Ramblings and personal preferences ahead. If you are a sensor size or brand adherent look away. Nothing to see here.
I will admit it. I have a 50mm prime lens problem. But not just any 50mm lenses. Nifty fifty lenses specifically. The criteria:
- Small.
- Light.
- Well built.
- Excellent optical performers.
- Sharp.
- Great bokeh.
- Great colors.
- Swift and accurate AF (If AF is available that is.).
- f/1.8 or faster.
- Inexpensive.
The type of lenses that film era SLR camera mounts are filthy with. Some examples:
Nikon Series E Pancake Lens 50mm f/1.8 AI-S
Contax CY Zeiss Planar 50mm f/1.7
Any SLR brand worth their salt knew they had to have an inexpensive 50mm f/1.8 or faster lens in their quiver. How is that for mangling a metaphor? It is likely the first SLR lens many purchased after their kit lens if not purchased with the camera. Most every SLR I ever purchased with a lens had a nifty fifty variant attached to it.
Move to full-frame DSLRs and the same thing applies even though there are fewer brands standing. And some companies seem a bit wobbly nowadays. Pentax’s K-AF perma-mount means that same 50mm f/1.7 above worked just fine on their digital offerings.
Brand new Pentax variants price themselves out of nifty status, but there are used options available on the market.
Nikon has you covered with a NIKKOR 50mm f/1.8G lens that does not cost too much at a bit over $200 and another older design still available new that runs less than $150.
But Canon pulls ahead a bit here. Their latest and greatest Canon EF 50mm f/1.8 STM lens is less expensive brand new and better built than the older Nikon and Pentax lenses mentioned above. A great lens.
And if that is too rich for your blood an older Canon AF 50mm f/1.8 EF costs even less used.
Then came crop mirrorless and their equivalent focal lengths. This was my digital entry point. Micro Four Thirds had 25mm lenses. Most are reasonably priced similar to the full frame DSLR lenses. APS-C has its full-frame 50mm equivalent-ish 30mm and 35mm focal length f/1.8 and faster lenses. But unlike full frame DSLR and MFT lenses these APS-C equivalent factory lenses are often:
- Pricey.
- Not much smaller than full frame DSLR 50mm lenses. Especially when looking at f/1.4 options.

