[udf-dlm-develop] DLM news

[Harald F. <hf...@SS...>]

Hi all,

first I have to apologize if you will get this message twice, but I post it to 
the develop- as well as the release-group.

I have been fighting with the correct pointing determination for a couple of 
weeks now. One of the problems was related to the IDL-DLM interface.
Previous versions (before 1.41) returned everything as floating point numbers. 
For our pointing calculations we need the correct MET for periodic messages and 
our snapshot time. This MET is contained in the UDF file as a double precision 
number of milliseconds. The returned floating-point numbers were always 
inaccurate, so that our pointing differed to up to +-1.5 degrees.

So, whenever you are interested in a accuracy better than 1.5 degrees, I urge 
you to download the latest version of the DLM (1.42) and forget about everything 
older than this.

It may be that some of the nadir-jitter Bill Sandel showed during the last IMAGE 
meeting might have been caused by this inaccuracy as well.

Thank you again, Ed Santiago, for implementing this change into the DLM code.

Harald


=========================================================
Harald U. Frey 
Space Sciences Lab	   phone: 510-643-3323
University of California   fax:   510-643-2624      
Berkeley, CA 94720-7450    email: hf...@ss...