Here is what Canon is announcing next, including the EOS R7, EOS R10 and RF-S lenses [CR3]

neuroanatomist

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This isn't quite what I was getting at in my original proposition - I doubt RF users would be that concerned with EF-M glass and I realise going the other way round, to use EF-M on RF isn't at all practical or cost-effective.

My thought was what if RF-S was simply EF-M with a new name, so you could use existing EF-M lenses and also RF lenses via an adaptor - exactly the same way as EOSM can use EF and EF-S lenses. Of course, this does mean you wouldn't be able to take your RF-S glass with you if you wanted to "upgrade" to FF. Similar (compatibility wise, not physically) to EF-S and EF in that regard.
What you're suggesting is not really feasible.

Using existing EF-M lenses on an RF mount would require an adapter with optics, and likely result in substantial image degradation.

EF and EF-S lenses have a longer flange distance (44mm) than RF (20mm) or EF-M (18mm). That allows room for an adapter that is really just a spacer, without optics. Mounting an RF lens on an M body means a 2mm adapter, not really practical to use and no one has made one (nor, I suspect, will anyone). Mounting an EF-M lens on an R body would require the lens to sit 2mm inside the body, and that's not possible. Thus, any adapter would need optical elements like the old FD-to-EOS adapter.
 
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Blue Zurich

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I think the $650 RF 100-400 would be the ideal, affordable and small tele zoo for crop sensor bodies. And the RF 24-105 is quite compact, light and affordable. No, they’re not M-small, but M-small comes with quite few limitations. Other than ultrawide, Canon already covers 16-400mm with good, affordable small lenses, thar are well-suited for the rumored R10, IMHO.
Exactly, many are throwing around the incorrect premise that Canon has no small lenses which would make for balanced R Crop bodies. Rubbish. RF 16, RF 50, 35 STM, 85 STM, 24-105 STM, even the RF 70-200L f/4 would work on a body just a smidge larger than an M5. I could also see some pancakes in the future for crop RF. All these and far greater optics to go along with it. Sounds like pure win.
 
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May 11, 2022
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RF 50, 35 STM, 85 STM, 24-105 STM, even the RF 70-200L f/4 would work on a body just a smidge larger than an M5.
These all have useless viewangles on APS-C, you pay full-frame glass and at least the 24-105 & 70-200 are NOT small. On APS-C a 50mm = not really a portrait lens, 35mm = not really a 50mm, 24-105 missing the wide end etc. EF-M22 is a small lens, EF-M32 is small and a true 50 equivalent etc.

1652453051993.png

This is why a a unified mount is shit. If you look at at EF-mount, Z-mount or F-mount the APS-C lenses were always bigger than needed, half assed and missing important lenses, b/c you can always gEt ThE fUlLfRaMe LeNs and ApS-c Is EnTrY tO FuLlFrAmE.
 
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HMC11

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This isn't quite what I was getting at in my original proposition - I doubt RF users would be that concerned with EF-M glass and I realise going the other way round, to use EF-M on RF isn't at all practical or cost-effective.

My thought was what if RF-S was simply EF-M with a new name, so you could use existing EF-M lenses and also RF lenses via an adaptor - exactly the same way as EOSM can use EF and EF-S lenses. Of course, this does mean you wouldn't be able to take your RF-S glass with you if you wanted to "upgrade" to FF. Similar (compatibility wise, not physically) to EF-S and EF in that regard.
To adapt EF-M lenses for RF mount would require an adapter with optical elements as the Flange distance of the EF-M is actually 2mm shorter. This could add not inconsiderable (cf EF-M lenses) weight and length to the whole setup, negating the light weight and small size advantages of the EM-M system. On the other hand, adapting EF & EF-S lenses on the M and RF mount are much easier, as the adapter is essentially just a spacer (with electronics that allow for communication between the lens and the camera body). Using adapter with optical elements to adapt lenses for shorter flange distance to lenses for longer flange distance system does not seem to have happened yet, as far as I know, for the major camera companies.
 
