That’s some statement Dec and I value your opinion. I haven’t personally seen anything tangible in terms of output myself, if anything, some of the lens rendering has looked a bit off.
A third better than a 750, please divulge.
I should probably go into detail, so forgive me if this is long. I’m sure there are D750 users considering a switch so this may be relevant here. This is not the case of a Sony fanboy coming in to troll D750 users but intended as my objective comparison of the two bodies as far as possible. Some points will logically be subjective based on what or how I shoot.
So here we go…
I first grabbed the A7iii expecting not to like it. I'd used various A7 iterations over the years so thought that ergonomically it wouldn't be for me. I'd also heard endless talk of 'nightmare' menus. I've had various Fuji mirrorless cameras over the years which I've loved but have led me to believe mirrorless is a long way off. I also have a full Nikon system that has served me really well and helped me capture some of the best images of my life. While I'm generally not a fanboy, I am fairly brand-loyal and having shot Nikon for 11 years I would always consider their offerings first. I loved and still love the D750.
So, in short I wasn't actually being objectively fair to the Sony when I first grabbed it.
Now, in the past I've contemplated changing system only twice. Both times to Canon and both times, after testing and consideration, I didn't do it. This time was different. After a day with the A7iii we made the decision to put ourselves through the abject hell of changing camera systems.
The first thing that shocked me about the A7iii was the ergonomics. The important disclaimer here is that I'm 5ft9 and accordingly have dainty lady-hands, but it felt perfect. The grip is nicely recessed like the D750 and I didn't have the 'pinky problem' I'd had using other Sonys. Within a minute or two I was totally at ease with how everything was placed. Aperture/shutter control just like Nikon. ISO control even easier than Nikon. So the much-maligned ergonomics, for me at least, were as good as or better than my much-beloved D750. Remember the ergonomic complaints about the D750 when it came out? While the D750 kinda short-changed back-button shooters, the A7iii gets it spot on offering both dedicated AF-ON and AEL buttons on the back.
Then there's the menu system. I could see how it could be daunting at first, but I'm a geek. I quickly grew to enjoy the depth to it. Sony have left the camera pretty open to customisation so there's a lot you can change and as a result the menu is extensive. Like Nikon, though, you can assign things you'll often use to a 'my menu' type thing cutting out stuff that you won't need on a shoot. The Function menu is also brilliant, allowing you to change your most used features without taking an eye off what you’re shooting. Like the D750, once you've set it up to your tastes you shouldn't really need to go into the menu system often. The customisable buttons are utterly brilliant. In fact, pretty much everything is customisable in almost every way - this again flew in the face of my ergonomics concerns. I remember marvelling that I could assign my movie Rec button to control ISO on the D750. The Sony is next level in that regard and it's a very clever way of doing things.
Next we have the AF. I shot in good weather but from midday to near enough midnight when I first had a go on the A7iii. First is the ingenuity in the AF system - eye focusing and edge to edge tracking is just marvellous to use. I had dismissed Eye-Focus as a gimmick but it is a proper delight leaving you to concentrate more on framing. I've yet to test it, but my friend uses the face recognition control and swears by it for weddings. Basically, you take a pic of the Bride in the morning and can at any stage set the camera to prioritise her face in any large groups throughout the day. The tracking is incredible, I shot my friend backlit in evening light jumping and moving fast towards me at 10fps and it literally missed focus on 1 or 2 in 10 images. The D750 gets nowhere near it in this respect. Being able to shift your focus points right to the edge of the frame is wonderful. One of my biggest gripes about the D750 was the limited spread of AF points - especially as I'd come from a D4 which had a wider spread.
In low light I found it to best the D750 in regard to both AF and high ISO ability. I didn't find the camera hunting around for focus in light that had me shooting over 6400 ISO, unlike other mirrorless cameras (and DSLRs) I've used. In fact, eye focus was often still working accurately. In post, I found more colour depth in high ISOs than on the D750 when I compared shots side by side. The Nikon also missed focus more than the Sony in low light (it was still great though).
The D750 is responsible for making me use live view to shoot. I both loved the feature (flippy screen and exposure preview) and hated it (p***-poor AF and screen blackout). Being able to use the same incredible focus you get on the EVF to shoot in LV is a gift. Anyone who knows my work will know I love shooting from a variety of perspectives and angles (and shooting through things). Doing this on the D750 was a fight for good focus, on the A7iii it's a total joy.
