Is it Hip to be Square ? – Nons SL660 First Impressions

My Nons SL660 Instax Square SLR actually arrived 2 weeks ago. Literally as I was packing to go to Canada so reviewing this camera had to wait. But I’ve now shot a few film packs and I’m impressed. It is a game changing camera but with some issues.

Nons changed the game a few years back with their SL42 theri first instax (mini) SLR. Not only was this and it’s Mark II sister an absolute game changer for instant photography. But it showed that you could still make a interchangeable lens SLR. Right when Canon and Nikon stopped making the last of the 35mm ones.

But the Instax mini versions despite their size gave mini images. they also were plasticky. But Nons have gone bigger and better giving us a part metal body and Instax Square.

Nons also continue to gradually improved the cameras over the years. And for the Tl:dr this is the best one they’ve made yet. But it is far from perfect.

Reflected selfie. Nons SL660/ Instax SQ. 2022
Nons SL660 with auto Pentacon 1.8/50 Multi coating and instax square. 2022. taken +1 to meter values

So What does the Nons SL660 bring to the Party ?

The headline is this is the world’s first integrated Instax Square SLR that accepts interchangeable lenses. Although it shares some innards with it’s instax mini predecessors, it is much better made. With an anodised aluminium alloy front body with much more care and detail than the SL42.

And it does look gorgeous if a bit bulky in black finish with a wood thumb grip. The front mounted shutter button is unscrewable and has a cable release point underneath. At 885 gms sans lens on my scales (nons say 850gms) it’s pretty heavy. My nikon FE weights 590gms for comparison. But it is much less than a Kiev 6C TTL medium format SLR (1.5Kg),

Subway.Nons SL660 + instax SQ. 2022
A little soft here especially as you head off centre. This may be due to infinity focus issues but was taken with either f/8 or f/5.6. The camera weight may have impacted too as dropped shutter to 1/125. As metered. Nons SL660 with Auto Yashinon-DS 50/1.9 on Instax SQ. 2022. Note poor exposure latitude of instax from bright shop sign to darker flower beds etc.

Bigger but better

It’s bigger and heavier than its predecessor but not as wide oddly due to changes with the mirror mechanism. Not quite in Medium format SLR territory but not far off. Like the SL42 instax frames are ejected on the right side as held with the index strip in that orientation.

Nons SL660 in comparison with Nons SL42 Mk II and a Canon EOS 3000V.
Nons SL660 (l) in comparison with Nons SL42 Mk II and a Canon EOS 3000V (r).

The attention to detail is much better. this feels much more robust and though over. The wood hand grip is a nice touch and typical of the thought poured in here. The rear is plastic but feels better as are the various controls and connectors. The cocking lever feels way more natural than the SL42 ever did.

Shutter dial of the Nons SL660
Much more attention to detail with a more solid shutter speed dial and the brand embossing. Note the LCD that shows I’ve just loaded an instax pack (S) and that aperture is not possible at 1/250 (0.0). Due to a mismatch between my mobile and the LCD refresh rates you can’t see the battery indicator that is also displayed.

In the Frame ?

if you read my reviews of the early models you’ll be aware these cameras use a canon EF mount. That allows you to use pretty much any 35mm SLR lens via an adaptor. The issue is however these lenses are designed for shooting on a 35mm frame (24mm x 36mm). So with the original instax mini (frame 46mm x 62mm) version you got cropping as shown here.

Elsewhere. Nons SL42 Mk I with Pentacon 50/1.8
Nons SL42 Mk I with Pentacon 50/1.8. Dumfries 2020

That’s obviously gonna be a bigger problem for the SL660 with a 62x62mm frame size.

Nons added an optical frame extender (aka Nons Frame extender or NFE) as they did with the SL42 Mk II. Unlike that camera which had a removable NFE. This one is built in with lenses sitting on both side of the leaf shutter & mirror

As we’ll see that does add some issues. It’s also worth noting that using the NFE adds 2 stops (so you’re f/2 setting is actually f/4). This is handy as it helps a bit with the limited shutter speeds.

Dog Watch. Instax SQ with Nons SL660. 2022
Nons SL660 with auto Pentacon 1.8/50 Multi coating and instax square. 2022. +1 to suggested meter values

Under the hood of the Nons SL660


So although this is design wise a much different camera, the core mechanics remain the same. You have the same leaf shutter set up as the prior cameras. You get speeds from 1 sec to 1/250 in 1 stop steps plus B.

