More thoughts on the Canon RF 85mm f/2 STM.

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I did not expect to like this lens as much as I do.

I did not expect to buy this lens.

It was the one lens of the three fast prime STMs I ended up with (35mm and 50mm were familiar to me) where I had no history.

But then I tried it.

Done deal.

I had my theories about why I liked it so much. Having to do with it being a compromise between the Rokinon/Samyang 85mm f/1.4 and the Pentax 100mm f/2.8 WR Macro I had. Best I could figure. Having all three made no sense so trade happened. Had my concerns, but I do not miss the Rokinon/Samyang or the Pentax. But after further thought I do not think either of those lenses are the one that really compares. The Canon 85mm f/2 does not feel in any way to be a compromise compared to the lenses just mentioned. It actually reminds me of another lens I really, really liked.

The APS-C Sony mount Sigma 56mm f/1.4 Contemporary.

sigma Contemporary 56mm f/1.4

I only sold it because I had decided to move to full frame cameras only. As much as I liked it the lens did not warrant hanging on to a camera in isolation. I liked it so much that I compared it to a full frame portrait lens.

85mm Full Frame/56mm APS-C

Why did I like it so much? Or more pointedly for the purposes of this post what traits does it share with the Canon 85mm? And why do I feel the Canon is a bit better? Well I am about to tell you.

Size and weight.

The Canon is larger than the Rokinon/Samyang mentioned above but relative to the sensor and camera bodies involved both are of a very reasonable size and weight. Very reasonable compared to higher spec’d and also larger and heavier options.

But considering that the Canon also includes IS and is made for full frame that easily makes up for the size difference.


The Sigma usually goes for $479 and the Canon is a bit more at $599. They are both relative values.

But considering that the Canon also includes IS and is made for full frame that easily makes up for the price difference.

Optical Specs

When accommodating for focal length and aperture equivalence they are virtually identical. As says:

“Your “56mm f/1.4” lens will look like a 85.68mm f/2.14 on a “APS-C” sized sensor.”

Close Focus

One thing I noted in my Sigma 56mm write up was my appreciation for its ability to focus closer than most other portrait lenses I had used.


Canon goes one further by offering actual macro capabilities.

RF 85mm f/2


Check (Sigma)…


…and check (Canon).

rf 85mm f/2

Sharpness and Colors

Check (Sigma)…

Sigma 56mm f/1.4 DC DN Contemporary Lens

…and check (Canon).


AF Speed and Accuracy

Both focus swiftly and accurately. Both are also silent while they are at it,

Low Light


Sigma 56mm f/1.4 DC DN Contemporary Lens



But in all honesty the Canon cleans up here. The Sigma was just fine, but I am quite astonished as to how well the Canon lens performs in low light. Here is another just because.


And significantly both are great for…



Sigma 56mm f/1.4 DC DN Contemporary Lens


Also taken in low light.

Having said all of that I tried to keep this pretty even, but the more I think about it the Canon is better.

  • All other things being equal a factory lens is preferred.
  • In lens IS is quite handy when dealing with bodies that do not have IS like the a6100 I had and the EOS RP. This also allows for much better low light performance.
  • I’ll just say it. Canon colors. I shoot RAW which closes the gap regardless of brand sensor wise, but I must admit I have never seen colors out of the Sigma lens like the colors I get out of this Canon lens.
  • As mentioned above at only about $120 more for a full frame lens with other features like AF/MF and macro the Canon is really the better deal.
  • Hit rate. I had the Sigma for quite a while and I got some shots I really like. But the Canon is just a no effort keeper machine.
  • And once again full frame. As mentioned above all things being equal I will take a full frame set up every time. And as good as the Sigma 56mm is it cannot fight physics.

I still say that Sigma really delivered the prime lens goods for Sony crop cameras…

…and because of them I kept Sony crop cameras much longer than I would have otherwise. But I prefer the Canon STM lens trio that has replaced them since.

RF Blog Post Product Shots

Not only does the 85mm compare well to the Sigma 56mm, but the others compare well also. While not as wide as the Sigma 16mm the Canon 35mm counters with macro capabilities, IS, and fantastic image quality. And lastly I much prefer the Canon 50mm STM f/1.8 over the Sigma 30mm f/1.4. This is no small feat since I really like the Sigma 30mm. May create a write up like this for these two lenses, but the Canon 50mm surpasses the Sigma 30mm in near every measure that matters to me. All while also being significantly less expensive.

Back to the main topic lens. Often times I purchase a lens and while initially impressed time will pass and usage will dwindle. That has not been the case here. The Canon 85mm f/2 has seem more and more use the longer I have had it.

Well done Canon.

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