P2PP: WFI Information
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This page contains information specific to the creation of Wide-Field Imager (WFI) Observations Blocks (OBs) for Service Mode programmes. For general information on the creation of OBs and the contents of Phase 2 packages for Service Mode observations with WFI, please read the VLT and ESO-MPI 2.2m Service Mode Guidelines. Note especially that observing runs that cannot adhere to procedures and policies presented in that document and the instrument-specific information described in this Web page must request a Phase 2 Waiver Request at least one week before the Phase 2 deadline.

News

• Starting in Period 79, the validity checks for WFI OBs are done by P2PP. That is, the WFI Phase 2 procedures have now been brought in line with the VLT operational model.
  
  
• Starting in Period 74, standard stars are observed with only one integration time per filter. See the WFI Calibration Plan webpage for details.

Table of Contents

• Documentation
• Unsupported Features
• Execution Time and Time Charged to Programme
• WFI Specific Finding Chart Requirements
• Final Pre-Submission Checklist

Documentation

• WFI User's Manual

• WFI Template Reference Guide (as part of WFI User's Manual)

• P2PP User Manual

• Please also be sure to review the revised calibration plan before completing your Phase 2 submission. Standard calibrations are done in the U/50, B/123, V/89, Rc/162 and I/203 filters ONLY, see further details on the WFI Calibration Plan web page.

Useful tools for Phase 2 (including exposure time calculator, object visibility, catalogues...) are available.

Unsupported Features

• CCD binning different from 1x1;
• Filters other than those provided by ESO (the WFI filter list is available);

Execution Time and Time Charged to Programme

Time will be charged to your programme for:

• all scientific fields;
• non-standard night-time calibrations (e.g. spectrophotometric standard stars in bands other than the UBVRI filters supported by the calibration plan);

Time will not be charged for:

• any dusk/dawn flat-fields, whether for standard or non-standard filters, (although ESO reserves the right to alter the number of dusk/dawn flat-fields specified for non-standard filters, to optimise the use of dusk/dawn hours);
• any daytime calibrations, whether for standard or non-standard filters, (although there is a cap on the time available for non-standard daytime calibrations equal to 10% of your OPC allocation).

Finding Charts Requirements

The large WFI field-of-view (34 arcmin x 34 arcmin) leads to special finding chart requirements besides those described in the general Finding Charts creation instructions given in the Service Mode guidelines webpage:

• Create at least one finding chart for each new pointing. If the coordinates of one OB differ from those of another by more than 1 arcmin (in any direction), then a new chart is required. Charts should be exactly 34 arcmin x 34 arcmin and be centered precisely on the same RA, Dec and equinox as used by the OB.
• Line-drawn charts are prefered over image-based charts (e.g. like DSS) because of the large fields involved.
• Field objects should not be labeled with numbers or additional symbols.

To create good charts, use the following sites, listed in our descending order of preference:

1. APM Catalogues: these are based on both the POSS I and USKT surveys. Note that scanning of the UKST survey is not yet complete. There is also an APM interface at IoA, Cambridge. You can download an example APM chart for perusal.

2. Revised APS University of Minnesota Catalog. This is based on POSS I and so covers the northern and equatorial skies down to declination -30. Be sure to check availability of your fields first. When creating the charts, use colons (:) to separate RA and Dec components and select a Faint magnitude limit = 18.0. Also use the options sky map with RA,Dec, coordinate grid = no, labels = no and Open galaxies + filled stars for symbols. Be sure to produce a Postscript plot with Portrait Orientation on A4-sized paper. You can download an example APS chart to see the finished product.

3. CADC Digitized Sky Survey Interface. Only use this as a last resort, if you really cannot use 1 or 2 above. Digitised charts of WFI-field size are files 10 to 20 times the size of equivalent line-drawn chart files. You can download an example DSS chart for inspection.

If you use one of these sites, your charts will automatically satisfy the following requirements:

• RA, Dec and equinox are clearly shown,
• north is up and east is left,
• the chart has dark print on a light background,
• the scale is shown (except in the case of APM finding charts, where it will be assumed that the plotted area is 34' in size)

In addition, you must add the information listed in the general description of requirements for finding charts

Finally, if there is a particular object of interest in the field, that needs to be positioned on a particular pixel, (or kept away from bad columns or inter-chip gaps), then please indicate it on the chart. If it is not visible on the wide-area charts, then make a second chart that zooms in on the object, showing on the wide-area chart the location of the small-area chart. Remember to indicate the scale on the second chart and include all of the features listed above. Note that the smaller-area chart is not a substitute for the wide-area chart.

An example of a suitable finding chart is available.

Final Pre-Submission Checklist

Please answer one of: Y = Yes, N = No, NA = Not Applicable

Do each of your OBs take less than 1 hour to run?               [Y/N/NA]

Do each of your OBs have all Observing Constraints filled-in?   [Y/N/NA]

Have you included OBs for any calibrations that you need but 
which are not a part of our set of Standard Calibrations?       [Y/N/NA]

Do each of your OBs have names of 12 characters or less, and 
names without spaces or parentheses?                            [Y/N/NA]

Do all of your OBs have unique names?                           [Y/N/NA]

Are your finding charts 34 arcmin x 34 arcmin?                  [Y/N/NA]

Are your finding charts labelled with RA, Dec, equinox, a scale, 
the PI name, the programme ID, the OB name(s) and target name?  [Y/N/NA]

Are your finding charts dark print on a light background?       [Y/N/NA]

Have you supplied additional small-area finding charts for any 
precise offsets or move-to-pixel/gap requirements?              [Y/N/NA]

Have you checked your OBs against the checklist in Section 6.2 
of the WFI Templates Manual?                        [Y/N/NA]