And all of these crop equivalent sensors/lenses have another problem. I have tried a good number of them. You can show me all of the crop to full frame equivalent blind comparisons you want to. It is like a turkey vs. beef burger comparison. In isolation a turkey burger will do. But no matter what you do to the turkey burger I will always choose the beef burger if that option is available.
Similarly no matter what tech, spec, or name brand you throw at a crop sensor and lens all other things being equal I will always choose a full frame sensor and lens if that option is on the table. I have tried many. Panasonic MFT, Olympus MFT, Fujifilm (APS-C), Samsung (APS-C), and Sony (APS-C) covers most. All great 50mm equivalent camera/lens combinations, but it is full frame for me. And with new and used full-frame mirrorless camera prices dropping daily there is little motive to buy into a crop system nowadays in my opinion. With hundreds separating them I would rather a S5 over a GH5S, Z5 over a Z50, RP over an M50, A7c over an a6600, and a… over a… OM-D-M1X?. As much as I like Olympus I am still scratching my head about them releasing that large and expensive Olympus OM-D E-M1X. If anything they should have leaned into the small side of things harder like a tiny new form factor real film PEN reimagining rather than a standard issue digital camera in a film-ish disguise. Anyhoo… I understand that Fuji adherents have a higher price jump to the GFX line, may not be willing to brand jump perfectly happy where they are, and I respect that. I came close to making the jump to GFX myself when a resident of Fuji-La at one point.
Sony being the first to step out into the full frame mirrorless market should have the most 50mm options. And it does. Other than this one category, and maybe one more that I will mention soon, Sony owns the full frame mirrorless lens selection game currently. But none fit the nifty fifty bill for me. At just shy of $900, and not huge but not exactly small either, the Sony Sonnar T* FE 55mm f/1.8 ZA was never considered. Nearly a grand for an f/1.8 prime that is not fifty and larger than I would like does not qualify as nifty. Also leaving the Rokinon/Samyang 50mm f/1.4 off of this list. It is too large and too expensive to be a nifty fifty. The same applies even more so to other lenses like the Sony Planar T* FE 50mm f/1.4 ZA and Sigma 50mm f/1.4 DG HSM Art Lens for Sony E as well. Lenses this large diminish the smaller size and weight promise of mirrorless. Lenses this expensive do not fit the spirit of a nifty fifty. The Sigma DG DN 45mm f/2.8 Contemporary is too slow and expensive also. I will limit this list to the two remaining f/1.8 or faster 50mm-ish native non-adapted lenses that I have actually tried. They both come close, but fall short.
- Oddly as large as the Canon 50mm STM with an MC11 adapter.
- Noisy. Not terrible, but more noise than I expected.
- Slow to focus. I found that the Canon 50mm f/1.8 STM adapted w/an MC11 focused more swiftly and more silently than the native FE. This makes no sense. The Sony is much more prone to becoming confused as well.
- Plasticky. Looks like the excellent in every way FE 85mm f/1.8 that came later, but the 50mm is not built nearly as well.
- Not expensive, but costs more than it should all things considered at almost $250 full price. A lot could be forgiven for about $100 new, but an improved all around gen II version at the same price would be preferred.
Rokinon/Samyang AF 45mm f/1.8 FE Lens for Sony E
- It is 45mm. May not matter to some, but it bugged me. Not everything you read here will be rational. We are discussing photography with dedicated camera gear when a phone will do for many after all. Admittedly a solid optical performer otherwise.
- Feels kind of light and hollow. Works for their near pancake, much smaller, much less expensive 24mm and 35mm f/2.8 lenses, but not here. The f/1.4 triplets (35mm/50mm/85mm) share the same color scheme, but feel considerably more substantial in hand.
- It costs $100 to $150 more than the Sony FE on sale and $200 more at full price. At this price I would stretch for the slower focusing, larger, and heavier Rokinon/Samyang 50mm f/1.4 that can be had for not much more when on sale.
- I understand completely why someone may get on well with this lens, but combine all of these and it is a no for me.
Next up on my full frame mirrorless list is Nikon. Oh Nikon. I have wanted to get back to Nikon since my beloved Nikon D3300 years ago. But I just can’t.do it. The first Z cameras were impressive, but they have been faced with even better cameras on the market or similarly impressive cameras with better lens choices. And the second generation bodies, while not bad cameras, did not add enough and arguably fell behind. And those 50mm lenses. The newer option, the Nikon NIKKOR Z 50mm f/1.2 S, is far too large and expensive for consideration. And the other, the Nikon NIKKOR Z 50mm f/1.8 S, hits the on paper optical spec, but is still quite pricey at almost $600. Also not helping is the size. At a similar spec it is significantly larger than the two Sony f/1.8 options.

For further size reference here is the Z 50mm f/1.8G next to the 1.8G mounted on a D750.

As mentioned their least expensive Z 50mm, the same as RF f/1.8 variant, goes for $400 more than the RF STM and is considerably larger. Optically superior? Perhaps, but in no way I can easily identify based on real world sample images. Spec wise it is largely a wash with the RF STM actually pulling ahead in minimum aperture (f22 vs. f16. No big admittedly.) and minimum focus distance at 11.8″ / 30cm vs the Z’s 1.31′ / 40cm. That last part is actually useful. But the Z 50mm does have 2 more aperture blades at 9 vs 7 or about $200 per aperture blade. Additionally while the Z5 body is a great deal in isolation, when combined with the lens consideration I would be tipped Canon’s way. Especially when you consider the fact that Nikon priced their crop Z50 on top of the EOS RP. I do really like Nikon camera, but I find Sony and Canon options more compelling here..
What of the L Mount Alliance someone may have asked in the back? Welp. Are you seated?

