Can't load TIF as DEM

[autoMick]

I thought this would be quick and easy... I just want to create a surface from a TIF file.

I right-click surfaces and hit "Create Surface from DEM..." and I just get the unhelpful error at the command line "Unable to read file".

If I create an empty surface and then try to add the DEM to its definition, I get "Invalid DEM file".

The .tif image seems fine - I can view it in photoshop, it says it is an 8 bit grey-scale image, 24,692 x 25,579 pixels. I can even MAPIINSERT it in Civil3d (see snip) and it comes to the correct coordinates (and shows the same pixel count etc. when inserting. The file is around 600MB. The associated files are shown below.

Without any decent error I not sure what I should try.

Any clues?

Thanks

- Mick

[Alfred.NESWADBA]

Hi,

>> I can view it in photoshop

If you can open it with Photoshop does not mean it's a DEM model.

If it tells you it's a 8bit-greyscale image this is even more a proof for it is NOT a DEM model. You can't use a color value (or greyscale values) to be used as DEM otherweise you would only have 256 different elevation values.

Can you give us a link to the file so we can download it and take a look into it?

- alfred -

[autoMick]

Well now I look at the image, it's obviously just a hill shaded render - the filename distracted me.

Nevertheless, I was able to load it into QGIS as a DEM - obviously the results were complete nonsense given the file contents, but it was interesting that it would accept the file, contour it, etc. whilst civil3d wouldn't have a bar of it.

I'll see if the correct file can be supplied to me

thanks

- Mick

[AllenJessup]

If QGIS opens it correctly. Try saving it in another compatible format.