In terms of IQ and lens rendering I'm more than happy. It took me 10 minutes in Lightroom to adjust my presets for Sony - it feels a lot like editing Nikon files. The Zeiss 85mm is absolutely gorgeous and the Sony 85mm FE1.8 is incredibly sharp. I also used Sony's own 55 1.8 and 35mm 1.4 which both produced lovely images and focused fast. I've gone for a Sigma art 35mm for price reasons but have yet to get it so can't comment on how it translates to e-mount. But honestly, I'm not a big pixel peeper. I often keep or sell lenses based on factors I can't readily articulate.
On lenses, for some this could be a major flaw. There simply isn’t as many lenses for the Sony as there are for CaNikon cameras, and some (not all) of the Sony glass is ridiculously expensive. That said, I know people who are happily shooting with their old Canon glass with no issues, and Sigma have made a big statement by supporting the FE mount on the Art range and offering an alternative to the pricier Sony range. Before the sigma announcement I didn’t think I’d bother to even try out the A7iii let alone consider the switch.
The buffer, a big gripe of mine with the D750 from day one, is perfect. It never once stopped shooting before I wanted to. Too many times I've found myself outside a church, covered in confetti and watching a couple kiss while cursing at my D750 that had gone on strike. 10fps is ridiculous, and should you need it the buffer keeps up with it well. Silent shooting is a godsend and now allows me to do Still Photography without a blimp, or become discreet when a wedding/event requires it. There’s also an anti-flicker shooting (though not in silent mode) - this will make it much easier for me to PP poorly lit venues.
EVFs are marmite, but I love them. No more chimping to double-check exposures - I know I’ve nailed it (and likely the focus too). The blackout is no more noticeable than on my D750 when the mirror flies up. And when in silent mode it’s actually quietly reassuring to get that flicker and know that you did actually take the shot! I recall being disappointed that the D750 didn't have focus peaking. Shooting my manual Nikon lenses on the Sony is more enjoyable than shooting them on Nikon, especially the tilt-shift because of FP. I have no issues with lag or disorientation that I’ve heard from some. And reviewing images on the EVF in harsh sunlight is helpful
In terms of battery, it’s rare that I need to use a second battery in my D750s while shooting a wedding. I’m sure the A7iii will take 2. But in saying that, the battery tech is superb considering it’s powering an EVF and screen constantly. If I heavily use my D750 screen to shoot, the battery depletes quickly. You can charge the A7iii via USB or USB-C, meaning that those big Anker battery packs or your car USB ports can top you up should you need it. USB charging in general is a great failsafe if you’ve travelled for a shoot and forgot to pack your battery charger (more on the charger later grrrr) or if you shoot destinations and want to save weight.
It does have flaws, or what could be perceived to be flaws by some. The same people who complained about the D750 body being too small (It was a criticism when it came out) will hate the size of it. Although my friend is a 6-footer with big manly, man-hands and he loves it. There’s no way to quickly turn on/off auto ISO. The clock inexplicably has no second counter so syncing 4 cameras is unnecessarily awkward - it can’t be done via software like the D750. The tilt screen can be fiddly to articulate as it doesn’t really have anything for your nails to grip onto - the D750 comes screen out much more easily. They don’t bundle a dedicated charger with it and the official one costs £70, which is pretty mean and a big PR misstep. Good third party double chargers are only £20-30 though and it is great that you can charge via USB. But the biggest gripe is there is currently no lossless compressed RAW format, which is pretty poor. Some of these issues can and really should be fixed by firmware updates if Sony bothers to listen.
So, is it 33% better than the D750? Being a big fan of the D750 and as objective as possible, I say it is easily so. I once said this about the D750 but, pound for pound, the A7iii is the best full-frame camera I’ve used. Whether you
need one as a D750 shooter is, as ever, a different question entirely.
Full disclaimer: I am not a representative for Sony or Nikon, nor do I work with either company. I buy all my gear and the only contact I have with camera companies is when something messes up. This comparison is based on my real world shooting, often side by side with the D750 for comparison. I specifically haven’t commented on weather sealing, quality control or durability of the A7iii because it’s too early for me to say how it performs. If there's significant interest, I can update findings after I start to use it on weddings.