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I will receive TIFF files with the associated TFW. I always thought that these would open correctly in Arc. When I check the spatial reference on the TIFF it states undefined. So I try to add it myself, it doesn't take. I have a work around, I bring the TIFF into arc, right click and I can export with the correct projection(From dataframe) and it works.

I receive these TIFFs and TFWs from companies that use a lot of CAD software. Why would someone send TIFFs with no spatial reference and TFW files? I'm not saying you all would no that but why wouldn't the TFW work, because no spatial reference. The files come in via a zip drive is there some way that the spatial reference would be removed or if someone sends me a TIFF with the spatial reference via a zip it should stay?

I know my question is all over but I can't see all companies being wrong and sending a TIFF, with a TFW but the TIFF has no spatial reference and nothing opens. So I am thinking its more human error on my part.

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  • Are you saying that Define projection tool is not working on them? It only means they are sitting in protected folder. With or without world file is no worries as soon as it sits in the right place.
    – FelixIP
    Mar 23 '16 at 1:46
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A lot of software, such as photoshop, will strip the projection in the header. Usually you can just define the projection of the tiffs and that is all they need. You need to use the define projection(Data Management) in Arc, you can right click and batch them to do multiple tiffs at once.

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You encounter an issue in the way that CAD software and GIS software handle tif files.

GIS software produces Geotiff, which contains all necessary information to place the raster in the right spot. This includes CRS information, that is usually stored inside the Geotiff file.

The CAD software of your data provider only provides ordinary tif files with a world file . This file lets you calculate the coordinates of every pixel, but does not give any CRS information. The simple reason is that CAD software usually works within the same CRS for a project, while GIS software can reproject data with different CRS on-the-fly.

Furthermore, the world file can be added to any kind of raster format (jpg, png, tif), without the need to alter the raster file itself. CRS information can be stored externally in a .prj file. So it might help to create a .prj file (or copy and rename it from a shapefile in the same CRS).

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  • Ok that's what I thought. Most of the companies sending the tifs are using microstation/autocad. Is their any way that the company could send it differently to where it would save the correct info? As in a mappackage? I can add the projection myself but sometimes its a lot of tifs so I wanted to see if their is something that I can specify to alleviate the issue. thanks
    – pbdudley
    Mar 22 '16 at 17:13
  • Try the .prj file. You would not have to resave every tif, only duplicate the .prj file.
    – AndreJ
    Mar 22 '16 at 18:14

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