Anyone Got the 7D?

[Daniel Browning]

If I shoot 10MP Medium RAW images with my EOS 7D, is the camera only recording what hits (roughly) every other pixel,or is the camera taking an 18MP image and then using its computing power to downsize that image to a 10MP file?

The latter. On previous cameras they did the full, normal demosaic process (using all pixels), then downsampled to the lower resolution (still using all pixels). I would guess they are doing the same on the 7D.

I am curious if I would see improved OR worsened noise performance at say (10MP RAW and ISO3200) than at (18MP RAW and ISO3200 downsized to 10MP in photoshop post-processing). Or if the noise would be the same, it would save me a lot of time (and hard drive space in post-processing)

With downsampling, the noise can never be better, but with the ideal downsampling filter, the noise will be the same. Many slightly imperfect filters, like all the ones Canon had before, increase the noise slightly. It also causes an increase in aliasing.


However, downsampling isn't the only option. It would be possible for Canon to use on-sensor binning (connecting multiple pixels together electronically), and that would theoretically reduce read noise (shadow noise). However, it may require additional transistors on the pixel, and they would have to solve some other difficult problems such as aliasing (much worse than aliasing from downsampling).


Most people find sRAW to be perfectly acceptable, I think you will too.