And that is just the lenses. The bodies start at $1,700 or about $2,000 if you are looking for an EVF, mechanical shutter, and an articulating screen. So that is a no from me.
So at this point you may be asking “What the heck does any of this have to do with this blog post title?” Well I am here to tell you.
Sony and Nikon had one job in my little universe. Create a full-frame mirrorless nifty fifty. I can forgive Sony a bit because they hit the camera and lens mark in so many other ways. But, both fell short.
But now on to Canon. The first Canon RF 50mm f/1.2L USM was definitely too large and expensive for me, but I had high hopes for Canon. They nailed it with the DSLR 50mm f/1.8 STM that worked well adapted to Canon full frame mirrorless.
But adapting the lens took some shine off of the experience. No native nifty fifty was available in 2019, only a much more expensive option, so I moved to the Canon RF 35mm f/1.8 IS Macro STM.
A great prime, but it did not stop me from trading the RP. But I knew that if Canon ever did get around to making a native RF 50mm f/1.8 STM that lived up to their DSLR STM I would likely be looking for another EOS RP.
And that is exactly what Canon did in late 2020.
So jump on a new RP? No. That is not how I roll. Especially with the newly released Canon R bodies falling from the sky. I figure some EOS RPs will be dislodged from their owners and hitting the used market. I did not go the online route and chose instead to watch my local camera shop’s Craigslist page. And then last week it happened and th etrade was on.
Is it good. Yes. Yes, it is. While I understand it is a new lens formula it is a faithful update of the earlier DSLR lens. With that I will start this review by copying/pasting/updating my earlier comments on that lens that apply here as well.
- Build. This lens is made of higher grade plastics than the Sony FE and is a solid feeling and visually fetching lens.
- Instead of the EF variant’s AF/MF switch the RF version has a switch that toggles the function of the control ring between Focus and Control (Where you can program it for many different purposes in camera such as ISO, aperture, shutter speed, etc.).
- IQ. No surprises here. One of the best 50mm lenses I have ever used. Better than the FE in every way in my experience.
- Great bokeh.
- Sharp.
- Great color.
- Great in low light.
- Focus speed and accuracy. Like the EF this RF variant is accurate and zippy. All focus modes work flawlessly including Eye AF.
- One new thing I noticed is that this RF lens focuses noticeably if not dramatically closer that the EF version. It has a minimum focus distance of 11.8″ / 30cm (RF) rather than 13.78″ / 35cm (EF). The Sony FE 50mm option is considerably further at 1.48′ / 45cm. The Sony Zeiss 55mm option is even further at 1.64′ / 50cm.
- The RF 50mm f/1.8 STM is not only smaller than any other fast, native full-frame mirrorless AF lenses it is significantly smaller than the Prior STM lens with the EF to RF adapter. The RP is also smaller than more expensive APS-C options.


- Being full-frame mirrorless with focus peaking I can adapt legacy glass at their original focal lengths.
- Last but not least price. With all of those traits listed above they could have likely gotten away with charging near as much as the larger Nikon Z 50mm f/1.8 lens, but instead they are charging little more for the RF 50mm f/1.8 STM lens than the EF lens. And it blows the also larger and similarly priced Sony FE 50mm f/1.8 out of the water.
Some may take issue with the lack of IBIS or lens stabilization for this combination. With a bright aperture and solid high ISO performance this is not a concern for me.
Sidebar: The DSLR in the room. One might ask why not stop at the DSLR stage? The problem is size and weight. The K-1, 1Ds MkII, and D750 cameras pictured above are bricks. For some reason along with a full-frame digital sensor often came an immense jump in size and weight. Gone were the lightweight 35mm wonders like the Nikon FG or Olympus OM-10 replaced by virtual bricks by comparison. Mirrorless promised to change that, but full-frame mirrorless cameras brought few truly small and light cameras and even fewer affordable, strong performing, small, fast aperture, and lightweight 50mm lenses if any at all. As much as I enjoy using the technically superior (Especially on the video side of things.) Sony A7c in tis discussion it is ultimately let down by lens selection… or a lack of a true nifty fifty option in my opinion… and also a bit by ergonomics when directly compared to the RP if I am completely honest. And if stills are primarily your thing the RP’s shortcomings can be easily forgiven when considering the lower cost (nearly half) and ergonomics mentioned. The closest Sony comes performance and IQ wise would be an A7c combined with a Sony Zeiss 55mm f.1.8. A combination that would ring in at almost three times the cost here. Even looking at all contenders, including other EOS R options, I argue that the only full-frame mirrorless camera that fully replicates that film SLR feel in hand and value proposition for stills is the EOS RP and RF 50mm f/1.8 STM. And I saved even more by purchasing the EOS RP used as folks migrate to the newer bodies. And we are back in 3, 2, 1…
This lens is a real winner. And if you manage to score a good deal on an EOS RP it is quite a good deal that also gives you a camera and lens combination that is reminiscent of film SLRs.
Ongoing sample gallery here. Well done Canon. As Canon continues to flesh out its affordable lens range with more lenses like this one, the 35mm f/1.8, and 85mm f/2 and third party manufacturers flock as they did to Sony they will prove to be a full on full range full frame mirrorless alternative accessible to all.
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