Sony A1 vs A7R IV – The Key Differences

The Sony a7R IV has been a very popular choice for wildlife photographers ever since it launched back in July 2019.

I picked one up for myself not long after it hit the shelves and since then it has probably spent more time in my camera bag than any other camera that I own.

The 61 megapixel sensor in the a7R IV lets you crop closer than ever before, which if you shoot wildlife you’ll know just how valuable this cropping power can be, since you can’t always get as close to your subject as you would like to.

However, although the AF on the a7R IV is no slouch, it never matched the AF speed of the stacked sensor in the a9 and a9II, nor can it shoot at 20 frames per second with zero viewfinder blackout.

On January 26th 2021 Sony introduced a new flagship camera, the Sony a1. The Alpha 1 packs a new 50.1 megapixel stacked sensor and is able to shoot at up to 30 frames per second, along with 8k video and 4k 120.

In my Sony a1 vs a9II comparison I compared the new flagship with its predecessor. However, in this article I’ll be comparing the a1 with the a7R IV to see how they stack up.

Before we dive in, here’s a quick list of the key features that they share in common:

• NP-FZ100 battery
• 5-axis stabilization with 5.5Ev of compensation (CIPA)
• ISO 100-32000, Expanded ISO 50 to ISO 102400
• 1,440,000 dots LCD with adjustable angle (up 107 degrees, down 41 degrees)
• Multi Interface Shoe (MI Shoe) with a Digital audio interface

Key Spec Comparison

First, a quick overview of the key specs of each camera.

Specifications	Sony A1	Sony A7R IV
Sensor:	50.1 MP 35mm full-frame stacked back illuminated Exmor RS CMOS sensor	61.0 MP 35mm full-frame back-illuminated Exmor R CMOS sensor
Processor:	BIONZ XR	BIONZ X
ISO Sensitivity Stills	ISO 100-32000, Expanded ISO 50 to ISO 102400	ISO 100-32000, Expanded ISO 50 to ISO 102400.
ISO Sensitivity Movies	ISO 100-32000 equivalent	ISO 100-3200 equivalent
Continuous Shooting Electronic Shutter:	30 FPS	10 FPS
Continuous Shooting Mechanical Shutter:	10 FPS	10 FPS
Autofocus Points:	759 phase and 425 contrast detection points	567 phase and 425 contrast detection points
Stabilization:	5-axis (5.5-stops)	5-axis (5.5-stops)
EVF:	9.44 million dots	5.76 million dots
LCD:	1.4 million dots	1.4 million dots
Image Buffer:	JPEG Extra fine L: 182 frames, JPEG Fine L: 400 frames, JPEG Standard L: 400 frames, RAW: 238 frames, RAW & JPG: 192 frames, RAW (Lossless Compression): 96 frames, RAW (Lossless Compression) & JPG: 83 frames, RAW (Uncompressed): 82 frames, RAW (Uncompressed) & JPG: 78 frames	JPEG Extra fine L: 68 frames, JPEG Fine L: 68 frames, JPEG, RAW: 68 frames, RAW & JPG: 68 frames, RAW (Uncompressed): 30 frames, RAW (Uncompressed) & JPG: 30 frames
Electronic Shutter:	1/32000 to 30 sec	1/8000 to 30 sec
Mechanical Shutter:	1/8000 to 30 sec	1/8000 to 30 sec
Memory Card Slots:	Two Slots. UHS II/I SD cards and CFexpress Type A cards are supported in both slots.	Two Slots. UHS II/I SD cards are supported in both slots.
Wireless LAN (Built-In):	IEEE 802.11 a/b/g/n/ac [2.4-GHz band /5-GHz band])	IEEE 802.11 a/b/g/n/ac [2.4-GHz band /5-GHz band])
LAN Terminal:	1000BASE-T, 100BASE-TX, 10BASE-T	No
USB:	SuperSpeed USB 10-Gbps (USB 3.2) Type-C connector	USB Type-C that supports USB 3.2 Gen 1.
Dimensions (W X H X D):	Approx. 128.9 mm x 96.9 mm x 80.8 mm	Approx. 128.9mm x 96.4mm x 77.5mm
Weight:	737 g (1 lb 10.0 oz)	665g (1lb 7.5 oz)
Battery Life Stills:	Approx. 430 shots (Viewfinder) / approx. 530 shots (LCD monitor) (CIPA standard)	Approx. 530 shots (Viewfinder) / approx. 670 shots (LCD monitor) (CIPA standard)
Battery Life Video:	Actual: Approx. 90 min. (Viewfinder) / Approx. 95 min. (LCD monitor) (CIPA standard). Continuous: Approx. 145 min. (Viewfinder) / Approx. 150 min. (LCD monitor) (CIPA standard).	Actual: Approx. 90 min (Viewfinder) / Approx. 105 min (LCD monitor) (CIPA standard). Continuous: Approx. 160 min (Viewfinder) / Approx. 170 min (LCD monitor) (CIPA standard).
Price (MRRP):	$6,498.00 / £6,499.00	$3,498.00 / £3,199.00

Sensor and Processor

The biggest difference between these two megapixel monsters is the sensor. Although both cameras share a similar 35 mm full-frame back-illuminated sensor, that’s where the similarities end.

