Sony 20mm F2.8 Review | A Compact Pancake Lens

Ahh, pancake lenses. Every manufacturer offers at least one of them, typically for their APS-C lineup of cameras, and Sony is no different.

First introduced alongside the original release of the a6000, the Sony 20mm F2.8 is the company’s attempt at producing an ultra-small and ultra-portable wide-angle lens.

Now, almost a decade has passed since the release of this lens, and we’ve seen numerous small lenses get introduced since then (mostly by third-party manufacturers), so how does this old pancake hold up these days?

Is it still worth buying even now in 2023? Let’s talk about it!

Looking for a quick summary before jumping in?

Summary/TLDR
Sony 20mm F2.8

- Incredibly compact pancake lens

- Easily pocketable

- Decent autofocus

- Actually pretty sharp

- An awesome tiny lens

mountain in albania
Tiny pancake lenses are perfect for hiking since they barely take up any space in your bag!

Build Quality

Size & Weight

Alrighty, let’s start this review off by talking about the most important factor of this lens: the size and weight.

I can honestly say that, without a doubt, this is by far the smallest and lightest lens I’ve ever used, which is really saying something because I’ve reviewed a lot of tiny Chinese manual lenses over the years. Seriously, this thing really is a pancake. Heck, I’d wager that it’s thinner than an actual edible pancake!

Ok, sorry for the tangent. Let’s talk numbers. The Sony 20mm F2.8 weighs a measly 2.4oz (69g, nice) and measures an extremely diminutive 0.8in (20mm) in length. This is mind-bogglingly small.

In most of my reviews, I talk about whether or not a lens easily fits into my camera bag or my pocket. I don’t think I need to tell you that this one does… with plenty of room to spare. It feels like a toy on my a6k.

Is the lens well-built?

Alright, so it’s literally the size of an actual pancake (like the kind you eat), but is it well-built?

The answer is: somewhat. Since the lens is so small, there’s not really any heft behind it, which can diminish the sense of a “durable feel”.

Lens Barrel

That being said, the materials that it is made out of still feel pretty good.

The lens isn’t metal by any means, but the plastic used feels fairly high quality. I’d wager it’s likely made out of the same material as most other APS-C Sony lenses of that era.

Accessories

Lens Hood

As far as accessories go, don’t expect a big lens hood.

The lens (if purchased new), will ship with a tiny, tiny hood. Like, it’s barely a hood, but it does do the job at protecting the front element.

Lens Caps

The lens, of course, comes with standard front and rear caps.

Nothing too interesting here, just your typical plastic caps. Pinch on the front, slide/thread for the rear.

Weather Sealing

As for weather sealing, don’t expect anything out of it.

If this lens did offer any sort of weather sealing, I highly doubt it would be as small or light as it is.

Built to last?

So, is the lens built to last? Honestly, I’d say so.

Although it’s small and can feel a bit flimsy due to its low weight, the lens is still built to the standard of any other Sony glass. That is to say: very good.

I have no doubts that this little thing will continue to survive for years to come. Just don’t knock it around too much or take it out into the rain.

Ergonomics

In all my reviews, I tend to touch on how the ergonomics of the lens feel. Are the buttons clicky, does the focusing and/or zoom rings work well, etc.

This thing, to be honest, is way too small to even talk about that. I mean, you can’t even get a grip on the barrel. It’s so light that you won’t even feel it on the front of your camera.

There’s not really much to talk about with ergonomics because, to be frank, you barely even have a lens attached to your camera when using this thing.

Aesthetics

As far as aesthetics go, it looks like any other pancake lens.

That is to say, very tiny, without much fluff. The barrel is a nice sleek black, and I find that it actually looks pretty cool on my a6k. It almost gives me a vintage rangefinder vibe.

beach in albania

Image Quality

Sharpness

Alright, so I’ve sung the praises of this lens for being so tiny and light, but how does it perform in terms of sharpness?

Just a quick warning: my tests don’t tend to get very scientific, I mostly just pixel peep, so don’t expect MTF graphs or anything too complex.

Wide Open

To start, when shooting at F2.8, the lens performs… well enough.

Wide open, expect fairly sharp centers, but with substantial fall-off near the corners. Performance here is, to be honest, actually still better than I expected. I looked at this lens and thought, “there’s no way this little thing is going to take decent pictures”.

Stopped Down

When you start stopping down the lens, that’s where it really starts to show its true colors. F5.6 and F8 are fairly sharp, but it really comes alive at F11.

Seriously, at F11, the entire frame is razor-sharp from edge-to-edge. It’s not quite on the same level as the Sigma lineup, of course, but it vastly exceeds any APS-C zoom lens, at the very least.

I am, frankly, blown away by how sharp it is. I know it sounds like I’m singing the lens’s praises, but I didn’t expect a pancake to perform so well.