Now if you use instax you’ll spot Nons’ Achilles’ heel right there. Instax is a 800 ISO film with a latitude that is notoriously small (possibly +1/-2 but likely worse). This means if you’re gonna have issues if shooting in brilliant Sunny 16 sunlight. The camera pegged at 1/250 with 800 ISO film you’re gonna need to a lens aperture of f/32. Luckily as the NFE adds 2 stops here you get away with f/16. But if you want to do Bokeh shots in sunlight you’ll need to invest in ND filters.

Whilst this is an issue, I give credit to Nons for making the brave decision to limit the shutter speed. The original SL42 was intended to have a 1/500 speed. But this wasn’t accurate so Nons took the brave and right decision to limit it.

Bulb mode is limited to 999 secs (16 minutes 39secs) which actually allows you to do star light exposures.

Mirror Box in position with the Nons SL660
Mirror Box in position with the Nons SL660

Mirror movement

The mirror box slides out of the way like the SL42 before the leaf shutter opens. This explains the delay (0.05sec according to manual). The design is neater with a smaller box sliding upwards. RE-cocking the camera moves the assembly back down.

Inside Nons SL660  after shot taken.
After firing the shutter the mirror box slides up before leaf shutter opens. Recocking the camera pulls the mirror box down


So we get the same partially couple metering mechanism as the earlier cameras. When turned on the LCD shows a suggested aperture matched to the shutter speed. This is adjusted for the 2 stops with the NFE. I found it matches well when checked against clip on area meters like the Reveni.

Nons SL660 without lens
Note NFE lens element sitting in front of leaf shutter and mirror. Another element(s) can be found to the rear of these. Note the meter cell at front of pentaprism hood.

If anything it actually over exposes (camera said f/5.6 for 1/250 where as clip metering was reading f/5.6 at 1/1250). This is odd as we’ll see in results.

The meter is an area meter so suffers from all the foibles (not great with backlighting etc). Also it isn’t shown in viewfinder so you need to focus, check meter then stop down and reframe. The finder is brighter though and in good light you can meter first, stop down and then focus. However at that point you’ll like have quite a Depth of field in your view. So pin point focusing will be hard (good for selective DoF focusing however).

The viewfinder

Viewfinder of SL660 wide open
View through the viewfinder with lens wide (f/1.8 with Pentacon auto 50/1.8 multicoating) captured on smartphone. You tend to see focus screen as well as you can see bottom of shot, But good basic screen and bright even if it isn’t square. Note vignetting which suggests rear element of NFE quite important.

Nons have kept the pentaprism and Fresnel screen of the SL42 Mk II. That’s on one level a good thing as it works but weirdly it remain in the same 35mm style format. So you get a landscape not square finder.

Although the finder shows vignetting, it isn’t as evident on final images (with 50mm M42 lenses anyway)

Viewfinder of SL660 stopped down to f/11
Same position as above but stopped down to f/11 taken through viewfinder of SL660 on mobile phone. This vignetting is not evident on final images.

It is at least central and the width of the image.

Moo Trolley. Nons SL660 2022
Image with approximate view of finder marked in red. Nons SL660 with pentacon auto 50/1.8 multicoating. Dumfries 2022

Otherwise the screen although basic is fine to use.

Power, Flash & Other features

Again we have a built in battery (3200mAh Li-ion) according to Nons. This is charged via the USB C connector on rear but works with lower amp (ideally Input: DC 5V, 1A) . Nons specifically say you can’t fast charge. And they’re right it wont allow a fast charge connection (USB C to USB C with a fast charger). I’ve tried ! There is a small red line by charge point that switch to green when fully charged. The meter LCD also gives an idea of charge.

Rear of SL660
Rear of SL660. On/off switch, Charging LED, USB C point and film eject button on side.

The camera syncs at 1/250 for flash. Nons have finally sorted out flash support. So you can use older higher voltage flash units for more retro feel. That’s as well as the newer lower voltage models (aka modern dedicated units). This is a good step forward.

As mentioned the shutter button screws of to give a cable point. There is a standard tripod point. Lugs for a strap are on the non eject side of the camera. Meaning if you wanna wear a neck strap the camera dangles on its side. I get this makes sense as it avoids snagging the film eject. But I suspect this will lead to folk using a wrist grip rather than neck strap.

Lola du Jour. Instax SQ + Nons SL660. 2022
Nons SL660 with Auto Yashinon-DS 50/1.9 on Instax SQ. 2022. +1 on metering


The SL660 like it’s SL42 brethren uses a passive Canon EF mount. Ironically you can’t use EF or EF-S lenses here. You need a mechanically movable shutter but you can in theory mount most other 35mm SLR lenses.

