Sony has unveiled two full-frame E-mount compact system cameras (CSCs) which it claims have a faster AF than the Canon EOS 5D Mark III, under certain conditions. Despite this boast, the firm insists it has no plans to pull out of the A-mount camera market.

Amateur Photographer’s First Look of Alpha 7 and Alpha 7R

The Alpha 7 and low-pass filter-less Alpha 7R (due from mid-late November) are part of a Sony plan to make full-frame cameras more accessible to enthusiasts – bringing down prices in this sector.

Aimed at advanced amateurs and professionals, the Alpha 7R contains a 36.4-million-pixel imaging sensor and will cost £1,600, while the 24.3MP Alpha 7 will come with a £1,300 pricetag.

Identical in size, the magnesium-bodied ‘palm-sized’ models are targeted at the DSLR market and not the mirrorless camera arena.

Sony officials told Amateur Photographer (AP) that the company is keen to change the ‘general impression’ that CSCs have ‘slower AF’.

Sony claims that the A7R has an AF speed around 35% faster than the NEX-7 and which, under certain conditions, surpasses the Alpha 99 full-frame DSLR.

New ‘Fast Intelligent AF’ is designed to be fully customisable, using nine buttons and 46 assignable functions.

The A7R uses a 25-point contrast detect AF system (the A7’s hybrid AF system contains 117 phase- detection AF points and 25 contrast detect points).

The A7R is billed as the smallest and lightest system camera with a full-frame sensor (407g body only).

ISO sensitivity of 100-25,600 is designed to expand to ISO 50-51,200, and Smart Remote Control should allow exposure adjustment and shutter release via a smartphone.

‘We will not quit A-mount’

Asked what message Sony has for A-mount users with large lenses that do not suit the shorter back focus of E-mount cameras, Sony UK’s Alpha product manager Takahiro Hirata, said: ‘We will not quit A-mount product lines. We will have both product lines.’

The new CMOS sensor on board the A7R features a ‘new gapless on-chip lens design’, claimed to boost the sensor’s light-capturing efficiency. Sony engineers stress the importance of this, given that the flange back distance on E-mount models is 40% shorter than on A-mount cameras.

The flange back distance is the distance from the rear of the lens to the imaging sensor plane.

The A7R’s Bionz X image processing engine is built to be three times faster than previous versions. Combined with Detail Reproduction Technology this will cut noise, even at high ISOs, claims Sony.

Features on the ‘dust and moisture-resistant’ models include a 2.4-million-dot electronic viewfinder, 3in (921,600-dot) LCD screen, Wi-Fi connectivity (including Near Field Communication) and 1,200-zone metering.

The A7 and A7R will be compatible with a new battery grip (VG-C1EM) and new A-mount adapters, due out at the end of November, one of which (the LA-EA4) contains an AF motor.

In an interview with AP, Sony Japan software engineer Youichi Hasegawa said the Bionz X processor contains a new AF algorithm to help improve contrast AF, and enables better communication with new Sony lenses (see below).

In a slide presentation, Sony claimed that faster assessment of ‘subject distance, and adaptive selection of the lens drive speed, based on the size of the focus gap’, have boosted focusing response and cut ‘lens-drive overuns’.

‘The result is smooth, high-quality, autofocus on subjects with [the] swiftness of SLRs.’

Full-frame E-mount lenses

Sony is poised to debut five new ‘full-frame’ E-mount lenses over the next few months: a 35mm f/2.8 ZA (due end of November); a 24-70mm f/4 ZA OSS (January); 55mm f/1.8 ZA (January) and 28-70mm f/3.5-5.6 OSS (spring 2014).

At the end of this month we can expect a revamped A-mount 70-200mm zoom, the f/2.8 G SSM II, and by next spring an E-mount G lens in the shape of the 70-200mm f/4 G OSS.

A Zeiss-branded f/4 ‘ultra-wideangle zoom’ and ‘large-aperture prime’ are also on the horizon, according to a Sony roadmap seen by AP.

Future full-frame E-mount optics are also set to include a new macro G lens.

The cameras took two years to develop and will be made in Thailand.