[McIDAS #KGV-504968]: Changes in v2018 for L2 derived products

Hi Mike,

re:
> I was already aware that there would be some changes for L2 ABI derived
> products between v2017 and v2018.  For example, many products had a square
> root enhancement applied to them in v2017, but are linear in v2018.
> However, I have run into something that I did not expect, and I was hoping
> you could clarify something for me...

I certainly will IF I can...

re:
> I make my own color enhancement tables for the derived products, and even
> after taking into account them no longer being square root-ed things
> weren't lining up.

I had noticed the same thing when using some (but not all of the L2
enhancements that SSEC made available).  Perhaps those same enhancements
are being changed for the SSEC v2018.2 release that is coming up?

re:
> Using the Total Precipitable Water (TPW) product as an
> example, the values displayed were much too high compared to images made in
> v2017.  From SSEC's patch notes [1] I saw that one of the files changed was
> abincalb.inc, and this is where I noticed they were nearly all linear now
> too.

Yes, only 5 out of 27 are not LINEAR, and this is quite a bit different
from the v2017 distribution.  Interesting, I hadn't noticed this!

re:
> Looking a little harder at  abincalb.inc, I noticed the max value for TPW
> had changed from 100mm to 63.5mm.  When I compared that file to the v2017
> version, I see a number of other products had different values now.
> According to the documentation for the TPW product [2], the max value
> should still be 100mm.  After I took the new max value into account when
> making my own enhancement table, I saw values that matched both what made
> sense and what v2017 is making.  So why the change?

I have no idea.  What I can say is that I did not make the changes.  I'll
have to check the SSEC CVS repository to see what comments were made when
the new version of abincalb.inc was checked in.

re:
> Just for grins, I tried changing that value back to 100 and remade McIDAS
> to see if that would change things.  It didn't, though I admittedly rushed
> the remake/reinstall so I may have skipped a step.

That was what I would have done too, but a total rebuild should not have
been necessary.

re:
> I know this was a change made on SSEC's end so you may not know why they
> did it, but I wanted to mention it in case this was unintentional, or in
> the event this ends up helping someone else having a similar problem down
> the road.

I'll check the SSEC CVS code repository to see what comments were included
with the change(s).  I would be surprised if the changes were inadvertent 
given their testing routine, but one never knows...

Thanks for reporting the anomalies.  It may be that SSEC is testing using
the same L2 files that they had when they wrote the ABIN ADDE servers,
and, so are not using the ones coming across NOAAPort.  If I don't
understand the comments include in the CVS checkin, I'll make sure to
ask.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: KGV-504968
Department: Support McIDAS
Priority: Normal
Status: Open
===================
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