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Just as I got a new digital camera with a monster resolution of 45.7Mpixels (that is over 100 times the resolution of my very first digital camera, a Sony Mavica, back in 1997; the very first digital camera goes back to 1975 when Kodak took the first digital shot with a sensor having 10,000 pixels and it took them 23 minutes to transfer the image to a mag tape…) I see the announcement of the new Hasselblad camera that offers 400Mpixels resolution! It is unfair.
More than my displeasure of having been made obsolete on the very day that I got my new camera the reason for posting the news is tied to the amazing engineering feat that is allowing Hasselblad to deliver such a resolution.
The camera has a 100Mpixel sensor, quite impressive but considering the the camera is a medium format it is not surprising (my camera sensor is 24×36 whilst the Hasselblad has a 53.4×40, which means it is 2.4 times larger hence the resolution per square mm is about the same). How did they boost that resolution four times up to reach 400Mpixels?
For once, it is not a software trick (at least, not completely). What Hasselblad engineers did was to create a moving sensors that can shift on the x and y axes to allow taking the same photo from slightly different position (we are talking µm shifts here). The camera takes 6 photos in succession each one with the sensors slightly shifted and then recombine them into a single 400Mpixel photo (23,200×17,400 pixels; mine: 8256X5504).
Now, you may ask: why not have a larger sensor if you want higher resolution? The problem is that a larger sensor surface would require larger, heavier and much more costlier lenses (the cost to manufacture a larger sensor is larger than manufacturing the same surface through smaller sensors but not so much larger; the real show stopper is the manufacturing of larger lenses whose cost grows exponentially with the size).
A similar question would be: why not cram more pixels into the same size sensor as it is done in the small smart phones sensors (a smartphone pixel area is almost 20 times smaller than a DSRL digital sensor)? The reason is that the smaller the sensor photosite (the pixel) the worse the image quality. That is why the idea of shifting the sensor is so ingenious!
Of course this works only if your subject is standing still so that the 6 photos can be effectively recombined. This camera has been designed for reproduction of art masterpieces where the resolution and colour fidelity is of outmost importance. The masterpiece is standing still and so there is no problem.
An amazing technology but just wait before rushing to get yours: be prepared to pay 47,995$ (tax excluded, of course). All considered, I can leave with my new camera.
