Test the Sony Alpha 7
If there's one thing you can say about Sony's digital camera business, it's that they've experimented with a lot of different concepts. SLRs with automatic focusing systems...
13/09/2021
If there's one thing you can say about Sony's digital camera business, it's that they've experimented
numerous
different concepts. DSLRs with
dual autofocus systems
and
'Translucent' mirror technology
to its NEX mirrorless line, Sony has virtually every avenue of digital imaging. Its latest products - the Alpha 7 and Alpha 7R - might be the most exciting products to come out of Sony's labs in quite some time. The company has managed to create full-frame cameras that are roughly the same size as the Olympus OM-D E-M1
. In other words, the Alpha 7s are
a lot
smaller than their full-frame interchangeable-lens counterparts (like the Nikon D610 and Canon EOS 6D), an achievement made possible primarily because they're not SLRs.
Additionally, Sony is also unifying the Alpha and NEX brands, so all future interchangeable lens cameras will now fall under the Alpha umbrella. Being mirrorless, the a7 would probably have been prefixed with the letters NEX.
The a7 and a7R are identical in terms of physical design, the main differences being the sensor and autofocus system. The a7 features a 24-megapixel full-frame CMOS, while the a7R has a 36-megapixel CMOS sensor with no optical low-pass filter. The a7 uses a hybrid AF system (with on-chip phase detection) similar to that found on the NEX-6, while the a7R has traditional contrast detection. The a7 is also capable of electronic first-curtain mode, which allows for a quieter shutter and reduces the potential for 'shutter shock' vibration; this is absent from the A7R. Both cameras use Sony's latest Bionz X processor and also feature XGA electronic viewfinders, tilting LCDs, Wi-Fi and weatherproof housings that resemble those of the Olympus E-M1.
As you'd expect, Sony had to come up with new lenses to take advantage of full-frame sensors, and they'll be known as the 'FE-series'. Five lenses have been announced to start (listed below), with ten more promised by 2015. Existing E-mount lenses will work, although the image will (necessarily) be cropped. If you have A-mount lenses, these will also work, provided you choose one of Sony's full-frame compatible adapters (LA-EA3 or LA-EA4).
Sony a7 main features
24.3MP full-frame CMOS sensor with OLPF
E mount with support for FE, E and A mount lenses (with adapter)
Bionz X Image Processor
Hybrid AF system with 25 contrast detection points and 117 phase detection points
Sealed and composite alloy body
Multi-interface claw< /p>
3-inch tilting LCD with 1.23 million dots (640x480, RGBW)
XGA electronic viewfinder (1024x768)
Diffraction correction technology
Full HD video recording at 1080/60p and 24p; uncompressed HDMI output
Wi-Fi with NFC capability and downloadable apps
The a7 uses a 24.3 megapixel CMOS sensor
with
has low-pass filter and on-chip phase detection. This "Hybrid AF" is supposed to result in faster autofocus, supporting the camera's ability to shoot at 5 fps with continuous autofocus. The more expensive a7R, on the other hand, has a 36-megapixel sensor without an optical low-pass filter and a more conventional contrast-detection AF system.
The a7 and a7R can record video at 1080/60p and 24p, with manual exposure control, headphone and mic ports, audio meter, zebra pattern, XLR support (via adapter) and live, uncompressed HDMI output.
Bionz X processor
The company's latest processor, dubbed Bionz X for reasons that seem logical to someone, is considerably more powerful than the previous generation, allowing for what the company says is more sophisticated processing.Sony is a little vague on the details, but touts the new processor as offering "detail reproduction technology" which appears to be a more subtle and sophisticated sharpening system. The company promises less apparent emphasis on edges, giving a more compelling depiction of fine detail.
Another function promised by the Bionz X processor is 'Diffraction Reduction', in which the camera's processing attempts to correct the softness caused by diffraction when you reduce the aperture of a lens. This processing is presumably aperture dependent and looks like part of Fujifilm's Lens Modulation Optimization system (introduced on the X100S), suggesting it's something we should expect see it becoming more common among brands in the coming months.
Finally, Sony says the Bionz X chip offers a more advanced version of its contextual "area-specific noise reduction", which attempts to identify whether each area of an image represents soft tone, textured detail, or edges. of the subject and applies different amounts of noise reduction accordingly. Later in the review, we'll show you how well this system works, as well as the problems it can create.
