this-month/) the problem of the R not using the 600ex (or 580ex) AF Assist Beam.
You are correct. After doing some digging, including the user manual, I now see that this is an issue with IR beams, which is what the 600ex and the 580ex use. Darn!
And the little LED on the camera can be nearly useless. Even with the Rf 24-105mm f/4, if within seven or so feet of the subject, the lens barrel blocks the AF assist beam in a big area of the frame, such as in the center. With the lens hood on, things are much worse!
Seems like a hotshoe LED assist would work--but then no flash!!!
At least the series of strobe bursts still works. I have that disabled on my 5DIV, as it is unnecessary and distracting, but, on the R, it has to be used.
Sigh...Always something with tech.
Any interesting work arounds? Apparently this is a problem with mirrorless, not some EOS R bug.
Does anybody feel like this is a "gotcha" that wasn't mentioned in reviews and hype? Even the user manual kind of avoids the topic directly except on page 295, "An LED AF-assist beam is fired by LED-equipped external flash units."
The 600ex is apparently IR, even though we can see the red grid!
Here's a link spelling it out:
fstoppers.com
You are correct. After doing some digging, including the user manual, I now see that this is an issue with IR beams, which is what the 600ex and the 580ex use. Darn!
And the little LED on the camera can be nearly useless. Even with the Rf 24-105mm f/4, if within seven or so feet of the subject, the lens barrel blocks the AF assist beam in a big area of the frame, such as in the center. With the lens hood on, things are much worse!
Seems like a hotshoe LED assist would work--but then no flash!!!
At least the series of strobe bursts still works. I have that disabled on my 5DIV, as it is unnecessary and distracting, but, on the R, it has to be used.
Sigh...Always something with tech.
Any interesting work arounds? Apparently this is a problem with mirrorless, not some EOS R bug.
Does anybody feel like this is a "gotcha" that wasn't mentioned in reviews and hype? Even the user manual kind of avoids the topic directly except on page 295, "An LED AF-assist beam is fired by LED-equipped external flash units."
The 600ex is apparently IR, even though we can see the red grid!
Here's a link spelling it out:
Why Mirrorless Autofocus Means Trade-Offs
Mirrorless cameras like the Sony A7 don’t use a traditional phase detect autofocus. While this enables popular features like eye tracking autofocus, it brings a number of tradeoffs, which could be a deal-breaker for certain applications. Two Systems Enter The phase detect system, typically used...
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