Narrow band filters

This week of commissioning started with Charles and Brent spending an entire day mounting reshuffling the large ODI filters and installing five new filters into the ODI filter mechanism. With the addition of four narrow band filters, and one SDSS u' band filter, all nine slots in ODI are now occupied. The new filters are 5 3/4 inch sized filters loaned from the KPNO and CTIO Mosaic cameras, so we do not get the full field of view. The canonical choice for the narrow band filters included an H alpha and O[III] filter – expect some nice images to show up over the new few weeks.

Monday night Ralf Kotulla (UW Milwaukee) took a first demonstration picture of M33 in H alpha, which nicely complements last run's U band image taken of the same galaxy. In the picture below we show only the unvignetted 2x2 detectors array. The total field coverage is slightly larger, though.  The exposure time of the single image was 450 seconds, but we observed the frame as part of a larger dither pattern. I cannot wait to get a full color image of M33.

Daniel

M 33 – 450 sec in H alpha