Adapters are BACK.. and better than ever!

[kye]

Adapters used to be a big deal...  with camcorders there were wide-angle adapters.  Then for smaller sensors there were speed boosters to try and get shallower DOF and make more use of vintage photo lenses.  Anamorphic adapters were always an option / confusing dream.

Then "everyone" went FF to get that shallow DOF, and Chinese manufacturing started giving us good quality affordable fast primes and now there seems to be an avalanche of anamorphic lenses (with recent additions including anamorphic zooms, and some even have AF now!).

Why are they "back"?

Not only can adapters take MFT cameras to beyond FF, or take S35 to FF and beyond, but they can also take FF to Medium Format and beyond as well.

The key to this is the emergence of high-quality single-focus anamorphic front adapters, and especially combining them with the new anamorphic glass or with speed boosters or with super-fast native lenses.

I realised this when I shot with the GH7 + Voigtlander 42.5mm F0.95 + Sirui 1.25x combination and realised it's the horizontal FF equivalent of a 68mm F1.5.  That's not impossible in FF terms, as there are 75mm F1.4 lenses and 85mm F1.2 lenses available, but this was only with the Sirui 1.25x adapter.  There are 1.33x, 1.35x, 1.5x, 1.7x, and even 1.8x front adapters available.  There is even a PL-to-PL 1.33x rear anamorphic adapter available.  Combining the 1.33x PL-to-PL rear adapter with the 1.8x front adapter would be a 2.4x adapter.  Not a lot of anamorphic glass over 2x!

The combinations are practically endless, and compatibility will definitely be an issue with some combinations, but the thing about adapters is they multiply your lens collection.....  If you buy an extra lens then you have an extra lens but if you buy an adapter you multiply your whole lens collection by a factor somewhere between 1-2x, depending on compatibility.

Here are couple of worked examples.

Just to get the juices going, and as a completely manufacturer supported Full Frame option, Sirui has the Venus anamorphic set, which are 1.6x anamorphics with T2.9 aperture from 35mm to 135mm, with the 1.6x giving them a horizontal crop factor of 0.625, so they're the horizontal equivalent of 22mm to 84mm T1.8 lenses.  
Add the Sirui 1.25x anamorphic adapter, which is officially part of the set, and they become 2x anamorphics horizontally equivalent to 17.5mm to 68mm T1.45 lenses.  
This isn't completely beyond normal spherical FF glass, but it's an adapter that can be used across a range of lenses and quickly change the crop-factor of these and many other lenses.

Let's go bigger..

Rokinon / Samyang have a 1.7x front anamorphic adapter specifically designed for their Cine V-AF line, which includes 35mm to 100mm T1.9 Full Frame lenses (and a 24mm T1.9 APSC lens) but with the adapter they'll be 21mm to 59mm T1.1.  Once again, these aren't impossible to find in spherical versions, but we're getting into more rarified territory.  Also remember you now have two lens sets, not one lens set with an extra lens.

Would the 1.7x adapter work on other lenses?  Not easily - it seems to have a strange proprietary mount to attach to the lenses, which have a 58mm front thread diameter.  
The Sirui 1.25x adapter is huge and has an 82mm rear thread diameter, so would work on lots more lenses.  The Blazar Nero 1.5x has a smaller 52mm rear thread diameter, and the SLR Magic Anamorphot-40 1.33x has an even smaller 40mm rear thread.  However, the SLR Magic Anamorphot-65 1.33x has a 82mm rear thread and the Anamorphot-50 1.33x has a 62mm rear thread.  I think the BLAZAR LENS 1.35x has a 77 rear thread (not sure), and the Venus Optics 1.33x definitely has a 77mm rear thread.
But, if you have the funds and really want coverage, then the Letus35 AnamorphX-PRO series (1.33x and 1.8x) seem to clamp to the outside of 114mm lenses.  Of course, they're USD2500 and up!

Let's go faster...

