Patent: Canon RF 50mm f/1.8

Canon Rumors Guy

EOS 1D MK II
Jul 20, 2010
7,719
353
Canada
www.canonrumors.com
The 50mm f/1.8 is a must lens for pretty much any manufacturer, and it’s safe to say that Canon will be bringing this affordable prime lens to their RF mount.
Canon News uncovered a patent showing multiple different designs for an RF 50mm f/1.8
Canon RF 50mm f/1.8 embodiements:

Focal length: 48.70mm
F-number: 1.85
field angle: 23.95
Image height: 21.64mm
total lens length: 58.55mm
BF: 20.15mm


Focal length: 48.70mm
F-number: 1.85
half angle: (in degrees) 23.95
Image height: 21.64mm
total lens length: 58.55mm
BF: 16.48mm


focal length: 48.70mm
F-number: 1.85
half angle: (in degrees) 23.95
Image height: 21.64mm
total lens length: 58.55mm
BF: 19.38mm
Continue reading...


 

Antono Refa

EOS 6D MK II
Mar 26, 2014
849
128
Just a hair smaller than the RF 35mm f/1.8 IS, it will be compact and reasonably priced, hopefully it will render nicely as well.
The RF 35mm f/1.8 IS has IS, while the RF 50mm f/1.8...

seem to be variations of the simple and venerable double Gauss design
without adding IS. This is not the 50mm lens I'm looking for.

Seems Canon is closing on the quaternity of zoom lenses I'd like in RF mount, though.
 

ColinJR

EOS-R
Nov 27, 2018
32
26
robertsonrep.com
Nice. I would love a small & light fifty for my R. Fingers crossed it has good IQ and better a build than the EF version. I'm using the 1.4 now and even on the adapter it's fine, size wise, but just doesn't produce very good results, IMHO. Colors are drab compared to my L lenses.
 
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SwissFrank

EOS RP
Dec 9, 2018
301
116
Is "total lens length" what's labeled "Td" on the diagram, front to back element? Or is it front to film plane? I think the latter but want to confirm.

Weird to have three designs with exact same spec except backfocus, especially as backfocus isn't especially important. Once mounted I can't see whether it's 1 or 11mm.

OK, so assuming total lens length: 58.55mm includes the distance from back of lens to sensor...

Then subtracting the film-to-flange of 20mm... leaves us with a projection of 38.55mm.

The the 35mm f/1.8ISMac is 74mm length, which I assume includes some inside the camera... anyone know how far it sticks out?

My critical question is that the 35mm is just too long for me to have my camera in my backpack all day every day even when I'm not planning on shooting. Is the 50mm also too long? I don't know. Maybe I should have gotten the Fujifilm camera... as much as I've liked Canon since 1995, this is just too big for my lifestyle as an aging daddy...
 

TonyPM

I'm New Here
Jul 24, 2019
10
2
I wish they put IS on it for a reasonable price. Though I doubt it will have IS, and a reasonable price.

Now that the Eos Rp price is going down it would be interesting to see as part of a standard kit.

The RF 24-240 is looks huge when mounted on the Rp.

Love to see other options, like those pancake lenses on the RF road map. And maybe a 24-105 kit lens a bit smaller than the 24-105 f4 L.
 

mb66energy

EOS 6D MK II
Dec 18, 2011
1,285
193
Germany
www.MichaelBockhorst.de
Pancake, I want a pancake lens hold the syzurp!
Pancake-ability depends more or less on the flange distance, a pan cake lens' focal length is in that region and easy if the flange distance is similar to the sensor diagonal. For EOS R the optimum focal length will be in the 20...24mm region but if you use some simple (=compact) lens design you will have a 4 or 5 stop drop vignetting at f/4. Maybe a 40mm tele construction (with negative element protruding into the sensors direction might make some flat lens (the lens' part outside the camera) but something like the EF 40 will never happen to the RF IMO - or it is of a similar size like the EF 40 with adapter and not exactly pancake. The EF was so simple because it has 40mm FL for a 40 mm flange distance and a 43 mm sensor diagonal.
 

analoggrotto

EOS T7i
Aug 27, 2016
94
40
Pancake-ability depends more or less on the flange distance, a pan cake lens' focal length is in that region and easy if the flange distance is similar to the sensor diagonal. For EOS R the optimum focal length will be in the 20...24mm region but if you use some simple (=compact) lens design you will have a 4 or 5 stop drop vignetting at f/4. Maybe a 40mm tele construction (with negative element protruding into the sensors direction might make some flat lens (the lens' part outside the camera) but something like the EF 40 will never happen to the RF IMO - or it is of a similar size like the EF 40 with adapter and not exactly pancake. The EF was so simple because it has 40mm FL for a 40 mm flange distance and a 43 mm sensor diagonal.
I've suspected as much without a great understanding of fundamental optic design. It is one of those lenses that would be great to allow the full frame camera to come along for a day trip (5D + 40mm Pancake isnt even that combination). But, in even more layman's terms, the length lose from one (lens/body), gets added to the other [body/lens). But this is Canon with three great pancakes for the present EF,EF-S,M, and there has been rumors of RF pancakes, lets hope some of this sees the +light+ of day. ;) cheers
 

TonyPM

I'm New Here
Jul 24, 2019
10
2
There's a road map with 28 and 40mm f2.8 pancake/little lenses. They should put Is on them if their future bodies don't have ibis.