The a1 features a 50.1 MP 35mm full-frame stacked back illuminated Exmor RS CMOS sensor, whereas the a7R IV features a 61.0 MP 35mm full-frame back-illuminated Exmor R CMOS sensor.

The a1 also features a new advanced BIONZ XR engine that boosts speed by up to 8x compared with the BIONZ X engine found in the a7R IV.

The architecture of the a1’s stacked sensor and the super fast processor enables the a1 to shoot at up to 30 frames per second with zero viewfinder blackouts, whilst the a7R IV on the other hand is limited to 10 frames per second and that’s with blackouts.

Both cameras share an identical ISO range of 100-32000, and expanded ISO 50 to ISO 102400. However, early comparisons show that the a1 has improved ISO performance with less noise.

Electronic Shutter

The electronic shutter readout speed in the Sony a1 is less than 1/200th of a second. Sony has not published the electronic shutter readout speed for the a7R IV, but Jim Kasson has tested this and claims it is around 1/10 second.

The much faster shutter read-out speed means that the a1 suffers a lot less from rolling shutter than the a7R IV does when using the electronic shutter. You typically wouldn’t use the electronic shutter on the a7R IV for action shots as you would risk distorting your subject, but this is not an issue with the a1.

Continuous Shooting

With the a1 you can also shoot at up to 30 frames per second when using the electronic shutter, this compares to 10 frames per second with the a7R IV.

Flash sync with electronic shutter

With the a7R IV flash sync is limited to the mechanical shutter, but with the a1 you can make use of flash sync as high as 1/200 sec with the electronic shutter. In APS-C/Super 35 mode this increases to 1/250 sec.

These flash speeds are only possible when triggering a flash using the a1’s Multi Interface Shoe.

Flicker-free electronic & mechanical shutters

Both the a1 and a7R IV feature an anti-flicker mode that adapts to the flicker of lights when the camera detects flickering when the frequency of the light source is 100 Hz or 120 Hz.

Whereas this feature was only available when using the mechanical shutter with the a7R IV, with the a1 it’s now available when using the electronic shutter as well.

This means that the electronic shutter is now more usable when shooting under LED lights, or in sports venue that have LED signage in the background that may cause banding issues.

Mechanical Shutter

Both the a7R IV and a1 feature a mechanical shutter, but they have been some significant improvements to the mechanical shutter of the a1.

The Alpha 1 shutter curtains are now made of carbon fiber, and there’s a new dual driven mechanism that utilizes springs and an electromagnetic drive actuator has been developed to make the unit lighter and improve durability.

Anyone who owns a Sony Alpha knows that the sensors are particularly prone to attracting dust, especially when changing lenses. Thankfully with the a1 there is now an option to close the mechanical shutter to protect the sensor when the camera’s turned off, this is a feature that has been carried over from the Sony a9II with firmware 2.0.

The a7R IV does not currently support closing the shutters on power off, it would be nice if Sony did add this option via firmware update like with the a9II.

Improved Flash Sync Speed

The a1 supports a mechanical shutter sync speed of up to 1/400 sec in full-frame mode, or 1/500 sec in APS-C / Super 35 mode. The Sony a7R IV supports a maximum flash sync speed of 1/250 sec.

Continuous Shooting

Both the a1 and a7R IV support a maximum of 10 FPS when using the mechanical shutter.

Stabilization

Both cameras feature in-body image stabilization (IBIS), with the same 5.5EV of correction.

However, the a1 has one extra trick up its sleeve when shooting 4k video, and this is active Steadyshot stabilization. This basically adds digital correction on top of the in-body stabilization. Here’s an example video from Sony of this in action:

Autofocus

The Sony a1 is able to perform 120 AE and AF calculations every second. I’ve not seen any official figures from Sony on how many AE/AF calculations per second the a7R IV can achieve, but for comparison the a9II achieves 60 AE/AF calculation per second and the a7 III achieves 20 per second. It’s most likely that the a7R IV is also around the 20 per second mark.

The faster phase detection AF can work all the way down to f/22 with the a1, this compares to f/11 on the a7R IV. When these apertures are exceeded the slower contrast detection is used and the camera will only lock focus on the first frame of a continuous burst.