The Sirui 1.25x adapter claims it's T2.8, but on my MFT 42.5mm F0.95 lens it didn't soften the lens even when shot at F0.95.  Maybe it wouldn't be so good if paired with a lens faster than F2.8 on a FF sensor - not sure.  
If you took an 85mm F1.4 and attached the Sirui 1.25x adapter you'd get a 68mm T1.12 - and an 85mm F1.2 would become an 85mm F0.96!  But take the 85mm F1.2 and attach the Anamorphot-65 1.33x instead and now we're down to 68mm F0.90!!  My impression was that the FF 50mm F0.95 lenses were pretty mushy at F0.95, but with a 1.33x attached they'd be 38mm F0.71 (and probably like a drug-fuelled haze).  You could find out what an F0.71 lens looks like for only USD800 - completely doable if you're crazy enough.

If we ignore the compatibility issues, and zoom out, then here's how I think of it - front anamorphic adapters are horizontal speed-boosters you mount to the front of the lens.

• 1.25x is a 0.8x horizontal speedbooster
• 1.33x is a 0.75x horizontal speedbooster
• 1.5x is a 0.67x horizontal speedbooster
• 1.7x is a 0.59x horizontal speedbooster
• 1.8x is a 0.56x horizontal speedbooster

On FF, you can take a lens and use an adapter to boost your lenses from FF to Medium Format and beyond.  The Alexa 65 has a crop factor of 0.67 - which is within reach of these adapters.

On S35, you can use an 1.5x anamorphic adapter to get you to FF, but you can combine that 1.5x with a 0.71 speed booster to boost non-mirrorless glass to a crop-factor of 0.71, which is about 6% smaller than the Alexa 65!

On MFT, you can use the 1.33x adapter to get you to S35, or combine a 0.71x speed booster with the 1.5x adapter to get you to 0.95 - just bigger than FF!  BUT maybe you can push harder than that.  No idea!

Any discussion that puts S35 closer to the Alexa 65 than FF, or MFT larger than FF would have been unthinkable even a few years ago.

Are there caveats?  Sure.  Compatibility for one thing.  The stronger squeeze-factor adapters likely have limits with how fast you can push the aperture and perhaps on sensor size too.  I suspect that my Sirui 1.25x T2.8 adapter might only be sharp with my F0.95 lenses wide open because they're MFT lenses on an MFT sensor.  I could be wrong though.  The smaller rear diameter of some of the other options might cause vignetting on larger sensors, and maybe softer corners at larger apertures.

But lens sharpness and shallow DOF are only useful to impress paying customers and for bragging to your friends, and that's not what anamorphic is really for..  so if you're willing to stop acting like you live in a hospital, these things can open up a whole new world.

[Ty Harper]

Right now I'm mostly using the Canon's .71x speedbooster on my R50V - but before that I was using it with my R5C for years as a great way to access the cam's 2-5K RAW features (which are only available in s35 mode) while basically making it FF. It's just one of the many reasons the R5C remains one of the most versatile releases in Canon history. 

[kye]

10 hours ago, Ty Harper said:

Right now I'm mostly using the Canon's .71x speedbooster on my R50V - but before that I was using it with my R5C for years as a great way to access the cam's 2-5K RAW features (which are only available in s35 mode) while basically making it FF. It's just one of the many reasons the R5C remains one of the most versatile releases in Canon history. 

Nice.

In a sense, the fact that lots of modes on FF cameras have an APSC crop is a bit of a blessing in disguise.  Not only to get a RAW file without insane resolution / bitrate, but it means that there are speed boosters for FF mounts.

I think @Andrew - EOSHD has investigated speedboosting Medium Format lenses onto FF sensors, but my impression was that it's probably a difficult architecture to find combinations of equipment that won't vignette heavily or perform poorly at fast apertures.  