Optical Quirks & Flaws

Anywho, sharpness is way better than I expected, but how does the lens perform when it comes to distortion, CA, etc.?

Distortion

First off, we see a little bit of barrel distortion, but not enough to be a dealbreaker.

The distortion is largely fixable in post-processing (one click in Lightroom). It may present some issues when shooting straight lines (such as architecture) but it’s largely unnoticeable otherwise.

Vignette

In terms of vignette, we see some moderate darkening of the corners when shooting wide open.

Stopping down, however, remedies this and, of course, a vignette is easily fixable in post.

Chromatic Aberrations

As for aberrations, the lens does suffer from a bit of CA. In extreme tests (branches against a sunny sky), I noticed a lot of purple fringing.

In most cases, however, it’s still minor enough to where it should be easily fixed in Lightroom.

Flaring

Finally, let’s talk flare resistance. Given the fact that this lens hardly has any sort of lens hood, it suffers from a lot of flare.

When shooting into direct sunlight, expect some major ghosting and loss of contrast. Try to avoid shooting into the sun whenever possible and you should be fine.

Overall Optical Performance

Overall, the Sony 20mm F2.8 blew me away in terms of optical performance.

I’ve always had a bit of a stigma against pancake lenses, assuming that in order to achieve their small size optical quality had to be sacrificed. That’s clearly not the case here.

This little thing can’t match a “real” lens, sure, but it punches above its weight.

Already interested in checking it out?
Sony 20mm F2.8
The Sony 20mm F2.8 offers surprisingly strong optical quality despite its small size.
mountain in albania
Despite the heavy flaring and CA, overall optical performance was quite respectable.

Focusing System

Alrighty, now let’s focus on focusing (see what I did there?).

Autofocus

Stills AF

For stills autofocus, the lens performs pretty well, offering fairly quick (and fairly accurate) focus in good conditions.

Given that the lens is a bit older, it can suffer from some hunting issues in low-light, however.

When it comes to Sony’s excellent focus assists, the lens plays quite well with EyeAF and AF-C (subject tracking). No issues there.

Video AF

For those thinking about using this lens for video, you’ll be happy to know that the focusing is completely quiet and there’s no breathing.

Video AF, while not on the same level as a newer lens, is still quite fast and very reliable. No complaints from me there. If you’re looking for a discreet and lightweight wide-angle to add to your video kit, the Sony pancake might be a good option for you.

Manual Focus

Now, for those who prefer to manual focus, how does it feel to practice MF on this tiny thing?

Well, in case it’s not obvious, the focusing ring is comically tiny. Seriously, good luck spinning it.

Anyway, manual focus is decently well dampened but, given that the lens is focus-by-wire, there are no hard stops. So, overall, usable but not great.

Other Notes

Finally, just a few more random notes about the lens that I’d like to cover.

Stabilization?

Does the Sony 20mm F2.8 have stabilization? As you’d expect, nope.

Adding stabilization will always add a bit of heft and size to a lens, so I’m not surprised that Sony opted to forego it with this.

Weird Attachments

Now, the last thing we need to cover is something rather weird: this lens has optional attachments. Or, it used to at least.

Unfortunately, I haven’t been able to find them on Amazon, but there was a point where Sony used to make two attachments for this lens: a 0.8x ultra-wide converter and a fisheye converter.

I, personally, never got the chance to test these, but I figured I’d mention them because… it’s wacky and kind of funny.

long exposure of roundabout with car lights
Really impressed with this lens.

My Final Thoughts

Alternatives

So, before I round out this review, I do want to offer a few alternatives that still fall into the “compact lens” (anything under 1.5in/3.8cm) category.

Sony 16-50mm (Kit Lens)

The first alternative would actually be Sony’s 16-50mm kit lens. Despite being a rather versatile zoom, it still is extremely tiny (when retracted).

The zoom lens definitely won’t be able to match the optical quality of this pancake (nor does it offer an F2.8 aperture), but it’s still a pretty mighty option if you’re looking for a large focal range while still staying compact.

Sigma 19mm F2.8

Second, the Sigma 19mm F2.8. Ok, this one is kind of cheating, as it’s a good bit larger.

Still though, it’s still fairly compact, and comes pretty close to the optical quality of the Sony pancake.

Conclusion

Anyway, if you’re dead-set on having the smallest lens possible, the Sony 20mm F2.8 is actually pretty damn good.

It offers respectable sharpness when stopped down along with quick and reliable autofocus. What other lens can offer great image quality and quick AF while staying under an inch long?

If you’re interested in picking up this tiny little pancake for yourself, I’ll leave a purchase link below. Thanks for reading! 🙂

Tiny & Powerful
Sony 20mm F2.8
The Sony 20mm F2.8 offers surprisingly strong image quality and fast autofocus in a tiny compact build.
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