Phase One IQ250 medium-format camera back is faster, better in low light, and still very expensive


posted Friday, January 24, 2014 at 4:55 PM EST


A few days ago, we told you about Hasselblad's plans for the upcoming H5D-50c DSLR, the first medium-format camera to feature a CMOS sensor instead of the more traditional CCD chip. Well, if you're willing to broaden the definition a little and include medium format camera backs, they've just been pipped to the post by Phase One, who're now selling the IQ250 medium-format digital camera back -- and it too is CMOS-based.

So what does the switch to CMOS net you? Well, for one thing, the Phase One IQ250 has a much wider ISO sensitivity range, covering everything from ISO 100 to 6400 equivalents. That compares very favorably indeed to the ISO 800 limit of the existing, CCD-based IQ260 and IQ280 backs. In fact, even reducing resolution by three-quarters would only allow these older models to reach a limit of ISO 3200, while the IQ250 peaks at ISO 6400 with full resolution.

An introduction to the Phase One IQ250 with principal firmware architect Søren Ilsøe.

Dynamic range of the new chip is also said to be better, at 14 f-stops, versus the 13 f-stop range of the earlier CCD-based models. And performance, too, is improved. The IQ250 can shoot 1.2 frames per second at full resolution, up from 1.0 frames per second in the 60-megapixel IQ260, and 0.7 frames per second in the 80-megapixel IQ280. And the Phase One IQ250 also adds live view functionality not found on its CCD-based siblings.

Perhaps in part accounting for the slightly faster capture rate -- although the resolution is also lower -- the IQ250 has double as much buffer memory as its older siblings, with 2GB available in total. Shutter speeds range from 1/10,000 second to 60 minutes, just as in the IQ260.

So is there a drawaback to the use of CMOS? Well, the chip chosen -- rumored to be sourced from Sony, although we haven't been able to confirm that independently -- is quite a bit smaller than the CCD sensors in the IQ250 and IQ280, reducing the prospects for wide-angle photography. Sensor size is 44 x 33mm, yielding a 1.3x focal length crop compared to the earlier models.

The Phase One IQ250 camera back attached to a 645DF camera body with Schneider-Kreuznach lens.

The Phase One IQ250 is available for use with a variety of cameras, including the Phase One 645DF, Mamiya 645DF, Hasselblad's H1, H2, 555ELD, 553ELX, 503CW, and 501CM, and the Contax 645AF. Adaptors allow use with even more models from Alpa, Arca Swiss, Cambo, Linhof, Mamiya, Toyo, Sinar, Plaubel and Horseman.

Pricing for the Phase One IQ250 with Capture One software is set at around US$35,000. In Europe, the pricetag is around €25,000, making the camera back slightly cheaper there at current exchange rates (and ignoring taxes and duties.)

More details can be found on the Phase One website.