This is where the front anamorphic adapters can be useful, as I'd imagine there would be far more usable configurations from fitting a front anamorphic adapter to a FF camera + FF lens combo.  The front adapters don't care about your camera mount / flange distances / lens mount / lens rear protrusion / etc, so in a way they're more like PL glass which you'd be able to keep and use regardless of what cameras you got in the future.

[maxJ4380]

On 1/2/2026 at 8:30 PM, kye said:

 

Why are they "back"?

 

3 reasons i suspect, 

1) There's a dollar in it.

2) Pretty much every influencer has been selling these and other products and their souls as well.

3) Taking a slightly less cynical view, digital cameras being "digital" these lenses may take that edge off and they give you a different field of view as well as some unique character you may or may not like. But you know all of this already.

Personally, i'm pretty happy with my sirui 24mm on mft mount. Its taken awhile to get used to it and i think i'm about 80% there. I do like the flares, i don't think their overdone. bokeh is kinda meh buts its not a 2x squeeze so to be expected, but i could insert an oval shape if it bothered me more and then there's trades off's as well. Mostly i just like the convenience i think.  Attach lens to camera and shoot. A single-focus anamorphic front adapter sounds simple but would add complexity i think, something i'm not keen on at the moment. 

I could be wrong but wasn't 1.33 tailored towards mft ? and the bigger squeezes to  s35 and full frame sensors? thats the impression i have about the different sensors sizes and squeeze ratios. 

 

[kye]

13 hours ago, maxJ4380 said:

3 reasons i suspect, 

1) There's a dollar in it.

2) Pretty much every influencer has been selling these and other products and their souls as well.

There's only a dollar in it if someone finds it to be useful or desirable in some way.  If you think otherwise, please PM me about discount codes for my all-you-can-eat gravel and building rubble buffet!

13 hours ago, maxJ4380 said:

3) Taking a slightly less cynical view, digital cameras being "digital" these lenses may take that edge off and they give you a different field of view as well as some unique character you may or may not like. But you know all of this already.

My experience with both my Sirui 1.25x adapter (and even my no-name-brand M42-MFT speed booster) is that there is no visible softening from them.  This is my experience on MFT at least, and while I don't shoot with hospital lenses, I sure went pretty deep when testing these - shooting full-resolution RAW and doing direct A/B comparisons at all F-stop values of my sharpest lenses and pixel-peeing at large zoom-in-post levels.

The Sirui 1.25x only flared a couple of times in the 6+ hours I spent shooting with it at night in the streets of Hong Kong and China, and the flares that did happen only happened when the headlights from the vehicles hit the lens directly at exactly the right angle, so the vehicle is driving straight towards me and headlights were in-frame and not flaring, then the vehicle turns slightly / hits a slight bump in the road and the angle hits exactly right and it flares for literally only a few frames, then afterwards the vehicle is still driving towards me and in frame with the headlights still shining almost directly into the camera but the flare is gone.  I went frame-by-frame trying to find a good frame to grab to show off the horizontal streak, but it was barely perceptible in a still frame, I can't remember if I even bothered uploading it.

Even the bokeh is almost imperceptibly stretched, which is to be expected for a 1.25x squeeze-factor is pretty low.  There is much more bokeh stretching and deformation from other lens factors that are present in spherical glass (cats-eyes or swirl etc).

All those add up to me just thinking it's a horizontal-only speed booster, and an economical one at that...  The cheapest Metabones speed boosters are 0.71x and USD399 and are for a specific camera-mount/lens-mount combination, the Sirui is effectively a 0.8x horizontal speed booster that can be used on practically any lens of any mount with any camera essentially forever.

13 hours ago, maxJ4380 said:

Personally, i'm pretty happy with my sirui 24mm on mft mount. Its taken awhile to get used to it and i think i'm about 80% there. I do like the flares, i don't think their overdone. bokeh is kinda meh buts its not a 2x squeeze so to be expected, but i could insert an oval shape if it bothered me more and then there's trades off's as well. Mostly i just like the convenience i think.  Attach lens to camera and shoot. A single-focus anamorphic front adapter sounds simple but would add complexity i think, something i'm not keen on at the moment. 

