Even the most com­pact device can be turned into a bazooka. Pho­to: academy.wedio.com

Gone are the days when pro­fes­sion­al video cam­eras were very bulky and more like grenade launch­ers — today even the high­est-end devices look like a reg­u­lar cam­era. So Sony has two com­pact mod­els spe­cial­ly tai­lored for shoot­ing video: Sony a7S III and FX3.

They are both very sim­i­lar and very dif­fer­ent: both are aimed at pro­fes­sion­al video­g­ra­phers, both are extreme­ly portable. How­ev­er, the style of shoot­ing for which they are cre­at­ed is fun­da­men­tal­ly dif­fer­ent.

Video qual­i­ty: Top-notch per­for­mance on both sides
Design: two oppos­ing approach­es
Audio: pro­fes­sion­al fea­tures
Cam­era work: find your style

Video quality: Top-notch performance on both sides

Before mov­ing on to the com­par­i­son, let’s briefly answer the ques­tion of why you might need such a cam­era at all. Quick and com­plete answer: they pro­vide the high­est qual­i­ty video that allows you to shoot high-qual­i­ty mas­ter­pieces and pro­fes­sion­al-grade com­mer­cial mate­r­i­al, as well as all the fea­tures that a hard-core film­mak­er could need.

An exam­ple of a 4K video tak­en with a Sony a7S III. Source: DSI Pic­tures Youtube chan­nel

Visu­al­ly, the a7S III and FX3 share many fea­tures and func­tions:

  • 12-megapix­el full-frame BSI CMOS sen­sor;
  • inter­nal record­ing in UHD 4K 120p 10-bit 4:2:2;
  • con­ve­nient for­mats with effi­cient com­pres­sion — XAVC SI and XAVC HS;
  • out­put of 16-bit Raw video through a full-sized HDMI port;
  • shoot­ing RAW in 4.2K 60p using the Ato­m­os Nin­ja V and V+ recorder;
  • inter­nal Full HD record­ing at up to 240p frame rate for super slow motion;
  • advanced aut­o­fo­cus with phase detec­tion;
  • 15 stops dynam­ic range;
  • wide range of ISO 80–102400 for shoot­ing in low light;
  • S‑Log3, S‑Cinetone and oth­er pro­files for col­or cor­rec­tion.

An exam­ple of a 4K video tak­en with the Sony FX3. Source: Youtube chan­nel Jason Mor­ris

If you try to choose one of these cam­eras sole­ly on the basis of char­ac­ter­is­tics, it may seem that they are exact­ly the same. This is due to the fact that they use an iden­ti­cal matrix, which is respon­si­ble for the qual­i­ty of the pic­ture. But the main dif­fer­ences between these cam­eras lie in the design and, accord­ing­ly, in how to shoot on them.

Win­ner: draw.

Design: two opposing approaches

At first glance, you can’t tell that these are pro­fes­sion­al cam­corders. Pho­to: Youtube chan­nel MPB

The dif­fer­ence in the con­struc­tion and design of the cam­eras is imme­di­ate­ly notice­able. Even the tex­ture and col­or of the body is dif­fer­ent. The Sony a7S III is a clas­sic black mir­ror­less cam­era. The FX3 fea­tures a dark gray Cin­e­ma-style exte­ri­or for film­mak­ers and pro­fes­sion­al video­g­ra­phers. A small detail, but it clear­ly demon­strates that despite the sim­i­lar char­ac­ter­is­tics, the cam­eras are designed for dif­fer­ent tar­get audi­ences.

The Sony a7S III looks like a reg­u­lar mir­ror­less cam­era with a handy swiv­el screen. Source: bhphotovideo.com

But the set of ports for the two mod­els is the same, even their loca­tion is very sim­i­lar. Each cam­era received:

  • full size HDMI;
  • USB‑C
  • Micro-USB/­Mul­ti-Port;
  • hot (or, as Sony calls it, mul­ti-inter­face) shoe;
  • 3.5mm head­phone jack;
  • 3.5mm micro­phone input.

On the oth­er side of the case, you will find slots for mem­o­ry cards. Both mod­els have two slots for fast CFex­press Type A and SD cards. A very handy fea­ture of the new Sony mod­els, espe­cial­ly giv­en the focus of our heroes on video shoot­ing.

Design pros and cons:

Clas­sic mir­ror­less cam­era focused on video Super com­pact cam­corder
Built-in viewfind­er Detach­able top han­dle with XLR inputs
A design famil­iar to all users of the a7 series Built-in thread on top of case for cage/accessories
But­tons are sep­a­rate­ly cus­tomized for video and pho­to Built-in fan
Key lay­out tai­lored for video
Mul­ti­ple record­ing indi­ca­tor lights — rear and front
Requires a cage to install acces­sories No viewfind­er
Advanced record­ing requires option­al XLR adapter
no fan

Win­ner: FX3.

Huge REC but­ton and cage holes on the FX3. Pho­to: camerajabber.com

If you plan on shoot­ing video for the most part, the FX3’s design comes with a host of ben­e­fits, includ­ing pre-cut cage threads and option­al acces­sories. The only neg­a­tive is the lack of a built-in viewfind­er. On the oth­er hand, the a7S III will be a handy option if you plan on switch­ing between stills and video, as well as shoot­ing through the viewfind­er hand­held.

