WFCAM 06B news -------------- Unfortunately JAC have yet again "improved" the WFCAM Data Acquisition system leading to a litany of problems. In no particular order: * the first 6 weeks of data taken in NDR mode are in counts/s not counts. Unfortunately the integer Rice compression applied at JAC before writing the FITS tapes to send to CASU renders all the tapes written so far as useless for Y- and Z-band data; * a "zero countdown problem" with the data acquisition has led to large numbers of missing files, partially completed MSBs and restarted MSBs without unique identifiers. This also took several weeks to fix; * there have been long periods, ie. whole nights, when data from various detectors is not present during this period; * the flat field screen is shredding and will be removed. This one at least is not foreseen to be a serious problem from the point-of-view of non-linearity measurements; * in spite of much prompting on our behalf, due to a catalogue of (JAC) errors the first tapes for 06B (26th October -->) did not arrive until a few days before Christmas. There is still a several week backlog of data that we haven't seen, in addition to the NDR problems mentioned earlier. Although none of these are insurmountable, fixing them takes extra effort, but more worryingly the number of these problems seems to increase everytime WFCAM goes back on. WFCAM Products -------------- Measurement of Y and Z zeropoint offsets for Vega A0 type stars is almost complete. No offset will be applied for DR2, however a small offset in Y (around 0.06 but hard to pin down accurately) is likely to be applied in future releases). This will bring these bands more accurately onto the Vega system. The calibration WG are meeting next week to discuss this and other remaining issues. PSF fitting progress update --------------------------- The PSF fitting code has been enhanced to use merged object information from the catalogues. This should improved the efficiency. Tests are being carried out in crowded fields and areas of varying nebulosity. These tests are being carried out in conjunction with Phil Lucas (University of Hertfordshire) who will be using DAOPHOT as a control comparison. UK Review --------- As expected this took up a significant amount of time in the last two quarters. However, it was generally felt to be a useful exercise, helped by the presence of Colin Vincent representing PPARC. CASU welcomed the constructive nature of the report noting in particular the clear statement from the review about the need for the 6 month bridge in VDFS development funding at the current manpower level. One relatively urgent issue highlighted was the need to (re)assess the revised VISTA public survey proposals for their data processing requirements. Consequently an internal meeting was held in the first week of January to discuss these and related questions. Two matters arising from the discussion were (1) All the PI's will need to ensure that their areal coverage estimates allow for the top and bottom 50% coverage strips within a VISTA tile, and (2) The UK pipeline software for combining pawprints into tiles needs to be tested and possibly futher developed with on-sky VIRCAM data as soon as possible. This aspect of the pipeline development is not generally used for processing WFCAM data in part due to the inherent instability of the detectors but also because creating filled WFCAM tiles is not a UKIDSS public survey requirement. CASU noted the recommendation of the panel to release the VDFS pipeline software, manuals and relevant documentation (via) the Plone site, and have begun work on this. VISTA ----- Version 0.4 of the DRL and V1.6 of the DRLD have been sent to ESO for assessment and are currently being tested. The v0.4 release contains 10 out of the 12 intended recipes (cross-talk and persistence measurement are the two outstanding recipes, but both await on-sky data for further progress). The plan is to hold discussions on v0.4 issues during the ESO Calibration workshop in January, so that necessary fixes, enhancements etc. can be agreed on and implemented in time for v0.5 which will be an offical release (target date end of February). This will be a major milestone release in the VDFS 1618 schedule. ESO created a version of the VISTA ETC during the summer and have been comparing outputs with the online version here. Several differences were reported but it quickly became apparent that most of these were due to: the old technical data tables that ESO have; the odd bug fix we have made; and their quaint use of Gaussian rather than Moffat profiles. Consequently PSB has sent them updated versions of the ETC software, tables and documentation. JRL has written a report on the VIRCAM dark frames. The main feature is that there are large numbers (a few %) of hot pixels and related artefacts, the majority of which are well-behaved. Flatfielding seems to work as expected, with the (not unexpected) proviso that the flatfield must be taken using the same observing parameters as the target frames. It was noted that on detector 14 a whole channel seems to have intermittent bar-code-like noise.