It does add complexity, but only during testing.  Once you have tested it on your lens collection and worked out which lenses you want to pair it with, it just becomes another "lens".

For example, the "lenses" that are of interest to me at the moment are:

• For daytime shooting:
  • 14-140mm zoom
  • 9mm F1.7 prime
• For night shooting:
  • 12-35mm F2.8 zoom
  • 17mm F1.4
  • Takumar 50mm F1.4 with speed booster
  • 42.5mm F0.95 with Sirui 1.25x adapter

The Sirui now "lives" on the 42.5mm and the speed booster now "lives" on the 50/1.4, so in a sense they're now just lenses in my mind.

Anyone with multiple camera bodies (or even those who only use one camera but rig it in different ways) will be familiar with having different configurations.  This is the same.  

13 hours ago, maxJ4380 said:

I could be wrong but wasn't 1.33 tailored towards mft ? and the bigger squeezes to  s35 and full frame sensors? thats the impression i have about the different sensors sizes and squeeze ratios. 

Squeeze factors and ratios are dead, but are also "back".

You're right that 1.33x was designed for 16:9 cameras, because it turns 16:9 into 2.35:1, but considering the GH5 has had open gate for almost a decade now and current Sony FF models still don't have it, saying it was designed for MFT is completely ass-backwards.

But that thinking is dead - almost no-one is shooting for 2:35:1 with a 16:9 sensor and for whatever reason can't crop the image to work around different squeeze factors.  Most people have the creative freedom to shoot whatever aspect ratios they want (look at how many people shoot open-gate on social media now) and the people who do have specific ratios they have to provide for a client are more likely to be vertical than horizontal!

It's even becoming common for projects to mix the aspect ratios within the same video.

I've been experimenting with 2:1, which I think is a really nice look.  My current project is a series of half-a-dozen videos and they all have different aspect ratios to fit with the vibe of each one.

[kye]

Actually, speaking of vertical video and open-gate, I know of at least one professional shooting low-squeeze-factor anamorphic with the anamorphic squeeze oriented vertically not horizontally, which gives them an image that is almost perfectly square.

4:3 is still an aspect-ratio of 1.33:1, so if you mount a 1.33x adapter vertically then you get a 1:1 image and can crop horizontally and vertically with the same ease.

Or, if you mount a 1.33x adapter vertically to a 16:9 sensor then you end up with a 4:3 image - essentially "adding open gate" to your camera.  Imagine how many people would pay a few hundred dollars to do that!

Yet another thing that these adapters can do.

Being able to wrap your head around the math involved in combining sensor crop-factors, sensor readout aspect ratios, anamorphic squeeze factors, speed booster factors, lens focal length equivalence, and aperture equivalence, really is a super-power in todays camera market.  

[maxJ4380]

2 hours ago, kye said:

There's only a dollar in it if someone finds it to be useful or desirable in some way.  If you think otherwise, please PM me about discount codes for my all-you-can-eat gravel and building rubble buffet!

 

I'm sure you have heard the old adage of selling ice to Eskimo's,  whether its useful or desirable is almost irrelevant, the main goal is to have you part with your money. Standard sales technique, sell the sizzle, not the sausage. There can be no greater exponent of this, than youtube at the moment.   

Full disclosure, i do consider myself to be one of the needy / slightly gullible as i sit here and count the 24 lenses from at least 4 manufactures.  There's probably more, thats just the one's i can see. Hey, everyone needs a hobby right ? 🙂  btw does that gravel, come with gravy or wine to help wash it down ?

4 hours ago, kye said:

All those add up to me just thinking it's a horizontal-only speed booster, and an economical one at that...  The cheapest Metabones speed boosters are 0.71x and USD399 and are for a specific camera-mount/lens-mount combination, the Sirui is effectively a 0.8x horizontal speed booster that can be used on practically any lens of any mount with any camera essentially forever.