The EF mount has one of the widest flange diameter allowing to use other lenses via adaptors. This ironically includes adaptor that can mount Nikon F G subtype lenses with an adaptor that has aperture control. Although I would personally avoid as Nikon to EF adaptors are notoriously tight. And that’s especially so with cheaper G class plastic mount plate lens.

You can even mount some medium format lenses from Hasselblad and others.

Of course the bargain choice is a M42 adaptor as M42 lenses come in wide range (and price range). From funky bargains to legendary Pentax and German optics.

Nons SL660 in use

Once charged up I’d load the camera with metering turned on. It isn’t an issue out of the box. But when you reload the camera must be on for the shutter count to reset at loading. Otherwise you are stuck showing 0 shots.

With the camera turned on you obviously need to eject the cover sheet before shooting. Do this with the camera on and by holding down the eject button . This needs to be held for a little bit which is good as it avoid accidentally ejecting blank images. When ready to shoot make sure the camera is cocked (you should be able to see through viewfinder0. If not move the cocking lever down on the front. Focus your image. Check you there metering for given shutter speed on meter (but see below in results for adjusting). Then set your aperture and reframe/refocus and shoot. With the camera on eject your shot and repeat.

Cocking lever side of the Nons SL660
Much improved cocking lever now moves down and is better built and smoother. Note the strap lugs.

Although heavy the camera feels natural held two handedly in the landscape orientation of the viewfinder. This may be an issue for your final results. As it means your intax shot will have the white tab on the side of images. This may be an other reason why the strap lugs hold the camera with eject side down. This gives images with that strip on the bottom.

On Test

I stuck to 2 reliable 50mm M42 lenses. The budget swirl Bokeh os a Pentacon auto 1.8/50 Multicoating and a rarer Auto Yashinon-DS 50mm f/1.9. Image are scanned by my new HP MFD (apols the Pentacon ones are low res).

Results are going to be different with other lenses (duh). Expect more vignetting with telephotos. Nons say this becomes an issue with lenses above 58mm but they are still usuable.

Results – Instax is a Fickle Mistress

It’s important to note that instax is (a) quite temperamental with exposure and (b) is not the high resolution film you are looking for. In fact instax resolves 12 lines pairs per mm. This means you won’t get any benefit scanning the image are at massive resolution. It is limited to roughly a maximal 2.2MP (1488×1488) image when scanned.

That said there is something quite satisfying about these images compared to the mini version.

Focusing and optical quality

Broadly centrally the image is as good as you, your lens and instax film lets it. The NFE has little impact with this which is good. With 50mm lenses vignetting starts as the lens stopped down. But even at f/11 and f/16 it was pretty minimal and adds to the aesthetic.

Sleeping dogs. Nons SL660 on instax 2022
Taken at f/5.6 (as meter suggested) very little vignette evident. Nons SL660 with auto Pentacon 1.8/50 Multi coating and instax square. 2022

Images are a little softer to the edges than i would have expected for both lenses. It’s hard to be clear of the source. We’re seeing some of the field that was never intended to bee seen when mounted on a 35mm camera. And then there the impact of the NFE lenses. It’s not bad and I’d suggest this is a camera more suited to portrait/still life work than landscapes/architecture.

I tended to find long shots softer too. That might be to do with my failing eyesight. But the subtle differences in flange distance may add to that too as well as the NFE. The adaptor you use may also have an impact if it’s too wide.

Distortion issues

The NFE does affect radial distortion. But that depends on the lens. Take Auto Yashinon-DS 50/1.9. From reviews and sample image this has very little radial distortion on M42 bodies or on Canon dSLR. But you do get a mild degree of pincushion distortion. Not bad but more noticeable than when used natively.

3 pots. Nons SL660 on Instax Sq 2022
My shelves do not curve like that. Nons SL660 with auto Pentacon 1.8/50 Multi coating and instax square. 2022

The Pentacon has much more pincushion distortion. The lens is known to have some barrel distortion when used normally. You can see this with SL42 image earlier with no NFE optics.

Exposure – a story of 2 lenses.

My first shot using the Pentacon lens came out like this using the meter recommended speed.

Morrisons. Nons SL660 on Instax SQ 2022
As metered on Nons SL660 with auto Pentacon 1.8/50 Multi coating and instax square. 2022

Truth be told it was actually my 2nd shot. I took the same shot but forgot to stop down to the suggested f/8. But anyway this is a tad under exposed. Metering as I said matches clip on area meters quite well. The built in meter has a 2 stop correction for the NFE.