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May 11, 2022
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Sure, sure. No one uses the 85mm focal length on FF for portraits. :rolleyes:
50 * 1.5/1.6 =/= 85

There is a reason why most camera manufacturers are producing 85mm lenses and not 70-75mm. Many ppl also complain that the standard 24-70 f2.8 is too short for portraits. So no, the 50mm on APS-C is not a portrait lens.
 
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neuroanatomist

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50 * 1.5/1.6 =/= 85

There is a reason why most camera manufacturers are producing 85mm lenses and not 70-75mm. Many ppl also complain that the standard 24-70 f2.8 is too short for portraits. So no, the 50mm on APS-C is not a portrait lens.
Please, just stop. You're embarrassing yourself. 50mm x 1.6 = 80mm. You're suggestion that being 5mm shorter than the classic 85mm (a 9% difference) means it's not a portrait lens is simply asinine.

You'd have been better off arguing based on perspective, since that is solely based on distance to subject and with a 50mm lens on APS-C you'd be further from the subject than with 80/85mm on FF. But even that doesn't hold water, because pretty much the whole 70-200mm FF range is considered a 'flattering' perspective, and that encompasses the subject distance of an 50mm lens on APS-C. 70-200/2.8 zooms are very frequently used by portrait/wedding photographers for a reason. They don't start at 85mm, do they? In fact, both Canon and Nikon offered 80-200/2.8 lenses, and updated them to start at 70mm.
 
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Blue Zurich

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Jan 22, 2022
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These all have useless viewangles on APS-C, you pay full-frame glass and at least the 24-105 & 70-200 are NOT small. On APS-C a 50mm = not really a portrait lens, 35mm = not really a 50mm, 24-105 missing the wide end etc. EF-M22 is a small lens, EF-M32 is small and a true 50 equivalent etc.

View attachment 203522

This is why a a unified mount is shit. If you look at at EF-mount, Z-mount or F-mount the APS-C lenses were always bigger than needed, half assed and missing important lenses, b/c you can always gEt ThE fUlLfRaMe LeNs and ApS-c Is EnTrY tO FuLlFrAmE.
I used all sorts of L glass without complaint on my M5, I guess the size of your mitts makes or breaks your options. YMMV. plus I don't limit my creativity by 'classic' focal lengths prescribed by history and media.

oh and do you think a telephoto lens such as 400 5.6L or 100-400L let alone larger white teles fit with the balance you desire on 7D/5D Ssize body? No, but we use them with proper technique and for many years, without relying on stabilization.
 
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jordanisaak

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Jan 29, 2022
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I agree that a slight variance from the "traditional" focal lengths is no big deal. I didn't care that my 50mm was actually 80mm equivalent instead of an 85mm, or that my 24mm was a 38.4mm equivalent instead of a 35mm or 40mm. Close enough is close enough.

But, every time somebody trots out the argument that RF lenses would work great on APS-C, I have to think that they haven't been paying attention to the other mirrorless lineups - most of these lenses only are good options for APS-C in a vacuum where other systems don't exist. There are more attractive APS-C options in terms of cost, optical performance, and/or bulk/weight for pretty much every RF lens.
 
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adrian_bacon

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Aug 12, 2020
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On APS-C a 50mm = not really a portrait lens
Yes it is. In fact the 40mm STM pancake is an awesome lens for portraits on APS-C. I've shot a massive pile of couples portraits with a little Canon Rebel SL1 and the 40stm, and single person headshots with the same camera and the nifty 50. Back then, if you wanted to get into studio portrait photography, those two lenses and an entry level to mid level APS-C body were a very inexpensive and performant way to get into it. Add the EF-s 24mm pancake if you wanted to do more family sized group stuff and the ef-s 10-18 stm for larger group shots and for less than $2K you had a complete studio setup. I spent more money on lights and props than I did camera gear.

These days, I shoot a lot of studio stuff on an RF FF with the RF 70-200 at 70-100mm and with the RF 50STM or 35STM if I need to go a bit wider.