Both cameras feature real-time Eye-AF for humans and animals, although animals are restricted to dogs and cats according to Sony, despite many other mammals working well. But with the a1 Sony has taken this one step further by introducing support for bird Eye-AF.

The a1 features 759 phase-detection AF points in both full-frame and APS-C mode when using full-frame lenses, with APS-C lenses this reduces to 575 phase-detection points.

The a7R IV features 567 phase-detection AF points in full-frame mode and 325 points in APS-C mode when using a full-frame lens. With an APS-C lens this reduces to 247 phase-detection points.

Both cameras have 425 contrast detection AF points.

The a1 features an option to temporarily cancel AF tracking of a subject. So, if you have two subjects in the frame you can hold a button to temporarily cancel the tracking on your current subject, then switch to tracking the second subject. When you release the button tracking goes back to the first subject. This feature is not available with the a7R IV.

APS-C / Super 35 Mode

The larger 61.0 MP sensor in the a7R IV means that when you switch into APS-C / Super 35 Mode you’ll still be shooting a 26.2 MP image. This compares with 21MP on the a1.

Still Image Recording Formats

The a1 is the first Sony camera to offer the option of lossless raw. This promises smaller raw files but with all the potential editing capability of the sensor’s output. This file type option is not available with the a7R IV.

Lossless compression creates files between 20% and 50% smaller than uncompressed files, depending on the image content. However, if you still want to achieve 30 fps then you’ll need to shoot compressed RAW or JPEG, uncompressed and lossless both reduce the frame rate down to 20 fps.

Something else that the a1 offers and the a7R IV doesn’t is an oversampled 21MP mode that creates JPEG or HEIF images from the full 50MP data. HEIF images are on par with the best JPEG’s but with approximately twice the compression. With this option you can also still shoot at up to 30 fps.

The Alpha 1 also gets a new “Light” JPEG size setting that results in smaller files than the “Standard” setting.

Video

The a7R IV can record 4K video at up to 30fps and 100Mbps using XAVC S compression, and 1080p up to 120fps. It does bin pixels when shooting in full-frame mode because of its 61MP sensor. If you shoot in APS-C mode there’s no pixel binning.

The a1 trumps this by a mile by introducing 8K video and 4k 120fps. The a1 reads out a 8640 x 4860 pixel region (full sensor width) which then gets downsampled to 7680 x 4320 8K output. 8K video can be captured at up to 30p NTSC (25p for PAL users), and can be saved as 10-bit 4:2:0 XAVC HS files (H.265).

The highest-quality 400 Mbps video from the a1 can also be written to a V60-rated UHS-II SD card, so you don’t need to invest in the expensive CFexpress Type A cards to capture 8K, unless you want to shoot 4k 120p.

Both cameras support picture profiles including S-Log2, S-Log3 and HLG (Hybrid Log-Gamma), but the a1 also gets S-Cinetone which until now has only been found in Sony’s professional FX video cameras.

With the a7R IV all recording options are limited to 8-bit, both internally and over HDMI. The a1 on the other hand can record 10-bit 4:2:2 internally. The a1 also supports 16-bit RAW output to an external recorder via HDMI, although this is limited to 4k.

Here’s an example 8K video from the a1, although you’ll need an 8k display to enjoy it fully!

And here’s an example 4k video from the a7R IV:

To help keep the a1 from overheating the camera uses a similar heat dissipation design to the one developed for the a7S III. This allows for ‘more than 30 minutes’ of 8K capture according to Sony.

Both cameras support Eye AF for movie shooting and also have unlimited record times, in the past there was a 30 minute recording limit.

Viewfinder

The Sony a1 features a 9.44M dot OLED viewfinder with both a 120 and 240 fps mode. This compares with 5.76 million dots in the a7R IV and 60 / 120 fps.

The a1 also includes a new ‘Frame Rate Low Limit’ mode, which maintains viewfinder responsiveness even when you’re shooting at slow shutter speeds. With this turned on blackout frames are inserted at an appropriate frame rate to improve display response and make it easier to follow subjects without display lag.

Body and Menu

Both cameras share a very similar body and controls, but they are not identical. One difference is easy to spot, whereas others require a little more scrutiny.

The most obvious difference is that the a1 features an additional drive mode dial where you select the AF mode and shooting speed, with the a7R IV this is all done in-camera.

Now for the smaller differences.

If you look at the front of the cameras, you will see that the a1 features an IR white balance sensor which the a7R IV does not. This promises improved white balance accuracy, particularly under fluorescent, LED, or other artificial light sources.

The lens mount on the a1 has also been strengthened, and the shutter now closes when the camera is turned off. The a1 also has a slightly larger movie start/stop recording button.