Now that was a backlit shot and I should have corrected. But for the pentacon, I found over exposing by 1 stop helped a lot here. Take this shot of my other half’s bug.

VW as metered , Nons SL660. 2022
As metered. Nons SL660 with auto Pentacon 1.8/50 Multi coating and instax square. 2022

But when I over exposed (to meter by 1 stop) I got this. Pretty much on the money. But that is a massive difference in quality for just one stop

VW +1EV. Nons SL660. 2022
+1 to metering. Nons SL660 with auto Pentacon 1.8/50 Multi coating and instax square. 2022

It was not always consistent. this still shot was near the money if slightly under exposed.

Still life on Instax SQ with Nons SL660. 2022
As metered. Nons SL660 with auto Pentacon 1.8/50 Multi coating and instax square. 2022

What’s the flash with the Yash ?

But with the Yashinon thing were more nuanced. I’d say the metering was more like a 1/2 stop out. This a nightmare with a lens with no intermediate stops.

Meter comparisons shots. Nons SL660. 2022
Top image taken +1 meter reading, bottom as per meter. Nons SL660 with Auto Yashinon-DS 50/1.9 on Instax SQ. 2022

Although you’d think the first image was one the money other shots showed a better judge with metering. Take these shots. the metered one is exactly on the mark the +1 is overblown.

Meter comparisons shots II. Nons SL660. 2022
Top image taken +1 meter reading, bottom as per meter. Nons SL660 with Auto Yashinon-DS 50/1.9 on Instax SQ. 2022

The below shot was as per metered

Lola. SL660 + Instax SQ. 2022
As metered. Nons SL660 with Auto Yashinon-DS 50/1.9 on Instax SQ. 2022

As was this outdoor shot. Again not as crisp as closer shots.

Jimmy's. SL660 + Instax SQ. 2022
As metered. Nons SL660 with Auto Yashinon-DS 50/1.9 on Instax SQ. 2022

Cost & Rivals

Nons currently want you to part with $599USD for these on pre-order. My Kickstarter one came in way less than that. It is hard to quantify that against other gear as it is such a niche product. SL42 Mk II are currently being sold at $399. But I’d now say as good as they are, I wouldn’t get one now I have a SL660.

Mint sell their InstaKon RF70 and SF70 rangefinders for a whopping $899USD. Their blinged up refurbed Polaroid SLR670 come in for more. Polaroid in the US will sell you a refurbed basic SX-70 for $389 in the US but they don’t seem in stock often.

Lomography do sell the LC-A 120 for $449USD. If you can live without instant gratification it is an incredible medium format zone focus camera with decent metering.

Final Thoughts on the SL660

This is a brilliant update to the earlier SL42 models. It is by hands down the best new analogue camera I’ve seen in the past few years. There are no real rivals to Nons SLR in the market. These are (sorry Mint & Lomography) are arguably the best Instax cameras available with a choice of optics and SLR control. The bigger format gives it a run against the legendary Polaroid SLr with their fixed lens.

Build quality is massively improved with much more appealing design. This feels much more robust and thought out. We know have wider flash support.

It works well with portrait, still life and other relatively close work.


The NFE certainly causes some issues. It may also contribute to the weaker longshot focus issues. Although that may be down to my peeps and flange issues. Despite that and even if it is my eyes the distortion which are more obvious as well as the worsening off centre focus means this sadly is not the camera for great landscape or architectural work. I get why the shutter speed is limited. But 1/250 means you will need ND filters if you wanna go all Bokeh.

And then there is the temperamental mistress known as Instax. If you’ve used any Fujifilm Instax camera you know they tend to do their best indoors with the flash on. That’s because they can accurately nail the exposure. There is almost no leeway for exposure.

That said that makes the SL660 quite a interesting challenge to master. It’s not cheap but it compares well to the cost of Mint rangefinders or Polaroid provided fully refurbed SX-70. But you are stuck with their optics.

This is bloody great camera if a bit flawed. A marked improvement over the SL42

One thought on “Is it Hip to be Square ? – Nons SL660 First Impressions”

  1. This is a lovely review. I received mine a few weeks ago and have been using it quite a lot. Couldn’t agree more with you. I had also thought that I would prefer wide to square, but this has completely changed my mind. I’m not quite sure what I’ll do if Nons released an instax wide camera…

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.