Also here is interesting experiment using b-spline resize on original dng to 4464:

Looks like using b-spline gets rid of more staircases but perceived sharpness isnt as good.It is interesting option to have IMO.You could then sharpen in post with less aliasing.
@2blackbar: Interesting, the example looks much better with b-spline, how exactly did you do b-spline on the DNG, what software what picture formats etc?
@Danne: Looking at the examples, are you sure horizontal pixelbinning is done in this 1x3 mode ?
On the 6d I use this part for 1x3 mode for pixelbinning:
case CROP_PRESET_1x3:
case CROP_PRESET_1x3_24FPS:
adtg_new[11] = (struct adtg_new) {6, 0x8000, 6}; // 6=pixelbinning (8183&8184 needed) 5 is not pixelbinning.
adtg_new[12] = (struct adtg_new) {6, 0x800C, 0}; // lineskipping
adtg_new[13] = (struct adtg_new) {6, 0x8183, 0x35}; //sets horizontal pixelbinning, needed if pixelbinning is wanted in 5x zoom mode
adtg_new[14] = (struct adtg_new) {6, 0x8184, 0x3b};
Because I use 1x3 mode in 5x zoom mode, I need to set 8000 register to value 6 and I have to set values for 8183 and 8184 registers (default values Canon uses in normal non zoom mode)
The difference between horizontal binning or not is very big, both pictures are from 1x3 mode on 6d, the left does horizontal pixelbinning, the right one not.