The point is, if you have APS-C camera and you're shooting a a single person portrait from about 6 feet away from the subject, 50mm is about right.
 
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gregedwards69

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What you're suggesting is not really feasible.

Using existing EF-M lenses on an RF mount would require an adapter with optics, and likely result in substantial image degradation.

EF and EF-S lenses have a longer flange distance (44mm) than RF (20mm) or EF-M (18mm). That allows room for an adapter that is really just a spacer, without optics. Mounting an RF lens on an M body means a 2mm adapter, not really practical to use and no one has made one (nor, I suspect, will anyone). Mounting an EF-M lens on an R body would require the lens to sit 2mm inside the body, and that's not possible. Thus, any adapter would need optical elements like the old FD-to-EOS adapter.

To adapt EF-M lenses for RF mount would require an adapter with optical elements as the Flange distance of the EF-M is actually 2mm shorter. This could add not inconsiderable (cf EF-M lenses) weight and length to the whole setup, negating the light weight and small size advantages of the EM-M system. On the other hand, adapting EF & EF-S lenses on the M and RF mount are much easier, as the adapter is essentially just a spacer (with electronics that allow for communication between the lens and the camera body). Using adapter with optical elements to adapt lenses for shorter flange distance to lenses for longer flange distance system does not seem to have happened yet, as far as I know, for the major camera companies.

FWIW, I am NOT suggesting EF-M lenses to be adapted for use on the current RF mount. I realise that's not really possible, and it's pretty fruitless endeavour.

What I WAS suggesting is that RF-S and EF-M mounts could potentially be the same thing. So you could natively use EF-M lenses on an RF-S body, and use RF lenses on RF-S bodies with an adapter. However, I note neroanatomist's comment regarding the 2mm adaptor challenges and realise now that it's not really possible.

It was just a rumination. We'll wait and see what happens.
 
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Bob Howland

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I think they'd make a big splash with M6II guts in an AE-1 style body. It would generate a lot of publicity and be hipster heaven!
As somebody who owned an AE-1 and A-1 25 years ago, that comment makes no sense at all. The AE-1 used an FD mount, was manual focusing with an optical viewfinder and had no P or S modes.
 
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Bob Howland

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50 * 1.5/1.6 =/= 85

There is a reason why most camera manufacturers are producing 85mm lenses and not 70-75mm. Many ppl also complain that the standard 24-70 f2.8 is too short for portraits. So no, the 50mm on APS-C is not a portrait lens.
And a lot of people use 24-70 lenses for portraits. Just step backwards and don't fill the frame with the portrait. Effectively that creates about a 1.2x crop of the FF sensor, resulting in an 84mm lens. Of course you lose pixels in the process, but if your using, for example, a 5Ds, you probably have pixels to spare.
 
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Bob Howland

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FWIW, I am NOT suggesting EF-M lenses to be adapted for use on the current RF mount. I realise that's not really possible, and it's pretty fruitless endeavour.

What I WAS suggesting is that RF-S and EF-M mounts could potentially be the same thing. So you could natively use EF-M lenses on an RF-S body, and use RF lenses on RF-S bodies with an adapter. However, I note neroanatomist's comment regarding the 2mm adaptor challenges and realise now that it's not really possible.

It was just a rumination. We'll wait and see what happens.
So you suggest making an M7 and calling it an R7?
 

Czardoom

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These all have useless viewangles on APS-C, you pay full-frame glass and at least the 24-105 & 70-200 are NOT small. On APS-C a 50mm = not really a portrait lens, 35mm = not really a 50mm, 24-105 missing the wide end etc.
I suggest you take up photography. It's a nice hobby. Then you might learn a little bit about lenses.
 
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mdcmdcmdc

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As somebody who owned an AE-1 and A-1 25 years ago, that comment makes no sense at all. The AE-1 used an FD mount, was manual focusing with an optical viewfinder and had no P or S modes.
It also had a mirror and used film so you’re right. Bad idea.
 
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