 

I'm missing something here. Your using a single-focus anamorphic front adapter with a speed booster right ? Because i'm thinking  with just a single-focus anamorphic front adapter on the lens and relying on anamorphic compression as a rudimentary type of light gathering and calling it speed boosted is being quite optimistic. Also adding a speedbooster and single-focus anamorphic front adapter is going to cost you some $$

I suspect this conversation is geared towards those that have been in the game for a few years and have a selection of lenses to work with. Adding a speed booster and single-focus anamorphic front adapter to the mix is pretty much next level for anyone just getting started. You'd really want to be confident in the look your going after i reckon. 

5 hours ago, kye said:

But that thinking is dead - almost no-one is shooting for 2:35:1 with a 16:9 sensor and for whatever reason can't crop the image to work around different squeeze factors.  Most people have the creative freedom to shoot whatever aspect ratios they want (look at how many people shoot open-gate on social media now) and the people who do have specific ratios they have to provide for a client are more likely to be vertical than horizontal!

 

  

I'm that guy in the 4th lane doing it all wrong then... Personally i feel the whole tiktok, instagram, social media thing is a fad anyway. Mostly designed to dumb things down for those with a short attention spans and if you didn't have one before you will after..  I pity those those that watch their mobile in a vertical format. Here's a tip turn it 90 degrees, you'll probably double your field of view and widen your mind.   😉

I don't mean to be condescending but the whole vertical thing only works on a mobile phone held vertical right?  Which is kind of a small market when you compare ipads, tablets, laptops, desktops, tv's are all 16/9.  Although calling smart phones a small market might be doing it a bit of a disservice.. 

I find the whole turn anamorphic 90 degrees to shoot for vertical sounding a little gimmicky to me. I presume there are those who want the vertical format to be the next big thing, which means more tech to sell that influencers can flog through their affiliate links.. because you need this.

It also wouldn't surprise me to find that shooting anamorphic in the vertical format and stretching it makes for a nicer image, thats easier to sell to our brains. It works with a horizontal stretch, so i figure it might work in the vertical as well, Bizarre thought i know, but there it is.

6 hours ago, kye said:

Squeeze factors and ratios are dead, but are also "back".

You're right that 1.33x was designed for 16:9 cameras, because it turns 16:9 into 2.35:1, but considering the GH5 has had open gate for almost a decade now and current Sony FF models still don't have it, saying it was designed for MFT is completely ass-backwards.

 

Squeeze factors or ratios never died, never went anywhere, never even had a holiday, they have been doing exactly what they were designed to do, whether that is on mft, s35 or full frame or cinema.  If you bought a 2x anamorphic, the only realistic thing you can do is apply a 2x de squeeze. Quite literally nothing else will work and look good. 

 I like to look at the industry standard squeeze ratios as guide lines, boundaries that define a standard that most people find pleasing. Once you go past that, everything else seems a little gimmicky to me and theres science to back me up on this.

 

[kye]

16 hours ago, maxJ4380 said:

I'm missing something here. Your using a single-focus anamorphic front adapter with a speed booster right ? Because i'm thinking  with just a single-focus anamorphic front adapter on the lens and relying on anamorphic compression as a rudimentary type of light gathering and calling it speed boosted is being quite optimistic. Also adding a speedbooster and single-focus anamorphic front adapter is going to cost you some $$

I suspect this conversation is geared towards those that have been in the game for a few years and have a selection of lenses to work with. Adding a speed booster and single-focus anamorphic front adapter to the mix is pretty much next level for anyone just getting started. You'd really want to be confident in the look your going after i reckon. 

I think this is the crux of what I'm trying to say.

Anamorphic adapters ARE horizontal-only speed boosters.  
Let's compare my 0.71x speed booster (SB) with my Sirui 1.25x anamorphic adapter (AA).

