The present invention prevents ink leaked from an atmospheric pressure introducing port of an ink cartridge from adhering to an outer surface of the ink cartridge. The columns are all generally similar and the beams are all generally similar, such that each column can be attached with up to four beams. Measurements y, comprising a vector with n entries, where n is less than m, are made. Detachable shoulder straps may be attached to the underside of the seat section, so that the entire chair and blind combination may be carried on a hunter’s back into the field. The plurality of small pixels read out the signal charges.