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[McIDAS #UXQ-357287]: IMGREMAP colocation question

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  • Subject: [McIDAS #UXQ-357287]: IMGREMAP colocation question
  • Date: Thu, 31 Oct 2013 13:11:38 -0600
Hi Maryellen,

re:
> So I have an IMGREMAPped MSG region over Spain (img1=250x400) with RES=4KM
> and then a larger IMGREMAPped region that encompasses most of Europe and
> Africa, including Spain (img2=2500x3000) again with RES=4KM.When I try
> to colocate img1/Spain onto the larger MSG image/image2, it's not lining
> up 1 to 1 in lat/lon space, although it does line up in line/elem space.
> 
> When I use Alt-D and PC E to put the cursor on the MSG tile at the same
> spot it was on the SPNC tile I end up getting different lat/lon values. Is
> this because of how IMGREMAP does it's resolution degradation from 1km
> to 4km or is this because by nature the IMGREMAP args require a clat/lon
> so the pixel spacing in 4km might be slightly different since spnc and
> msg have different clat/clon values?
> 
> SPNC (250, 400) = (35:30:04, -3:41:54) => MSG(458, 1019) = (35:30:18, 
> -3:41:18)
> SPNC (  1,   1) = (44:27:46, 10:39:44) => MSG(209,  620) = (44:28:00, 
> 10:40:19)
> 
> I should point out the deltaLat/Lon between the two are less than a
> 4km pixel.  Am I doing something wrong or is this just by nature of
> IMGREMAP not possible?

I need some more information:

- What is the projection of the destination dataset element?

  I am thinking it would be RECT, but I want to know for sure

- Can you send me the IMGREMAP invocations you used to produce the two
  images?

  I would like to try and reproduce your findings so I can "see" what
  you are seeing.

re:
> THANK YOU!!!

No thanks are needed yet :-)

Cheers,

Tom
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Ticket Details
===================
Ticket ID: UXQ-357287
Department: Support McIDAS
Priority: Normal
Status: Open