Both widen the FOV:

• If I take a 50mm lens and mount it with my SB, I will have the same Horizontal-FOV as mounting a (50*0.71=35.5) 35.5mm lens.  This is why they're called "focal reducers" because they reduce the effective focal length of the lens.
• If I take a 50mm lens and mount it with my 1.25x AA, I will have the same Horizontal-FOV as mounting a (50/1.25=40) 40mm lens

Both cause more light to hit the sensor:

• If I add the SB to a lens then all the light that would have hit the sensor still hits the sensor (but is concentrated on a smaller part of the sensor) and the parts of the sensor that no longer get that light are illuminated by extra light from outside the original FOV, so there is more light in general hitting the sensor, therefore it's brighter.  This is why it's called a "speed booster" because it "boosts" the "speed" (aperture) of the lens. 
• Same for the AA adapter

Where they differ is compatibility:

• My speed booster has very limited compatibility as it is a M42 mount to MFT mount adapter, so it only works on MFT cameras and only lets you mount M42 lenses (or lenses that you adapt to M42, but that's not that many lenses)
• My Sirui adapter can be mounted to ANY lens, but will potentially not make a quality image for lenses that are too wide / too tele, too fast, if the sensor is too large, if the front element in the lens is too large (although the Sirui adapter is pretty big), and potentially just if the internal lens optics don't seem to work well for some optical-design reason

The other advantage of anamorphic adapters is they can be combined with speed boosters:

• I can mount a 50mm F1.4 M42 lens on my MFT camera with a dumb adapter (just a spacer essentially) and get a FF equivalent of mounting a 100mm F2.8 lens to a FF camera
• I can mount the same lens on my MFT camera with my SB and get a FF equivalent of mounting a 71mm F2.0 lens to a FF camera
• I can mount the same lens on my MFT camera with my AA and get a FF equivalent of mounting a 80mm F2.24 lens to a FF camera (but the vertical FOV will be the same as the 100mm lens)
• I can mount the same lens on my MFT camera with both SB and AA and get a FF equivalent of mounting a 57mm F1.6 lens to a FF camera (but the vertical FOV will be the same as the 71mm lens)

So you can mix and match them, and if you use both then the effects compound.

In fact, you'll notice that the 50mm lens is only 57mm on MFT, so the crop-factor of MFT is converted to be almost the same as FF.  
If instead of my 0.71x speed booster and 1.25x adapter, we use the Metabones 0.64x speed booster and a 1.33x anamorphic adapter, that 50mm lens now has the same horizontal FOV as a 48mm lens, so we're actually WIDER than FF.

What this means:

• On MFT you can use MFT lenses and get the FOV / DOF they get on MFT
• On MFT you can use S35 lenses and get the FOV / DOF they get on S35 (*)
• On MFT you can use FF lenses and get the FOV / DOF they get on FF (**)
• On S35 you can use S35 lenses and get the FOV / DOF they get on S35
• On S35 you can use FF lenses and get the FOV / DOF they get on FF (*)
• On S35 you can use MF lenses and get the FOV / DOF they get on MF (**)
• On FF you can use FF lenses and get the FOV / DOF they get on FF
• On FF you can use MF+ lenses and get the FOV / DOF they get on MF (***)

The items with (*) can be done with speed boosters now, but can also be done with adapters so anamorphic adapters give you more options.

The items with (**) were mostly beyond reach with speed boosters, but if you combine speed boosters with anamorphic adapters you can get there and beyond, so this gives you abilities you couldn't do prior.

The item with (***) could be done with a speed booster there aren't a lot of speed boosters made for FF mirrorless mounts, so availability of these is patchy, and the ones that are available might have trouble with wide lenses.

One example that stands out to me is that you can take an MFT camera, add a speed booster, and use all the S35 EF glass as it was designed (this is very common - the GH5 plus Metabones SB plus Sigma 18-35 was practically a meme) but if you add an AA to that setup it means you can use every EF full-frame lens as it was designed as well.