BAA Photometry Database Guide to Investigating Observation Loading Warning
and Error Messages
Contents
How
to Resolve Some Common Warnings and Errors
Overview
Whenever you upload, manually enter, or edit observations, the data goes through a series of checks to ensure the values are valid, and where possible that they are consistent with expectations.
The checks are split into two types:
· Errors
o These will prevent the data from being loaded or changed.
· Warnings
o The data will still be loaded or changed, but the warnings should be reviewed to make sure there are no unexpected problems with the observation.
o IMPORTANT NOTE – Observations that generate only warning messages will reach the holding area where they must be committed or deleted. Otherwise you will get a duplicate observation error message if you try to reload the observations. You can view observations in the holding area by clicking on “Review and Commit Uploaded Observations” from the homepage.
The checks happen in two main phases:
· Initial checks on individual data items.
o Data type checks like if a number is expected for a field then the value is a number.
o At this point any warning or error messages are reported as row numbers, since the data has not yet been assembled into an observation record.
· Checks once the data has been assembled into an observation record.
o For example does the UT date time match the Julian Date.
o Here warning and error messages are reported against observation numbers, since the row number from original file no longer has a meaning at this point in the processing of your data.
How to Resolve Some Common Warnings and Errors
Below is a summary of some of the more frequent warning and error messages, and how to resolve them.
Sequence (Chart) Warning
One of the most common warnings is that the sequence (chart) is not recognised. A typical message would be:
Sequence '26.02' not found in the database.
If you do not expect the sequence to be in the BAA database then this message can be ignored. For example modern AAVSO sequences are not recorded and so you would expect to see this warning and it may be safely ignored.
If you expect the sequence to be recognised by the database, e.g. the sequence is from a BAA VSS chart, then this probably means you have used a sequence/chart name that is not recognised.
You can view a list of valid sequence names on the website by following these steps:
1. Navigate to the following web page
· Home → Standing Data and Summaries → Sequence Versions and Alias Names
2. Type in the “Object Id” or “Sequence Id” for the star of interest.
· Note stars can be known by many alias but the “Object Id” you need to type in is the primary name by which the star is known to the database.
· To check the “Object Id” navigate to the following web page:
Home → Standing Data and Summaries → Object Alias Names
· Type in the star name in the “Object Alias” box.
· Click “Apply Filter”.
· If the star is in the database then the “Object Id” will be given in the column of that name.
3. Click “Apply Filter”.
4. The “Sequence Alias” column will give you the list of the sequence names for the star.
· The sequence versions are the unique sequences. There may be 1 or many sequence versions for any given object as magnitudes get updated and stars added or dropped from the sequence.
It may also help to see the sequence, so you can tell whether you have the correct sequence alias by viewing the magnitudes
1. Navigate to following web page:
· Home → Standing Data and Summaries → Sequence Data
2. Select the star from the drop down list.
· Typing the first few letters of the “Object Id” will get you close to the star in the list.
3. Press “Fetch Sequence”.
4. All the difference sequences will be displayed in columns.
· At the top of each column is the primary alias (name) by which the sequence is known. This is the best name to use for the sequence, but there are usually other alias names setup. These can be reviewed by the above procedure.
If none of the sequences match your chart but you expect the chart to be present, for example if it is a BAAVSS chart, then please contact one of the BAAVSS officers. Contact details can be found on the BAAVSS website and are on the back cover of the circular.
Mag Check Warnings and Errors
The observation loading software will attempt to verify the magnitude you supply from either the visual estimate, or from instrumental magnitudes if you provide them in a CCD file.
An error message will most frequently be generated because the magnitude you supplied does not match the magnitude that was calculated by the software. There can be a number causes and below are some suggested checks you can carry out.
· Visual
o Check for typos in the light estimate and magnitude that you entered.
o Check your calculation and rounding.
§ Visual estimates should be rounded to 1 decimal place.
§ Round to the nearest 0.1 magnitudes, rounding “half up”, e.g.
1.05 rounds to 1.1
1.04 rounds to 1.0
o Check your comparison star magnitudes.
§ The magnitudes within a sequence can be viewed from the web page:
Home → Standing Data and Summaries → Sequence Data
· CCD
o Check your file for any obvious problems, like zero magnitudes or magnitude errors, or missing values.
o Check your comparison star magnitudes.
§ The magnitudes within a sequence can be viewed from the web page:
Home → Standing Data and Summaries → Sequence Data
Warnings will typically be for the following reasons.
· The magnitude could not be calculated because the sequence could not be found.
o Try looking up the sequence from the following web page:
Home → Standing Data and Summaries → Sequence Versions and Alias Names
· The magnitude could not be calculated because one or more of the comparisons was not recognised.
o Check your stars against the official sequence data in the database.
Home → Standing Data and Summaries → Sequence Data