Goals
Although the a7 has an E-mount, you'll need to use Sony's new FE-series lenses to take advantage of its full-frame sensor. Existing E-mount lenses will still physically fit, but since they're only designed for use with APS-C sensors, their image circles won't properly cover the entire frame (much like using DT lenses from Sony on full frame Alpha mount cameras). While five FE lenses were announced at launch, not all of them were available at 'press time', and the 28-70mm F3.5-5.6 OSS will only be sold as a kit for the a7. All lenses are weather sealed, but while the zoom lenses include optical stabilization, the prime lenses do not.
Here are the five FE lenses that have been officially announced:
Model< /p>
MSRP
Availablity
24-70mm F4 Carl Zeiss OSS
$1199/£1049
February2014< /p>
28-70mm F3.5-5.6 Sony OSS
kit only
Now
70-200mm F4 Sony G OSS
To be determined
To be determined
35mm F2.8 Carl Zeiss
$799/£699
Now
< p>55mm F1.8 Carl Zeiss$999/£849
Now
Sony plans to have a total of fifteen FE lenses by 2015, including macro and ultra-wide models.
The first five Sony FE lenses include two standard zooms, two primes and a telephoto zoom
We're slightly surprised by Sony's strategy here: it seems little odd to do two different standard zooms to start with, rather than adding a wide-angle zoom. And while it's nice to see some bounties, both seem a bit slow considering their prices. The 55mm F1.8 is also a bit long for a “normal” lens. We would have liked to see a fast 'portrait' lens in the 85-135mm range early on, but hopefully Sony will offer one soon.
Both cameras are fully capable of using existing E-mount and A-mount lenses, and you have the choice whether or not to crop the image. If you choose to crop, the resolution will drop to 10 megapixels on the a7 and the equivalent focal length will increase by 1.5X. Sony also gives you the option of not cropping and using the full sensor, although this may lead to heavy vignetting.
Image 1 24mm Full Frame Lens - APS-C Crop Off
< p>APS-C Image 2 24mm Lens - APS-C Crop OffImage 3 24mm APS-C Lens - APS-C Crop On
The camera offers three options for its APS-C crop mode - Off, Auto and On. When off, you will see frame 1 with a full frame lens and frame 2 if you are using an APS-C lens. With the switch to Auto mode, you'll get frame 1 or frame 3, depending on whether you're using a full-frame or APS-C lens. And finally, when enabled, you will see frame 3 no matter what type of lens you put on the camera.
The a7R with LA-E4 A-mount adapter and 50mm F1.4 Zeiss lens< /p>
Sony's A-mount lenses require the use of an A-to-E-mount adapter. Somewhat confusingly, Sony now offers no less than four such adapters, which differ in their autofocus capabilities and coverage. format. The LA-E1 and LA-EA3 offer contrast-detection autofocus for lenses with built-in focus motors (i.e. SAM and SSM), but only manual focus with other lenses, while the LA-EA2 and the new LA-EA4 use Mirror Technology to offer autofocus with all lenses. The LA-EA1 and LA-EA2, however, were designed for APS-C NEX cameras and vignette heavily when used on the a7(R); the LA-EA3 and LA-EA4 are required to provide full sensor coverage with full frame lenses.
Adapter
Full autofocus?
Ready for full frame?
LA-EA1
Nope
Nope
LA-EA2
Yes
No
LA-EA3
Nope
Yes
LA-EA4
Yes
Yes
It should be noted that the a7 and a7R are capable of accepting a huge range of other lenses via readily available third party adapters, including older manual focus lenses from long dead systems such as Minolta MD , Olympus OM and Canon FD, as well as those of current systems such as Nikon F, Pentax K and Leica M. Also, in principle, these lenses should offer the angle of view for which they were originally designed - so a 24 mm will again be a real wide-angle, for example. So if you have a treasured collection of old manual focus primers in a closet, the a7 may be just the camera to bring them back to life. More on that later in the review.
Kit options and prices
The 24-megapixel Alpha 7 retails for $1699/£1299 only and $1999/£1549 with the 28-70 F3 .5-5.6 OSS lens. For those curious, the 36-megapixel a7R is priced at $2299 / £1699 only.
The most notable accessory for both cameras is an optional battery grip (VG-C1EM) - a first for an E-mount camera. This grip adds controls for vertical shooting and packs an extra battery, and will set you back around $300/£259.
The a7 does NOT come with an external battery charger, instead relying on internal charging via USB. USB charging is quite slow (and it's harder to have a spare battery handy), so it's probably a good idea to grab the BC-VW1 or BC-TRW external chargers.
Other accessories include camera cases, an external flash adapter, wired and wireless remotes, and screen protectors.