The memory card door on the a1 features a new slider unlocking switch, whereas the a7R IV uses a switchless sliding design which personally I’ve never really liked.

The EVF has a proximity sensor that sits on top with the a7R IV, but it has been moved to the bottom on the a1.

Sony a1

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Sony a7R IV

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The a1 gains a little weight at 737 g (1 lb 10.0 oz) vs the 665g (1lb 7.5 oz) of the a7R IV. This is most likely down to the new processor, shutter mechanism, dual CF Express Type A and UHS-II SD card slots.

When it comes to the menu system the a1 gets a brand new touch friendly menu, whereas the menu in the a7R IV is now looking a little dated and is not touch friendly.

The Sony NP-FZ100 battery can be found in both cameras. In the a1 this will give you around 430 shots when using the viewfinder, or 530 shots with the LCD monitor. The a7R IV beats this by achieving around 530 shots with the viewfinder or 670 shots with the LCD monitor.

Memory Cards

Both cameras have two memory cards slots. But whereas the a7R IV only supports UHS-I / UHS-II SD cards in both slots, the a1 supports the much faster CFexpress type A cards and UHS-I / UHS-II as well (just not at the same time).

Pixel Shift Mode

Pixel shift mode with the Sony a1 gives you the choice of whether to shoot four frames or sixteen. In both cases the files need to be combined using Sony’s Imaging Edge desktop software to create photos with up to 199 million pixels.

The a7R IV also supports Pixel Shift and a choice of four or sixteen frames, but due to the larger sensor the end result is now 240.8 million pixels.

Because the a1 features a much faster electronic shutter, this decreases how long it takes to shoot these images compared to the a7R IV. This should help to reduce the impact of movement between frames, which is the main reason why Pixel Shift images might not always look their best.

Connectivity

Both cameras can be shot tethered via USB or dual-band 2.4 GHz or 5GHz wireless. However, the a1 features MIMO (multi-in, multi-out) technology on the 5GHz band to allow FTP transfers that are 3.5x faster than possible with the a7R IV.

The a1 is the first camera to feature a SuperSpeed USB 10-Gbps (USB 3.2) Type-C connector, whereas the a7R IV has a USB Type-C connector that supports USB 3.2 Gen 1.

The a1 can also be powered over USB-C by using a USB PD power source, but it can’t charge the battery at the same time, you’ll need to turn the camera off to start charging. The a7R IV can only be charged over USB-C, not powered.

The a1 is compatible with the same VG-C4EM battery grip used by the a7R IV, a9 II and a7S III.

Price

The a1 is Sony’s most expensive Alpha camera ever created, with a retail price in the US of $6,498.00, £6,499.00 in the UK or €7,299.00 in Europe for the body only.

In comparison, the a7R IV currently sells in the US for around $3,498.00, £3,199.00 in the UK and €3,999.00 in Europe.

If purchasing the a1 is going to cause relationship issues, then now is probably a great time to purchase a used a7R IV. I already know that many Alpha Shooters are trading in their a7R IV’s to help towards the cost of the a1.

Summary

This was never really a fair comparison since the a1 costs almost double the price of the a7R IV, but I still think it’s an interesting comparison between two high-resolution cameras.

Although the paper specs put the a1 miles ahead of the a7R IV, it will be much more interesting when these two high megapixel cameras are compared head-to-head.

There’s no doubt that the a1 is going to outperform the a7R IV when it comes to AF performance, but what about image quality and ISO performance?

The a7R IV is very good at capturing high resolution images, but it does sacrifice AF performance and frame rate. Whereas the a1 is also able to capture high resolution images but at the same time maintain the blistering fast AF speed from the a9 series. It also adds some pretty incredible video specs that until now have only be found in the a7S III.

Since I run the Sony Alpha Wildlife Shooters Group on Facebook I know that there are many wildlife photographers shooting with both an a9 series camera for capturing fast action, especially birds in flight, but also carrying an a7R III or IV for that additional resolution when tackling slower subjects. With the arrival of the a1, many are now considering consolidating two bodies into one.

So yes, the a1 is super expensive and purchasing it may end in divorce, which will be even more expensive! But you are affectively getting three cameras in one, so when you add up the cost of the a9II, a7R IV, and a7S III, it almost starts to look like good value for money!

Despite the arrival of the a1, the a7R IV is still a fantastic camera. If you don’t need 8k or 4k 120p video, and don’t demand the fastest possible AF performance and frame rates, then the a7R IV should not disappoint you one bit.

I finally decided to pre-order the a1 myself, so I’ll be expanding on this article with some real-life tests just as soon as it lands in my hands.

So which camera would you prefer to have in your gear bag? Let me know in the comments below.