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Topic: Creation of the ANC file in the Spot sample that was available on this

How have to do to create the ANC for the sample that was available on this forum? I speak about the two spot images.
Many thanks and sorry for the stupid question!

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Re: Creation of the ANC file in the Spot sample that was available on this

You have to input the lead.dat file when asked in the ancillary data generation tool.

Sebastien

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Re: Creation of the ANC file in the Spot sample that was available on this

I create a shadedDem Image like you said me yesterday knowning the dem and the Anc file of first image. Then i obtained an image in grey scale but it's difficoult to find the tie points. I don't now why is it so hard to do? Could i do an error?

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Re: Creation of the ANC file in the Spot sample that was available on this

I use the function in ENVI (Topographic/create hill shade image) and in input i choose the sun elevation degree of 63.90000 and a sun azimuth of 137.4000 (returned from ANC file). I choose B/W linear and i obtain the image that it's difficoult to compare with the first image... sad

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Re: Creation of the ANC file in the Spot sample that was available on this

Is it all right what i'have done? Excuse me for the spam. Now i use the option of ENVI - WINDOW LINK DISPLAY to help meself in the search of tie points. Is it ok?

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Re: Creation of the ANC file in the Spot sample that was available on this

What you've done is good when you generate the tie point. However it's wrong to link the displays because the images don't have the same resolution and the SPOT raw image doesn't have any ground coordinates yet! Hence when you link the displayed, you're comparing images pixel-wise, which has no possible sense. You CANNOT link the display unless the images have geographic coordinates and are at the same resolution, which will only be the case when all the processing is finished.

Sebastien