Mixed up market – specced up compacts, dumbed down DSLRs

Canon has pulled off another change in the direction of DSLR development with the EOS 650D, but in the process seem to have accepted a blurring of the boundaries between consumer cameras and enthusiast gear. Sony has finally bowed to pressure and put raw image processing back into a compact, using a larger than normal sensor, doing the same in reverse.

To explain, neither of these cameras belong within Photoclubalpha – we don’t usually report on Sony Cyber-shot compacts, equally rarely on Canon’s latest competitor to the A57. But these two cameras are waymarkers. They show us where two strands of development are heading, and how they are converging.

Canon EOS 650D

650D with new 18-135mm STM lens, required stepper-motor technology for off-sensor video auto focus

The new points about the 650D (also known as the EOS Rebel T4i for that least rebellious of areas, the USA) are simple enough. It’s yet another 18 megapixel APS-C model in the series 500/550/600 rather than the more professional 50/60/7 body form. Maximum frame rate is 5fps. It has full 1080p HD, but only at 30fps maximum (720/60p) with a 5.5MB/sec data rate. Unlike previous models, this one can focus during video shooting, and may well do it better than a NEX.

It has a conventional 9-cross point phase detect AF module much improved over earlier versions, included a central double-cross f/2.8 sensitive point. When shooting video, hybrid AF combines normal wide area contrast-detection with a similar centrally located phase-detect pixel arrangement that offers much faster locking on before the CD takes over to fine tune and track moving subjects or faces.

No visible signs on the CMOS – but that sensor had a phase-detect central zone

So there are two AF systems, one of which remains live for video. To work properly it needs a new type of lens motor, called STM. This stepping motor appears to be not unlike the NEX system lenses, offering the necessary control for AF during video with silent action. Just two lenses initially have it, a pancake EF 40mm f/2.8 STM and a general purpose stabilised EF-S 18-135mm f/3.5-5.6 IS STM. If you know your Canon system terminology, you’ll spot that the 40mm is compatible with full frame DSLRs it’s not just an odd 64mm equivalent for the APS-C models.

With other lenses, the implication from Canon is that AF during movie shooting will not work. That includes the cheapest kit option, the 18-55mm. No matter what type of USM or micromotor AF drive. If you want video with AF, you need the new STM lenses.

The Canon phase-detect on sensor is purely a central patch, not an overall function like Nikon’s 1 system 71-point PD. But, like consumer cameras, Canon adds touch screen functions to the 650D. This is a response to consumer demand. You can still operate the camera with the rear screen completely reversed. I have to admit that the first thing I did with the NEX-5n was to disable the touch screen function, and never use it.

For a Canon, the 650D has a surprisingly limited battery range, as low as 180 shots per charge if live view, flash and image review functions are used in their worst-case scenario.

The Sony Cyber-shot RX100

A neat metal bodied almost Samsung-like compact, the RX100 has an 8.8 x 13.2mm sensor, the 1/1 or one-inch ‘1’ format already used by Nikon. It offers a stabilised Carl Zeiss 28-100mm equivalent lens which is very fast (f/1.8 at the wide end, f/4.9 tele) and may be of enthusiast-pro quality, and a 3″ rear screen where daylight viewing brightness is enhanced using white pixels as well as RGB.

The RX100 offers full HD movies at 28M bitrate – 1080/60p equal to NEX and Alpha. It also seems to get reasonable life from a small battery, 330 shots or 165 minutes of movie, and to have a decent 2.5fps conventional fps plus the popular Sony 10fps speed piority mode.

For most of us, the really big news is that for the first time since classic bridge camera models like the F-828 Sony has decided to provide raw image capture in a pocketable compact. No doubt the success of the Fuji X10, Canon G1X and others has been observed. It is fair to say that Sony could have put raw capture into far more compacts – they all have it hidden away away, an ability carefully locked out by firmware.

To date, we have felt that Sony wanted to protect the NEX and Alpha markets at any cost by omitting raw even from the best Cyber-shot models. The RX100 changes this perception. It leaves the expensive semi-pro hybrid video and still camera, the NEX VG-10, looking a bit sad with its JPEG-only still capture. After all, if compact owners do indeed want raw, surely VG-10 owners would be expected to want no less?

And that sensor is 20 megapixels. It’s twice the pixel count of the Nikon 1. There was a time something like happened in the past. Nikon made a camera called the D1 (then D1X) which had a 5-megapixel sensor, and then a sort of firmware and processing fix to make it halfway like a 10 megapixel sensor. It was revealed that the ‘rectangular pixels’ of the D1 were actually two pixels in a strip. When a different RGB topping and readout was applied to the same exact silicon, it became the Sony 10 megapixel sensor we saw in the Alpha 100 (and the Nikon D200). Nothing like that could possibly have happened with a Sony 20 megapixel sensor to make a Nikon 10 megapixel sensor, even though they both share the same unusual 8.8 x 13.2mm size.

And even though Nikon uses a whole stack of pixels on that sensor to perform phase-detection AF without any apparent loss of those pixels to the image – spread out over 71 points across the entire frame too. There’s no way, is there, they could ever have based that 10 megapixel PD-AF capable sensor on a Sony 20 megapixel original.

– David Kilpatrick

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