Mid- to far-infrared views of the central part of Ou4. a) WISE 12 μm (W3-filter) image. b) WISE 22 μm (W4-filter) image. c) IRIS 12 μm image. d) IRIS 25 sμm image. e) IRIS 60 μm image. f) IRIS 100 μm image. g) INT [O iii] image for comparison purpose. The contour map is the 22 μm emission from 89.375 to 92.5 digital numbers (DN) with linear step of 0.446 DN (i.e., from 2.471 to 2.557 mJy/arcsec² with linear step of 0.012 mJy/arcsec²). The FWHM resolution is plot in the bottom-right corner of each panel. The two large circles are the regions used for the aperture photometry (see text and Fig. 14).