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Mirrorless Pro-Class Cameras with Interchangeable Lenses Sony A7, A7R and similar high end cameras that can serve as the sole cameras on Pro-event assignments.

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Old September 4th, 2018, 01:42 PM
Doug Kerr Doug Kerr is offline
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Default Canon interchangeable lens non-SLR cameras

I have been chastised (good-natiuredly) by an esteemed colleague here for following what I thought was an "unwritten law" (although I must have seen it written someplace, or I never would have heard of it - how paradoxical!) that we should not in this learned arena discuss cameras that had not yet been announced by their manufacturer (or importer, or foster parents, or whatever).

Silly me.

It is generally considered that on 2018.09.05 (tomorrow, at this writing) Canon will announce the first member of an important new camera family, evidently to be called the "EOS R" family. This will be an interchangeable lens camera with a new mount, called the "RF" mount, and the first four lenses to have that mount will be announced at the same time.

The camera itself will have what I call an "eight-thirds" size sensor (nominally 24 mm × 36 mm, reasonably called a "full-frame 35-mm format, often called a "full-frame" format), and will not use the SLR configuration. This whole set of properties can be summarized with the code (not an acronym, since it is not reasonably pronounceable), "FF35NSLRILC".

Canon has also fairly recently introduced another new camera series, the "M" series, also interchangeable lens cameras not using the SLR formulation, these with what I call a "five-thirds" size sensor (also often called "APS-C" size or "1.6x" size").

These cameras also have a new mount, the EF-M type, and there exists a modest stable of lenses with that mount.

As might be suspected from the smaller native sensor size of the "M' cameras compared to the "R" cameras, lenses for the "M" cameras tend to be a bit smaller than lenses for the "R" cameras, and in fact all the extant "M" bodies are typically smaller than the apparently-about-to-be-announced "R" camera.

Thus the photographer who wants a relatively compact and lightweight interchangeable-lens non-SLR rig may opt to build her arsenal from "M" things rather than "R" things. Those who believe that true fulfillment of our purpose here on Earth only comes from the use of a format as big as possible but not over 24 mm × 36 mm may opt to build her arsenal from "R" things (or who feel that only a large camera body will feel right in her hands). And so forth.

There is over the last couple of days in the Canon cyberspace some gnashing of teeth and rending of garments over how misguided Canon is to have entered the interchangeable-lens non-SLR world with two distinct families of lenses.

Simplistically speaking, we probably cannot put an EF lens on an M body (as, among other things, there is an incompatibility in back flange distances between the two mounts), and if we put an EF-M lens on an R body (as will doubtless be provided for by some intrepid adapter manufacturer), since (assuming an adapter with no internal optics) the EF-M lens will not generate an image circle that covers an eight-thirds sensor. But then we could . . .

I take rather a different outlook. If I want a smaller Canon interchangeable-lens non-SLR system, I will get an M body and a couple of EF-M lenses. If I feel I must shoot in the eight-thirds format, I will get an R body and a couple of RF lenses. That of course is easy for me to say, as I will probably not do either.

Well, I hope this has sufficiently broken the drought of information on upcoming but (as of this writing) unannounced interchangeable-lens non-SLR camera systems with formats larger than four-thirds.

Tomorrow, or later, maybe: The upcoming but unannounced Panasonic FF35NSLRILC.

Best regards,

Doug
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Old September 5th, 2018, 01:28 PM
Doug Kerr Doug Kerr is offline
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Many reviewers comment on the "large throat diameter" of the new Canon RF lens mount. But its nominal throat diameter (54 mm) is the same as the nominal throat diameter of the EF mount (54 mm).

Of course what is consequential is that the back flange dimension (the distance from the reference surface of the mount flange to the focal plane) is 20 mm, compared to 44 mm for the EF mount. This is very beneficial to lens design, for example making it easier to have a large aperture lens with an appropriate degree of correction for various aberrations.

This means, by the way, that the adapter to use EF or EF-S lenses on an EOS R body (the kind of adapter not having a filter drawer) will be 24 mm thick (flange-to-flange), a little less than one inch. So it is not a cumbersome piece of plumbing.

The RF lenses use a new lens protocol, and in fact a new electrical signal on the data leads, CMOS ("push pull") rather than the "open drain" signal of the EF interface. The camera knows whether an RF lens or an EF-to-RF adapter (and thus ultimately an EF or EF-S lens) is in place and switches the interface mode (both as to the electrical signal and the protocol) to suit. Thus the adapter does not (so far as I know) have to have any electronics in it.

Best regards,

Doug
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Old September 6th, 2018, 03:56 AM
Asher Kelman Asher Kelman is offline
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“The RF lenses use a new lens protocol, and in fact a new electrical signal on the data leads, CMOS ("push pull") rather than the "open drain" signal of the EF interface. The camera knows whether an RF lens or an EF-to-RF adapter (and thus ultimately an EF or EF-S lens) is in place and switches the interface mode (both as to the electrical signal and the protocol) to suit. Thus the adapter does not (so far as I know) have to have any electronics in it.”


Well Doug,

Then that suggests that Sigma and other 3rd part lenses will focus as well!

Of course they could have added a trick to prevent that, but I doubt they would add more complexity that needed for getting two entirely different motor systems to work.

I can’t wait to see a $599 100-400 Sigma lens with ac1.4 or 2x adapter and focusing perfectly down to f = 11.0. That will be revolutionary!

Asher
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Old September 13th, 2018, 08:18 PM
Samir Adnan Samir Adnan is offline
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I have heard a lot about Canon SLR Camera. Actually one of my best friends is using this one for lover 2 years. The one thing I like most is Camera Lenses. Those are really amazing.
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Old September 14th, 2018, 06:06 PM
fahim mohammed fahim mohammed is offline
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Actually a MILC APS-C body might be small. And the lenses could and are small if one restricts oneself to apertures of f2 and bigger. And the zooms generally follow the same pattern. Big, bulky, heavy etc. is relative to the 35mm FF camera lenses.

But, and this is a big but, if one starts getting into the constant f2.8, weather resistant, top performing lenses the mirrorless aps-c sensor based cameras quickly loose their size and weight advantage. It is not limited to mirrorless. My Nikon 17-55 was a match for the Nikon
24-70mm. Add vr into the camera body with decent ergo and one starts to approach 35mm FF territory.

Ask me! I have the Fujinon XF 16-55/2.8, 56/1.2, the 90/2, 16/1.4
Hardly carry them on my travels. Instead the 23/2, 35/2, 50/2 are my lenses of choice.
Those with the XP2 and even the XH1 is a manageable kit for me.
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