Audio: professional features

Anoth­er impor­tant dif­fer­ence in cam­eras is how sound is record­ed.

Right out of the box, the FX3 looks like a clear win­ner as the cam­era comes with a ded­i­cat­ed top han­dle that hous­es two XLR inputs.

XLR inputs are required for many pro­fes­sion­al micro­phones. You can con­nect a micro­phone to each input and record the sound of sev­er­al sources at once.

There’s an option­al dig­i­tal stereo audio inter­face on the han­dle, so you’re essen­tial­ly get­ting four audio chan­nels at once. The a7S III can also work with XLR “t‑shirts”, but for this you will need to buy an XLR-K3M XLR hot shoe adapter for the cam­era.

The FX3 han­dle not only allows you to con­nect addi­tion­al micro­phones, but also makes shoot­ing from the waist as com­fort­able as pos­si­ble. Pho­to: theroco.com

Tech­ni­cal­ly, the sound qual­i­ty on the cam­eras will be the same. How­ev­er, the FX3 han­dle is much more com­fort­able in prac­tice, because you can hold on to it! And the a7S III with an XLR adapter is a few hun­dred dol­lars more expen­sive than the FX3, which comes with an XLR gad­get in the box. So if you plan to use XLR micro­phones, it makes sense to take the FX3.

Oth­er­wise, the cam­eras are no dif­fer­ent — both have a stan­dard 3.5mm head­phone jack and a micro­phone input.

Win­ner: FX3.

Camera work: find your style

Here the choice becomes more dif­fi­cult and depends on your shoot­ing style. One of the decid­ing fac­tors is the a7S III’s built-in viewfind­er, which is miss­ing from the FX3. This makes the a7S III a more suit­able cam­era for pho­tog­ra­phy. The a7S III looks like a clas­sic mir­ror­less cam­era, which means it’s per­fect­ly tuned for hand­held pho­tog­ra­phy. In addi­tion, the viewfind­er is more con­ve­nient to use on bright sun­ny days, when the screen can light up, the pic­ture in it is clear­er and more con­trast­ing. So if for some rea­son you need a viewfind­er, get the a7S III.

Anoth­er inter­est­ing fea­ture is that the a7S III is com­plete­ly “sealed” (pro­tect­ed from dust and mois­ture) as there is no fan in the cam­era. This means that it is poten­tial­ly more adapt­ed to dif­fi­cult weath­er con­di­tions. On the oth­er hand, some users of the a7S III have com­plained about over­heat­ing issues in hot weath­er.

The Sony a7S III is pro­tect­ed from dust and mois­ture, so it should sur­vive a lit­tle rain. Whether the FX3 will pass such a test is a big ques­tion. Pho­to: cined.com

Where the FX3 seems to be the favorite is in the lay­out of con­trols and cus­tomiza­tion. The cam­era is designed specif­i­cal­ly for video, so it has a zoom rock­er right on the shutter/video record but­ton, which is handy for smooth zoom­ing when shoot­ing hand­held.

The top han­dle and addi­tion­al thread are impor­tant ele­ments for a spe­cial­ized cam­corder: this allows you to shoot hand­held using addi­tion­al acces­sories. To work the same way with the a7S III, you’ll need a cage that adds extra weight.

Win­ner: draw.


In terms of the qual­i­ty of pho­tog­ra­phy, the cam­eras do not dif­fer, because they have the same matrix, proces­sor, aut­o­fo­cus and the rest of the fill­ing. But the a7S III will be clear­ly a more con­ve­nient option due to the form fac­tor, the loca­tion of the but­tons (with the pos­si­bil­i­ty of sep­a­rate cus­tomiza­tion for pho­tos and videos) and, of course, the same viewfind­er.

Win­ner: a7S III.


Video only — FX3. Also a pho­to — a7S III. Pho­to: Youtube chan­nel ZY Cheng

Both cam­eras are handy portable tools for pro­fes­sion­al videog­ra­phy. In terms of pic­ture qual­i­ty, avail­able modes and cam­era func­tions are iden­ti­cal. The choice comes down sole­ly to the body design and ergonom­ics.

Video­g­ra­phers who are not inter­est­ed in pho­tog­ra­phy should choose the FX3, as the cam­era is com­plete­ly sharp­ened specif­i­cal­ly for video shoot­ing. There is noth­ing super­flu­ous in the design, but there is a con­ve­nient han­dle with two XLR con­nec­tors. And it also has a built-in fan, so that the cam­era does not face over­heat­ing. There­fore, if you need to shoot in the sun for a long time, the FX3 looks more inter­est­ing. But if you dare to shoot in bad weath­er, then the a7S III is more like­ly to sur­vive the bad weath­er.

Over­all, the Sony FX3 is best suit­ed for long tri­pod shoot­ing — it’s good for doc­u­men­taries and events.

For those who occa­sion­al­ly take pho­tos, or need a hand­held viewfind­er at eye lev­el, the DSLR-style form fac­tor offered by the a7S III is more suit­able. Also, the a7S III is a great option for “water­ing” (shoot­ing every­thing in a row with­out a clear plan) — again, the viewfind­er and more con­ve­nient con­trols when work­ing direct­ly behind the cam­era are a plus.