For our measurements, we use the sequence mode to upload binary random masks straight into the device flash memory (stored pattern sequence mode). We use the NxM masks, which are resized to follow the native resolutions of the DMD (684 x 608). We found out that a mask pixel has to be represented by whole number of DMD pixels in both horizontal and vertical directions. Once this condition is not met, the moiré effect occurs during the Single Pixel Camera reconstruction.
Our issue is that once we try to use the resolution of 152 pixels in horizontal direction (the ratio of DMD to mask pixels is exactly 4), the condition above is met, but the moiré effect occurs once again (one light and one dark fringe alternating). Another interesting phenomenon is that this effect occurs only in the horizontal direction, the vertical mask resolution can be arbitrary. We haven't come up with any reasonable explanation, apart from one where the system somehow interpolates the image before the display and the display is therefore not, lets say, straightforward.