Canon RF 50mm f/1.8 STM specifications

No it is a double gauss formula and appears to be the same as used in the 1964 Canonet rangefinder camera where the same optical formula appeared as a 45mm f/1.7 lens. The fifth element is aspherical in the new version. (As opposed to the other Fifth Element which was a rather lovely Milla Jovovich.
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I don't know what reputation this camera had as far as IQ goes, but I do remember that the simple double gauss 5 element 5 groups 40mm f/1.9 in the 1981 Canon Sure Shot AF35ML was very sharp indeed. In fact annoyingly so; it was better than my Nikkor lenses at the time.

Yeah. I'll say it again... this will be a great lens for RF owners to have in their bag, but don't expect any miracles. That extra aspherical element will no doubt increase sharpness at large apertures, but will also not do any favors for smooth bokeh. I predict the old EF STM version will have smoother background blur, but this new version will be sharper. So pick your poison.

Similar for the RF 85 F2 vs the old EF 85. Sharper yet harsher backgrounds.
 
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Interesting stuff. Let me complain, but still be happy (i.e. price): filter thread is odd size, # of apeture blades is lacking but 7 is better than 5 (...), and cool they have moved away from double gauss lens design (right, or is it just -- different..?). It will likely be my first RF lens for my EOS R (still anxious about selling my EF lenses..!).
Don't sell your EF lenses. They're still highly versatile and have "character" like the gen 1 70-200/2.8L IS....at least, that's what I keep telling myself.
 
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trulandphoto

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Sorry for being late in the thread but does this come with a hood? Even an additional cost might interest me. I own the pancake and it is a pain to use it outdoor or near a window light. Third party hoods don't always deliver. The price is really fantastic for the time I need a 50mm, and if a native hood is available, I am all for it.
A good 52mm screw on hood for the 40mm pancake (and the EF-S 24mm and RF 35mm as well) is Canon's LH-DC20 designed for the Powershot S* IS series. You can probably find them used and cheap. I don't know why Canon doesn't market it for these lenses.
 
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Del Paso

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Sorry for being late in the thread but does this come with a hood? Even an additional cost might interest me. I own the pancake and it is a pain to use it outdoor or near a window light. Third party hoods don't always deliver. The price is really fantastic for the time I need a 50mm, and if a native hood is available, I am all for it.
I guess it will be optional, as usual with non L lenses.
By the way, I have and use the 40mm pancake with its Canon lensshade (ES 52), no issues outdoors.
 
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LSXPhotog

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This is a really realistic price for the lens and I'll certainly be picking one up. I am most pleased to see a new optical formula because the old lens was not something I wanted to relive. I appreciate these lenses for their size, weight, and price when I want to walk around NOT for work and when I travel.
 
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Sporgon

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I am most pleased to see a new optical formula because the old lens was not something I wanted to relive.
I think you'll find that the "new optical formula" is at least 56 years old if you have a look at the first page of this thread ;)
 
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Joules

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I think you'll find that the "new optical formula" is at least 56 years old if you have a look at the first page of this thread ;)
You keep saying that, but do you really mean it? They look similar at a first glance, but not identical. Not to mention important aspects such as coasting, materials and modern manufacturing tolerances. Can we please wait for actual results before writing off this lens?
 
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You keep saying that, but do you really mean it? They look similar at a first glance, but not identical. Not to mention important aspects such as coasting, materials and modern manufacturing tolerances. Can we please wait for actual results before writing off this lens?
Yes. And no.

No reason for it to be written off, particularly given the price, but the Double-Gauss design has intrinsic limitations, https://www.lensrentals.com/blog/2011/08/lens-geneology-part-1/ and given the comments of 6 element designs being at their limit at f2.0 it seems Canon are pushing hard with their design with 6 elements and f1.8.

The lens isn't going to break any new ground, and there is no reason why every lens should, but people would be better expecting modest results and be happily surprised than think Canon have rewritten any design rules.
 
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Sporgon

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You keep saying that, but do you really mean it? They look similar at a first glance, but not identical. Not to mention important aspects such as coasting, materials and modern manufacturing tolerances. Can we please wait for actual results before writing off this lens?
Who's writing it off ? In a previous post on the subject I stated that the very simple double gauss lens used in the 1981 era Sure Shot AF35ML was very sharp indeed. But the fact is the basis of this optical formula was used by Canon 56 years earlier, and indeed many other 'modern lenses' are quite old formulas too.

Certainly modern coatings, tolerances, etc make a difference. Look how sharp the 50mm STM lens is in the (very) centre at f/1.8. It's miles better than the old one.

But Canon haven't invented a new version of the classic double gauss design for this lens, they have modified an old one.

I apologise if pointing this out has dashed hopes of an up-to-the-minute 2020 lens design.
 
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Joules

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Who's writing it off ? In a previous post on the subject I stated that the very simple double gauss lens used in the 1981 era Sure Shot AF35ML was very sharp indeed. But the fact is the basis of this optical formula was used by Canon 56 years earlier, and indeed many other 'modern lenses' are quite old formulas too.

Certainly modern coatings, tolerances, etc make a difference. Look how sharp the 50mm STM lens is in the (very) centre at f/1.8. It's miles better than the old one.

But Canon haven't invented a new version of the classic double gauss design for this lens, they have modified an old one.

I apologise if pointing this out has dashed hopes of an up-to-the-minute 2020 lens design.
Well, it appeared to me as if you were trying to demonstrate that Canon were just recycling an old design here (what is lovingly named 'crippling' when talking about camera bodies. See M50 II discussion for recent examples). And I felt like questioning that thought since I don't believe that no effort has gone into the optical design here, even if the result is just a minor tweak.

Sorry if I misinterpreted your intentions here. It just came off as 'painting the devil on the wall' to me, to use a German proverb.

Canon can make great low end offerings. If this design truly is so close to an old one, I am sure there will be a benefit associated with this. And if it is simply reduced manufacturing costs, that's still not a negative if it allows Canon to stay lucrative even at the shrinking low end of the market.
 
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Sporgon

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Well, it appeared to me as if you were trying to demonstrate that Canon were just recycling an old design here

They are ! (With some modern tweaks) ;)

But that doesn't mean it's going to be bad. My favourite lens, albeit a bugger to use, is the Takumar 55mm f/1.8 from the '60s. Now there is a lens that has beautiful rendering, but at the expense of sharpness at 1.8, although as long as focus is very accurate it is acceptable. However it wouldn't be 'acceptable' on a modern test chart. If Brian at TDP had it on his 'lens quality' crops you'd cringe.

I'm guessing that with this new 50 Canon have gone for sharpness / resolution over rendering. It may be that it is sharper across the frame than the 50 STM but probably won't give the same separation as the 50 STM although that lens itself isn't a patch on the old 55/1.8 Takumar, due, I believe, to the quality of the glass and the curvature and bonding of the rear doublet.

I'm sure the RF 50 will certainly be superb 'bang for buck'.
 
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